Clean up codebase

- change indent to 2 spaces
- refactor

21 files changed, 2087 insertions, 1885 deletions

diff --git a/gfbgraph/gfbgraph-album.c b/gfbgraph/gfbgraph-album.c
index 5ae726d..8f8cec4 100644
--- a/gfbgraph/gfbgraph-album.c
+++ b/gfbgraph/gfbgraph-album.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -35,209 +36,206 @@
 #include "gfbgraph-connectable.h"
 
 enum {
-        PROP_O,
-
-        PROP_NAME,
-        PROP_DESCRIPTION,
-        PROP_COVER_PHOTO,
-        PROP_COUNT
+  PROP_O,
+  PROP_NAME,
+  PROP_DESCRIPTION,
+  PROP_COVER_PHOTO,
+  PROP_COUNT
 };
 
 struct _GFBGraphAlbumPrivate {
-        gchar *name;
-        gchar *description;
-        gchar *cover_photo;
-        guint  count;
+  gchar *name;
+  gchar *description;
+  gchar *cover_photo;
+  guint  count;
 };
 
-static void gfbgraph_album_init         (GFBGraphAlbum *obj);
-static void gfbgraph_album_class_init   (GFBGraphAlbumClass *klass);
-static void gfbgraph_album_finalize     (GObject *obj);
-static void gfbgraph_album_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
-static void gfbgraph_album_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
-
-static void gfbgraph_album_connectable_iface_init (GFBGraphConnectableInterface *iface);
-GHashTable* gfbgraph_album_get_connection_post_params (GFBGraphConnectable *self, GType node_type);
-
-#define GFBGRAPH_ALBUM_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_ALBUM, GFBGraphAlbumPrivate))
+#define GFBGRAPH_ALBUM_GET_PRIVATE(o) \
+  (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_ALBUM, GFBGraphAlbumPrivate))
 
 static GFBGraphNodeClass *parent_class = NULL;
 
+static void connectable_iface_init (GFBGraphConnectableInterface *iface);
+
 G_DEFINE_TYPE_WITH_CODE (GFBGraphAlbum, gfbgraph_album, GFBGRAPH_TYPE_NODE,
-                         G_IMPLEMENT_INTERFACE (GFBGRAPH_TYPE_CONNECTABLE, gfbgraph_album_connectable_iface_init));
+  G_IMPLEMENT_INTERFACE (GFBGRAPH_TYPE_CONNECTABLE, connectable_iface_init));
 
 static void
-gfbgraph_album_init (GFBGraphAlbum *obj)
+gfbgraph_album_finalize (GObject *obj)
 {
-        obj->priv = GFBGRAPH_ALBUM_GET_PRIVATE(obj);
+  GFBGraphAlbumPrivate *priv = GFBGRAPH_ALBUM_GET_PRIVATE (obj);
+
+  if (priv->name)
+    g_free (priv->name);
+  if (priv->description)
+    g_free (priv->description);
+  if (priv->cover_photo)
+    g_free (priv->cover_photo);
+
+  G_OBJECT_CLASS(parent_class)->finalize (obj);
 }
 
 static void
-gfbgraph_album_class_init (GFBGraphAlbumClass *klass)
+gfbgraph_album_set_property (GObject      *object,
+                             guint         prop_id,
+                             const GValue *value,
+                             GParamSpec   *pspec)
 {
-        GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
-
-        parent_class            = g_type_class_peek_parent (klass);
-
-        gobject_class->finalize = gfbgraph_album_finalize;
-        gobject_class->set_property = gfbgraph_album_set_property;
-        gobject_class->get_property = gfbgraph_album_get_property;
-
-        g_type_class_add_private (gobject_class, sizeof(GFBGraphAlbumPrivate));
-
-        /**
-         * GFBGraphAlbum:name:
-         *
-         * The album name.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_NAME,
-                                         g_param_spec_string ("name",
-                                                              "The title", "The name of the album",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphAlbum:description:
-         *
-         * The album description given by the owner.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_DESCRIPTION,
-                                         g_param_spec_string ("description",
-                                                              "The description", "The description of the album",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphAlbum:cover_photo:
-         *
-         * The node ID for the album cover photo. It's an ID for a #GFBGraphPhoto node.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_COVER_PHOTO,
-                                         g_param_spec_string ("cover_photo",
-                                                              "Cover photo", "The ID for the cover photo of the album",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphAlbum:count:
-         *
-         * The number of photos in the album.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_COUNT,
-                                         g_param_spec_uint ("count",
-                                                           "Number of photos", "The number of photos in the album",
-                                                           0, G_MAXUINT, 0,
-                                                           G_PARAM_READABLE | G_PARAM_WRITABLE));
-
+  GFBGraphAlbumPrivate *priv = GFBGRAPH_ALBUM_GET_PRIVATE (object);
+
+  switch (prop_id) {
+    case PROP_NAME:
+      if (priv->name)
+        g_free (priv->name);
+      priv->name = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_DESCRIPTION:
+      if (priv->description)
+        g_free (priv->description);
+      priv->description = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_COVER_PHOTO:
+      if (priv->cover_photo)
+        g_free (priv->cover_photo);
+      priv->cover_photo = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_COUNT:
+      priv->count = g_value_get_uint (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_album_finalize (GObject *obj)
+gfbgraph_album_get_property (GObject    *object,
+                             guint       prop_id,
+                             GValue     *value,
+                             GParamSpec *pspec)
 {
-        GFBGraphAlbumPrivate *priv;
-
-        priv = GFBGRAPH_ALBUM_GET_PRIVATE (obj);
-
-        if (priv->name)
-                g_free (priv->name);
-        if (priv->description)
-                g_free (priv->description);
-        if (priv->cover_photo)
-                g_free (priv->cover_photo);
-
-        G_OBJECT_CLASS(parent_class)->finalize (obj);
+  GFBGraphAlbumPrivate *priv = GFBGRAPH_ALBUM_GET_PRIVATE (object);
+
+  switch (prop_id) {
+    case PROP_NAME:
+      g_value_set_string (value, priv->name);
+      break;
+    case PROP_DESCRIPTION:
+      g_value_set_string (value, priv->description);
+      break;
+    case PROP_COVER_PHOTO:
+      g_value_set_string (value, priv->cover_photo);
+      break;
+    case PROP_COUNT:
+      g_value_set_uint (value, priv->count);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_album_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+gfbgraph_album_class_init (GFBGraphAlbumClass *klass)
 {
-        GFBGraphAlbumPrivate *priv;
-
-        priv = GFBGRAPH_ALBUM_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_NAME:
-                        if (priv->name)
-                                g_free (priv->name);
-                        priv->name = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_DESCRIPTION:
-                        if (priv->description)
-                                g_free (priv->description);
-                        priv->description = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_COVER_PHOTO:
-                        if (priv->cover_photo)
-                                g_free (priv->cover_photo);
-                        priv->cover_photo = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_COUNT:
-                        priv->count = g_value_get_uint (value);
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  parent_class            = g_type_class_peek_parent (klass);
+
+  gobject_class->finalize = gfbgraph_album_finalize;
+  gobject_class->set_property = gfbgraph_album_set_property;
+  gobject_class->get_property = gfbgraph_album_get_property;
+
+  g_type_class_add_private (gobject_class, sizeof(GFBGraphAlbumPrivate));
+
+  /**
+   * GFBGraphAlbum:name:
+   *
+   * The album name.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_NAME,
+                                   g_param_spec_string ("name",
+                                                        "The title",
+                                                        "The name of the album",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphAlbum:description:
+   *
+   * The album description given by the owner.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_DESCRIPTION,
+                                   g_param_spec_string ("description",
+                                                        "The description",
+                                                        "The description of the album",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphAlbum:cover_photo:
+   *
+   * The node ID for the album cover photo. It's an ID for a #GFBGraphPhoto node.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_COVER_PHOTO,
+                                   g_param_spec_string ("cover_photo",
+                                                        "Cover photo",
+                                                        "The ID for the cover photo of the album",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphAlbum:count:
+   *
+   * The number of photos in the album.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_COUNT,
+                                   g_param_spec_uint ("count",
+                                                      "Number of photos",
+                                                      "The number of photos in the album",
+                                                      0, G_MAXUINT, 0,
+                                                      G_PARAM_READABLE | G_PARAM_WRITABLE));
+
 }
 
 static void
-gfbgraph_album_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+gfbgraph_album_init (GFBGraphAlbum *obj)
 {
-        GFBGraphAlbumPrivate *priv;
-
-        priv = GFBGRAPH_ALBUM_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_NAME:
-                        g_value_set_string (value, priv->name);
-                        break;
-                case PROP_DESCRIPTION:
-                        g_value_set_string (value, priv->description);
-                        break;
-                case PROP_COVER_PHOTO:
-                        g_value_set_string (value, priv->cover_photo);
-                        break;
-                case PROP_COUNT:
-                        g_value_set_uint (value, priv->count);
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  obj->priv = GFBGRAPH_ALBUM_GET_PRIVATE(obj);
 }
 
-static void
-gfbgraph_album_connectable_iface_init (GFBGraphConnectableInterface *iface)
+static GHashTable *
+get_connection_post_params (GFBGraphConnectable *self,
+                            GType                node_type)
 {
-        GHashTable *connections;
+  GHashTable *params;
+  GFBGraphAlbumPrivate *priv = GFBGRAPH_ALBUM_GET_PRIVATE (self);
 
-        connections = g_hash_table_new (g_str_hash, g_str_equal);
-        g_hash_table_insert (connections, (gpointer) g_type_name (GFBGRAPH_TYPE_USER), (gpointer) "albums");
+  params = g_hash_table_new (g_str_hash, g_str_equal);
+  g_hash_table_insert (params, "name", priv->name);
+  if (priv->description != NULL)
+    g_hash_table_insert (params, "message", priv->description);
+  /* TODO: Incorpate the "privacy" param */
 
-        iface->connections = connections;
-        iface->get_connection_post_params = gfbgraph_album_get_connection_post_params;
-        iface->parse_connected_data = gfbgraph_connectable_default_parse_connected_data;
+  return params;
 }
 
-GHashTable*
-gfbgraph_album_get_connection_post_params (GFBGraphConnectable *self, GType node_type)
+static void
+connectable_iface_init (GFBGraphConnectableInterface *iface)
 {
-        GHashTable *params;
-        GFBGraphAlbumPrivate *priv;
-
-        priv = GFBGRAPH_ALBUM_GET_PRIVATE (self);
+  GHashTable *connections = g_hash_table_new (g_str_hash, g_str_equal);
 
-        params = g_hash_table_new (g_str_hash, g_str_equal);
-        g_hash_table_insert (params, "name", priv->name);
-        if (priv->description != NULL)
-                g_hash_table_insert (params, "message", priv->description);
-        /* TODO: Incorpate the "privacy" param */
+  g_hash_table_insert (connections,
+                       (gpointer) g_type_name (GFBGRAPH_TYPE_USER),
+                       (gpointer) "albums");
 
-        return params;
+  iface->connections = connections;
+  iface->get_connection_post_params = get_connection_post_params;
+  iface->parse_connected_data = gfbgraph_connectable_default_parse_connected_data;
 }
 
 /**
@@ -247,10 +245,10 @@ gfbgraph_album_get_connection_post_params (GFBGraphConnectable *self, GType node
  *
  * Returns: (transfer full): a new #GFBGraphAlbum; unref with g_object_unref()
  **/
-GFBGraphAlbum*
+GFBGraphAlbum *
 gfbgraph_album_new (void)
 {
-        return GFBGRAPH_ALBUM (g_object_new(GFBGRAPH_TYPE_ALBUM, NULL));
+  return GFBGRAPH_ALBUM (g_object_new (GFBGRAPH_TYPE_ALBUM, NULL));
 }
 
 /**
@@ -263,10 +261,15 @@ gfbgraph_album_new (void)
  *
  * Returns: (transfer full): a new #GFBGraphAlbum; unref with g_object_unref()
  **/
-GFBGraphAlbum*
-gfbgraph_album_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GError **error)
+GFBGraphAlbum *
+gfbgraph_album_new_from_id (GFBGraphAuthorizer  *authorizer,
+                            const gchar         *id,
+                            GError             **error)
 {
-        return GFBGRAPH_ALBUM (gfbgraph_node_new_from_id (authorizer, id, GFBGRAPH_TYPE_ALBUM, error));
+  return GFBGRAPH_ALBUM (gfbgraph_node_new_from_id (authorizer,
+                                                    id,
+                                                    GFBGRAPH_TYPE_ALBUM,
+                                                    error));
 }
 
 /**
@@ -275,12 +278,12 @@ gfbgraph_album_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GEr
  *
  * Returns: (transfer none): the @album name, or %NULL.
  **/
-const gchar*
+const gchar *
 gfbgraph_album_get_name (GFBGraphAlbum *album)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_ALBUM (album), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_ALBUM (album), NULL);
 
-        return album->priv->name;
+  return album->priv->name;
 }
 
 /**
@@ -289,12 +292,12 @@ gfbgraph_album_get_name (GFBGraphAlbum *album)
  *
  * Returns: (transfer none): the @album description, or %NULL.
  **/
-const gchar*
+const gchar *
 gfbgraph_album_get_description (GFBGraphAlbum *album)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_ALBUM (album), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_ALBUM (album), NULL);
 
-        return album->priv->description;
+  return album->priv->description;
 }
 
 /**
@@ -303,12 +306,12 @@ gfbgraph_album_get_description (GFBGraphAlbum *album)
  *
  * Returns: (transfer none): the cover photo node ID or %NULL.
  **/
-const gchar*
+const gchar *
 gfbgraph_album_get_cover_photo_id (GFBGraphAlbum *album)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_ALBUM (album), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_ALBUM (album), NULL);
 
-        return album->priv->cover_photo;
+  return album->priv->cover_photo;
 }
 
 /**
@@ -320,9 +323,9 @@ gfbgraph_album_get_cover_photo_id (GFBGraphAlbum *album)
 guint
 gfbgraph_album_get_count (GFBGraphAlbum *album)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_ALBUM (album), -1);
+  g_return_val_if_fail (GFBGRAPH_IS_ALBUM (album), -1);
 
-        return album->priv->count;
+  return album->priv->count;
 }
 
 /**
@@ -333,14 +336,15 @@ gfbgraph_album_get_count (GFBGraphAlbum *album)
  * Sets the name for the @album.
  **/
 void
-gfbgraph_album_set_name (GFBGraphAlbum *album, const gchar *name)
+gfbgraph_album_set_name (GFBGraphAlbum *album,
+                         const gchar   *name)
 {
-        g_return_if_fail (GFBGRAPH_IS_ALBUM (album));
-        g_return_if_fail (name != NULL);
+  g_return_if_fail (GFBGRAPH_IS_ALBUM (album));
+  g_return_if_fail (name != NULL);
 
-        g_object_set (G_OBJECT (album),
-                      "name", name,
-                      NULL);
+  g_object_set (G_OBJECT (album),
+                "name", name,
+                NULL);
 }
 
 /**
@@ -351,12 +355,13 @@ gfbgraph_album_set_name (GFBGraphAlbum *album, const gchar *name)
  * Sets the description for the @album.
  **/
 void
-gfbgraph_album_set_description (GFBGraphAlbum *album, const gchar *description)
+gfbgraph_album_set_description (GFBGraphAlbum *album,
+                                const gchar   *description)
 {
-        g_return_if_fail (GFBGRAPH_IS_ALBUM (album));
-        g_return_if_fail (description != NULL);
+  g_return_if_fail (GFBGRAPH_IS_ALBUM (album));
+  g_return_if_fail (description != NULL);
 
-        g_object_set (G_OBJECT (album),
-                      "description", description,
-                      NULL);
+  g_object_set (G_OBJECT (album),
+                "description", description,
+                NULL);
 }
diff --git a/gfbgraph/gfbgraph-album.h b/gfbgraph/gfbgraph-album.h
index e0528fb..b752e5b 100644
--- a/gfbgraph/gfbgraph-album.h
+++ b/gfbgraph/gfbgraph-album.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -25,12 +26,17 @@
 
 G_BEGIN_DECLS
 
-#define GFBGRAPH_TYPE_ALBUM             (gfbgraph_album_get_type())
-#define GFBGRAPH_ALBUM(obj)             (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_ALBUM,GFBGraphAlbum))
-#define GFBGRAPH_ALBUM_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_ALBUM,GFBGraphAlbumClass))
-#define GFBGRAPH_IS_ALBUM(obj)          (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_ALBUM))
-#define GFBGRAPH_IS_ALBUM_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_ALBUM))
-#define GFBGRAPH_ALBUM_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_ALBUM,GFBGraphAlbumClass))
+#define GFBGRAPH_TYPE_ALBUM  (gfbgraph_album_get_type())
+#define GFBGRAPH_ALBUM(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj), GFBGRAPH_TYPE_ALBUM,GFBGraphAlbum))
+#define GFBGRAPH_ALBUM_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass), GFBGRAPH_TYPE_ALBUM,GFBGraphAlbumClass))
+#define GFBGRAPH_IS_ALBUM(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj), GFBGRAPH_TYPE_ALBUM))
+#define GFBGRAPH_IS_ALBUM_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass), GFBGRAPH_TYPE_ALBUM))
+#define GFBGRAPH_ALBUM_GET_CLASS(obj) \
+  (G_TYPE_INSTANCE_GET_CLASS((obj), GFBGRAPH_TYPE_ALBUM,GFBGraphAlbumClass))
 
 typedef struct _GFBGraphAlbum        GFBGraphAlbum;
 typedef struct _GFBGraphAlbumClass   GFBGraphAlbumClass;
@@ -39,27 +45,31 @@ typedef struct _GFBGraphAlbumPrivate GFBGraphAlbumPrivate;
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (GFBGraphAlbum, g_object_unref)
 
 struct _GFBGraphAlbum {
-        GFBGraphNode parent;
+  GFBGraphNode parent;
 
-        /*< private >*/
-        GFBGraphAlbumPrivate *priv;
+    /*< private >*/
+  GFBGraphAlbumPrivate *priv;
 };
 
 struct _GFBGraphAlbumClass {
-        GFBGraphNodeClass parent_class;
+  GFBGraphNodeClass parent_class;
 };
 
 GType          gfbgraph_album_get_type    (void) G_GNUC_CONST;
 GFBGraphAlbum* gfbgraph_album_new         (void);
-GFBGraphAlbum* gfbgraph_album_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GError **error);
+GFBGraphAlbum* gfbgraph_album_new_from_id (GFBGraphAuthorizer  *authorizer,
+                                           const gchar         *id,
+                                           GError             **error);
 
 const gchar*   gfbgraph_album_get_name           (GFBGraphAlbum *album);
 const gchar*   gfbgraph_album_get_description    (GFBGraphAlbum *album);
 const gchar*   gfbgraph_album_get_cover_photo_id (GFBGraphAlbum *album);
 guint          gfbgraph_album_get_count          (GFBGraphAlbum *album);
 
-void           gfbgraph_album_set_name           (GFBGraphAlbum *album, const gchar *name);
-void           gfbgraph_album_set_description    (GFBGraphAlbum *album, const gchar *description);
+void           gfbgraph_album_set_name           (GFBGraphAlbum *album,
+                                                  const gchar   *name);
+void           gfbgraph_album_set_description    (GFBGraphAlbum *album,
+                                                  const gchar   *description);
 
 G_END_DECLS
 
diff --git a/gfbgraph/gfbgraph-authorizer.c b/gfbgraph/gfbgraph-authorizer.c
index 95cf06e..2ce2341 100644
--- a/gfbgraph/gfbgraph-authorizer.c
+++ b/gfbgraph/gfbgraph-authorizer.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -46,10 +47,12 @@ gfbgraph_authorizer_default_init (GFBGraphAuthorizerInterface *iface)
  * This method modifies @call in place and is thread safe.
  */
 void
-gfbgraph_authorizer_process_call (GFBGraphAuthorizer *iface, RestProxyCall *call)
+gfbgraph_authorizer_process_call (GFBGraphAuthorizer *iface,
+                                  RestProxyCall      *call)
 {
-        g_return_if_fail (GFBGRAPH_IS_AUTHORIZER (iface));
-        GFBGRAPH_AUTHORIZER_GET_IFACE (iface)->process_call (iface, call);
+  g_return_if_fail (GFBGRAPH_IS_AUTHORIZER (iface));
+
+  GFBGRAPH_AUTHORIZER_GET_IFACE (iface)->process_call (iface, call);
 }
 
 /**
@@ -63,10 +66,12 @@ gfbgraph_authorizer_process_call (GFBGraphAuthorizer *iface, RestProxyCall *call
  * This method modifies @message in place and is thread safe.
  */
 void
-gfbgraph_authorizer_process_message (GFBGraphAuthorizer *iface, SoupMessage *message)
+gfbgraph_authorizer_process_message (GFBGraphAuthorizer *iface,
+                                     SoupMessage        *message)
 {
-        g_return_if_fail (GFBGRAPH_IS_AUTHORIZER (iface));
-        GFBGRAPH_AUTHORIZER_GET_IFACE (iface)->process_message (iface, message);
+  g_return_if_fail (GFBGRAPH_IS_AUTHORIZER (iface));
+
+  GFBGRAPH_AUTHORIZER_GET_IFACE (iface)->process_message (iface, message);
 }
 
 /**
@@ -83,8 +88,13 @@ gfbgraph_authorizer_process_message (GFBGraphAuthorizer *iface, SoupMessage *mes
  * Returns: %TRUE if the authorizer now has a valid token.
  */
 gboolean
-gfbgraph_authorizer_refresh_authorization (GFBGraphAuthorizer *iface, GCancellable *cancellable, GError **error)
+gfbgraph_authorizer_refresh_authorization (GFBGraphAuthorizer  *iface,
+                                           GCancellable        *cancellable,
+                                           GError             **error)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (iface), FALSE);
-        return GFBGRAPH_AUTHORIZER_GET_IFACE (iface)->refresh_authorization (iface, cancellable, error);
+  g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (iface), FALSE);
+
+  return GFBGRAPH_AUTHORIZER_GET_IFACE (iface)->refresh_authorization (iface,
+                                                                       cancellable,
+                                                                       error);
 }
diff --git a/gfbgraph/gfbgraph-authorizer.h b/gfbgraph/gfbgraph-authorizer.h
index 6100cbd..bc57d76 100644
--- a/gfbgraph/gfbgraph-authorizer.h
+++ b/gfbgraph/gfbgraph-authorizer.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -27,10 +28,13 @@
 
 G_BEGIN_DECLS
 
-#define GFBGRAPH_TYPE_AUTHORIZER          (gfbgraph_authorizer_get_type ())
-#define GFBGRAPH_AUTHORIZER(o)            (G_TYPE_CHECK_INSTANCE_CAST ((o), GFBGRAPH_TYPE_AUTHORIZER, GFBGraphAuthorizer))
-#define GFBGRAPH_IS_AUTHORIZER(o)         (G_TYPE_CHECK_INSTANCE_TYPE ((o), GFBGRAPH_TYPE_AUTHORIZER))
-#define GFBGRAPH_AUTHORIZER_GET_IFACE(o)  (G_TYPE_INSTANCE_GET_INTERFACE ((o), GFBGRAPH_TYPE_AUTHORIZER, GFBGraphAuthorizerInterface))
+#define GFBGRAPH_TYPE_AUTHORIZER (gfbgraph_authorizer_get_type ())
+#define GFBGRAPH_AUTHORIZER(o) \
+  (G_TYPE_CHECK_INSTANCE_CAST ((o), GFBGRAPH_TYPE_AUTHORIZER, GFBGraphAuthorizer))
+#define GFBGRAPH_IS_AUTHORIZER(o) \
+  (G_TYPE_CHECK_INSTANCE_TYPE ((o), GFBGRAPH_TYPE_AUTHORIZER))
+#define GFBGRAPH_AUTHORIZER_GET_IFACE(o) \
+  (G_TYPE_INSTANCE_GET_INTERFACE ((o), GFBGRAPH_TYPE_AUTHORIZER, GFBGraphAuthorizerInterface))
 
 typedef struct _GFBGraphAuthorizer          GFBGraphAuthorizer;
 typedef struct _GFBGraphAuthorizerInterface GFBGraphAuthorizerInterface;
@@ -46,26 +50,26 @@ typedef struct _GFBGraphAuthorizerInterface GFBGraphAuthorizerInterface;
  * Interface structure for #GFBGraphAuthorizer. All methos should be thread safe.
  **/
 struct _GFBGraphAuthorizerInterface {
-        GTypeInterface parent;
+  GTypeInterface parent;
 
-        void        (*process_call)          (GFBGraphAuthorizer *iface,
-                                              RestProxyCall *call);
-        void        (*process_message)       (GFBGraphAuthorizer *iface,
-                                              SoupMessage *message);
-        gboolean    (*refresh_authorization) (GFBGraphAuthorizer *iface,
-                                              GCancellable *cancellable,
-                                              GError **error);
+  void      (*process_call)           (GFBGraphAuthorizer *iface,
+                                       RestProxyCall      *call);
+  void      (*process_message)        (GFBGraphAuthorizer *iface,
+                                       SoupMessage        *message);
+  gboolean  (*refresh_authorization)  (GFBGraphAuthorizer  *iface,
+                                       GCancellable        *cancellable,
+                                       GError             **error);
 };
 
 GType    gfbgraph_authorizer_get_type              (void) G_GNUC_CONST;
 
 void     gfbgraph_authorizer_process_call          (GFBGraphAuthorizer *iface,
-                                                    RestProxyCall *call);
+                                                    RestProxyCall      *call);
 void     gfbgraph_authorizer_process_message       (GFBGraphAuthorizer *iface,
-                                                    SoupMessage *message);
-gboolean gfbgraph_authorizer_refresh_authorization (GFBGraphAuthorizer *iface,
-                                                    GCancellable *cancellable,
-                                                    GError **error);
+                                                    SoupMessage        *message);
+gboolean gfbgraph_authorizer_refresh_authorization (GFBGraphAuthorizer  *iface,
+                                                    GCancellable        *cancellable,
+                                                    GError             **error);
 
 G_END_DECLS
 
diff --git a/gfbgraph/gfbgraph-common.c b/gfbgraph/gfbgraph-common.c
index 137f880..c60e635 100644
--- a/gfbgraph/gfbgraph-common.c
+++ b/gfbgraph/gfbgraph-common.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013-2015 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -32,20 +33,20 @@
  *
  * Returns: (transfer full): a new #RestProxyCall or %NULL in case of error.
  **/
-RestProxyCall*
+RestProxyCall *
 gfbgraph_new_rest_call (GFBGraphAuthorizer *authorizer)
 {
-        RestProxy *proxy;
-        RestProxyCall *rest_call;
+  RestProxy *proxy;
+  RestProxyCall *rest_call;
 
-        g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
 
-        proxy = rest_proxy_new (FACEBOOK_ENDPOINT, FALSE);
-        rest_call = rest_proxy_new_call (proxy);
+  proxy = rest_proxy_new (FACEBOOK_ENDPOINT, FALSE);
+  rest_call = rest_proxy_new_call (proxy);
 
-        gfbgraph_authorizer_process_call (authorizer, rest_call);
+  gfbgraph_authorizer_process_call (authorizer, rest_call);
 
-        g_object_unref (proxy);
+  g_object_unref (proxy);
 
-        return rest_call;
+  return rest_call;
 }
diff --git a/gfbgraph/gfbgraph-common.h b/gfbgraph/gfbgraph-common.h
index b2bad18..4af3e85 100644
--- a/gfbgraph/gfbgraph-common.h
+++ b/gfbgraph/gfbgraph-common.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
diff --git a/gfbgraph/gfbgraph-connectable.c b/gfbgraph/gfbgraph-connectable.c
index 82b0765..b24be50 100644
--- a/gfbgraph/gfbgraph-connectable.c
+++ b/gfbgraph/gfbgraph-connectable.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -39,27 +40,27 @@ G_DEFINE_INTERFACE (GFBGraphConnectable, gfbgraph_connectable, GFBGRAPH_TYPE_NOD
 static void
 gfbgraph_connectable_default_init (GFBGraphConnectableInterface *iface)
 {
-        iface->connections = NULL;
+  iface->connections = NULL;
 
-        iface->get_connection_post_params = NULL;
-        iface->parse_connected_data = NULL;
+  iface->get_connection_post_params = NULL;
+  iface->parse_connected_data = NULL;
 }
 
-static GHashTable*
+static GHashTable *
 get_connections (GFBGraphConnectableInterface *iface)
 {
-        /* The GHashTable contains the connections for a node.
-         * The key must be the g_type_name() of a GFBGRAPH_TYPE_NODE, and the value
-         * must be the function name to call in order to retrieve the nodes connected
-         * to the GFBGraphNode indicated by GFBGRAPH_TYPE_NODE.
-         */
-        GHashTable *connections;
-
-        connections = iface->connections;
-        /* If no connections... Why you implement this iface? */
-        g_assert (g_hash_table_size (connections) > 0);
-
-        return connections;
+  /* The GHashTable contains the connections for a node.
+   * The key must be the g_type_name() of a GFBGRAPH_TYPE_NODE, and the value
+   * must be the function name to call in order to retrieve the nodes connected
+   * to the GFBGraphNode indicated by GFBGRAPH_TYPE_NODE.
+   */
+  GHashTable *connections;
+
+  connections = iface->connections;
+  /* If no connections... Why you implement this iface? */
+  g_assert (g_hash_table_size (connections) > 0);
+
+  return connections;
 }
 
 /**
@@ -72,19 +73,20 @@ get_connections (GFBGraphConnectableInterface *iface)
  *
  * Returns: (transfer full): A string based #GHashTable with the params and his values or %NULL.
  **/
-GHashTable*
-gfbgraph_connectable_get_connection_post_params (GFBGraphConnectable *self, GType node_type)
+GHashTable *
+gfbgraph_connectable_get_connection_post_params (GFBGraphConnectable *self,
+                                                 GType                node_type)
 {
-        GFBGraphConnectableInterface *iface;
+  GFBGraphConnectableInterface *iface;
 
-        g_return_val_if_fail (GFBGRAPH_IS_CONNECTABLE (self), NULL);
-        g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), NULL);
-        g_return_val_if_fail (gfbgraph_connectable_is_connectable_to (self, node_type), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_CONNECTABLE (self), NULL);
+  g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), NULL);
+  g_return_val_if_fail (gfbgraph_connectable_is_connectable_to (self, node_type), NULL);
 
-        iface = GFBGRAPH_CONNECTABLE_GET_IFACE (self);
-        g_assert (iface->get_connection_post_params != NULL);
+  iface = GFBGRAPH_CONNECTABLE_GET_IFACE (self);
+  g_assert (iface->get_connection_post_params != NULL);
 
-        return iface->get_connection_post_params (self, node_type);
+  return iface->get_connection_post_params (self, node_type);
 }
 
 /**
@@ -98,17 +100,19 @@ gfbgraph_connectable_get_connection_post_params (GFBGraphConnectable *self, GTyp
  *
  * Returns: (element-type GFBGraphNode) (transfer full): a newly-allocated #GList of #GFBGraphNode created from the @payload or %NULL.
  **/
-GList*
-gfbgraph_connectable_parse_connected_data (GFBGraphConnectable *self, const gchar *payload, GError **error)
+GList *
+gfbgraph_connectable_parse_connected_data (GFBGraphConnectable  *self,
+                                           const gchar          *payload,
+                                           GError              **error)
 {
-        GFBGraphConnectableInterface *iface;
+  GFBGraphConnectableInterface *iface;
 
-        g_return_val_if_fail (GFBGRAPH_IS_CONNECTABLE (self), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_CONNECTABLE (self), NULL);
 
-        iface = GFBGRAPH_CONNECTABLE_GET_IFACE (self);
-        g_assert (iface->parse_connected_data != NULL);
+  iface = GFBGRAPH_CONNECTABLE_GET_IFACE (self);
+  g_assert (iface->parse_connected_data != NULL);
 
-        return iface->parse_connected_data (self, payload, error);
+  return iface->parse_connected_data (self, payload, error);
 }
 
 
@@ -124,18 +128,19 @@ gfbgraph_connectable_parse_connected_data (GFBGraphConnectable *self, const gcha
  * %FALSE otherwise.
  **/
 gboolean
-gfbgraph_connectable_is_connectable_to (GFBGraphConnectable *self, GType node_type)
+gfbgraph_connectable_is_connectable_to (GFBGraphConnectable *self,
+                                        GType                node_type)
 {
-        GFBGraphConnectableInterface *iface;
-        GHashTable *connections;
+  GFBGraphConnectableInterface *iface;
+  GHashTable *connections;
 
-        g_return_val_if_fail (GFBGRAPH_IS_CONNECTABLE (self), FALSE);
-        g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), FALSE);
+  g_return_val_if_fail (GFBGRAPH_IS_CONNECTABLE (self), FALSE);
+  g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), FALSE);
 
-        iface = GFBGRAPH_CONNECTABLE_GET_IFACE (self);
+  iface = GFBGRAPH_CONNECTABLE_GET_IFACE (self);
+  connections = get_connections (iface);
 
-        connections = get_connections (iface);
-        return g_hash_table_contains (connections, g_type_name (node_type));
+  return g_hash_table_contains (connections, g_type_name (node_type));
 }
 
 /**
@@ -148,20 +153,21 @@ gfbgraph_connectable_is_connectable_to (GFBGraphConnectable *self, GType node_ty
  *
  * Returns: (transfer none): a const #gchar with the function path or %NULL.
  **/
-const gchar*
-gfbgraph_connectable_get_connection_path (GFBGraphConnectable *self, GType node_type)
+const gchar *
+gfbgraph_connectable_get_connection_path (GFBGraphConnectable *self,
+                                          GType                node_type)
 {
-        GFBGraphConnectableInterface *iface;
-        GHashTable *connections;
+  GFBGraphConnectableInterface *iface;
+  GHashTable *connections;
 
-        g_return_val_if_fail (GFBGRAPH_IS_CONNECTABLE (self), NULL);
-        g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), NULL);
-        g_return_val_if_fail (gfbgraph_connectable_is_connectable_to (self, node_type), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_CONNECTABLE (self), NULL);
+  g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), NULL);
+  g_return_val_if_fail (gfbgraph_connectable_is_connectable_to (self, node_type), NULL);
 
-        iface = GFBGRAPH_CONNECTABLE_GET_IFACE (self);
+  iface = GFBGRAPH_CONNECTABLE_GET_IFACE (self);
+  connections = get_connections (iface);
 
-        connections = get_connections (iface);
-        return (const gchar *) g_hash_table_lookup (connections, g_type_name (node_type));
+  return (const gchar *) g_hash_table_lookup (connections, g_type_name (node_type));
 }
 
 /**
@@ -179,36 +185,38 @@ gfbgraph_connectable_get_connection_path (GFBGraphConnectable *self, GType node_
  *
  * Returns: (element-type GFBGraphNode) (transfer full): a newly-allocated #GList of #GFBGraphNode with the same #GType as @self.
  **/
-GList*
-gfbgraph_connectable_default_parse_connected_data (GFBGraphConnectable *self, const gchar *payload, GError **error)
+GList *
+gfbgraph_connectable_default_parse_connected_data (GFBGraphConnectable  *self,
+                                                   const gchar          *payload,
+                                                   GError              **error)
 {
-        GList *nodes_list = NULL;
-        JsonParser *jparser;
-        GType node_type;
-
-        node_type = G_OBJECT_TYPE (self);
-
-        jparser = json_parser_new ();
-        if (json_parser_load_from_data (jparser, payload, -1, error)) {
-                JsonNode *root_jnode;
-                JsonObject *main_jobject;
-                JsonArray *nodes_jarray;
-                int i = 0;
-
-                root_jnode = json_parser_get_root (jparser);
-                main_jobject = json_node_get_object (root_jnode);
-                nodes_jarray = json_object_get_array_member (main_jobject, "data");
-                for (i = 0; i < json_array_get_length (nodes_jarray); i++) {
-                        JsonNode *jnode;
-                        GFBGraphNode *node;
-
-                        jnode = json_array_get_element (nodes_jarray, i);
-                        node = GFBGRAPH_NODE (json_gobject_deserialize (node_type, jnode));
-                        nodes_list = g_list_append (nodes_list, node);
-                }
-        }
-
-        g_clear_object (&jparser);
-
-        return nodes_list;
+  GList *nodes_list = NULL;
+  JsonParser *jparser;
+  GType node_type;
+
+  node_type = G_OBJECT_TYPE (self);
+
+  jparser = json_parser_new ();
+  if (json_parser_load_from_data (jparser, payload, -1, error)) {
+    JsonNode *root_jnode;
+    JsonObject *main_jobject;
+    JsonArray *nodes_jarray;
+    int i = 0;
+
+    root_jnode = json_parser_get_root (jparser);
+    main_jobject = json_node_get_object (root_jnode);
+    nodes_jarray = json_object_get_array_member (main_jobject, "data");
+    for (i = 0; i < json_array_get_length (nodes_jarray); i++) {
+      JsonNode *jnode;
+      GFBGraphNode *node;
+
+      jnode = json_array_get_element (nodes_jarray, i);
+      node = GFBGRAPH_NODE (json_gobject_deserialize (node_type, jnode));
+      nodes_list = g_list_append (nodes_list, node);
+    }
+  }
+
+  g_clear_object (&jparser);
+
+  return nodes_list;
 }
diff --git a/gfbgraph/gfbgraph-connectable.h b/gfbgraph/gfbgraph-connectable.h
index 8b8a601..94cc27c 100644
--- a/gfbgraph/gfbgraph-connectable.h
+++ b/gfbgraph/gfbgraph-connectable.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -24,32 +25,45 @@
 
 G_BEGIN_DECLS
 
-#define GFBGRAPH_TYPE_CONNECTABLE          (gfbgraph_connectable_get_type ())
-#define GFBGRAPH_CONNECTABLE(o)            (G_TYPE_CHECK_INSTANCE_CAST ((o), GFBGRAPH_TYPE_CONNECTABLE, GFBGraphConnectable))
-#define GFBGRAPH_CONNECTABLE_CLASS(k)      (G_TYPE_CHECK_CLASS_CAST((k), GFBGRAPH_TYPE_CONNECTABLE, GFBGraphConnectableInterface))
-#define GFBGRAPH_IS_CONNECTABLE(o)         (G_TYPE_CHECK_INSTANCE_TYPE ((o), GFBGRAPH_TYPE_CONNECTABLE))
-#define GFBGRAPH_CONNECTABLE_GET_IFACE(o)  (G_TYPE_INSTANCE_GET_INTERFACE ((o), GFBGRAPH_TYPE_CONNECTABLE, GFBGraphConnectableInterface))
+#define GFBGRAPH_TYPE_CONNECTABLE (gfbgraph_connectable_get_type ())
+#define GFBGRAPH_CONNECTABLE(o) \
+  (G_TYPE_CHECK_INSTANCE_CAST ((o), GFBGRAPH_TYPE_CONNECTABLE, GFBGraphConnectable))
+#define GFBGRAPH_CONNECTABLE_CLASS(k) \
+  (G_TYPE_CHECK_CLASS_CAST((k), GFBGRAPH_TYPE_CONNECTABLE, GFBGraphConnectableInterface))
+#define GFBGRAPH_IS_CONNECTABLE(o) \
+  (G_TYPE_CHECK_INSTANCE_TYPE ((o), GFBGRAPH_TYPE_CONNECTABLE))
+#define GFBGRAPH_CONNECTABLE_GET_IFACE(o) \
+  (G_TYPE_INSTANCE_GET_INTERFACE ((o), GFBGRAPH_TYPE_CONNECTABLE, GFBGraphConnectableInterface))
 
 typedef struct _GFBGraphConnectable          GFBGraphConnectable;
 typedef struct _GFBGraphConnectableInterface GFBGraphConnectableInterface;
 
 struct _GFBGraphConnectableInterface {
-        GTypeInterface parent;
+  GTypeInterface parent;
 
-        GHashTable *connections;
+  GHashTable *  connections;
 
-        GHashTable   *(*get_connection_post_params) (GFBGraphConnectable *self, GType node_type);
-        GList        *(*parse_connected_data) (GFBGraphConnectable *self, const gchar *payload, GError **error);
+  GHashTable *  (*get_connection_post_params) (GFBGraphConnectable *self,
+                                               GType                node_type);
+  GList *       (*parse_connected_data)       (GFBGraphConnectable  *self,
+                                               const gchar          *payload,
+                                               GError              **error);
 };
 
 GType gfbgraph_connectable_get_type (void) G_GNUC_CONST;
 
-GHashTable*  gfbgraph_connectable_get_connection_post_params   (GFBGraphConnectable *self, GType node_type);
-GList*       gfbgraph_connectable_parse_connected_data         (GFBGraphConnectable *self, const gchar *payload, GError **error);
-
-gboolean     gfbgraph_connectable_is_connectable_to            (GFBGraphConnectable *self, GType node_type);
-const gchar* gfbgraph_connectable_get_connection_path          (GFBGraphConnectable *self, GType node_type);
-GList*       gfbgraph_connectable_default_parse_connected_data (GFBGraphConnectable *self, const gchar *payload, GError **error);
+GHashTable*  gfbgraph_connectable_get_connection_post_params   (GFBGraphConnectable *self,
+                                                                GType                node_type);
+GList*       gfbgraph_connectable_parse_connected_data         (GFBGraphConnectable  *self,
+                                                                const gchar          *payload,
+                                                                GError              **error);
+gboolean     gfbgraph_connectable_is_connectable_to            (GFBGraphConnectable *self,
+                                                                GType                node_type);
+const gchar* gfbgraph_connectable_get_connection_path          (GFBGraphConnectable *self,
+                                                                GType                node_type);
+GList*       gfbgraph_connectable_default_parse_connected_data (GFBGraphConnectable  *self,
+                                                                const gchar          *payload,
+                                                                GError              **error);
 
 G_END_DECLS
 
diff --git a/gfbgraph/gfbgraph-goa-authorizer.c b/gfbgraph/gfbgraph-goa-authorizer.c
index 7d75244..935f3e5 100644
--- a/gfbgraph/gfbgraph-goa-authorizer.c
+++ b/gfbgraph/gfbgraph-goa-authorizer.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -31,209 +32,201 @@
 #include "gfbgraph-goa-authorizer.h"
 
 enum {
-        PROP_O,
-
-        PROP_GOA_OBJECT
+  PROP_O,
+  PROP_GOA_OBJECT
 };
 
 struct _GFBGraphGoaAuthorizerPrivate {
-        GMutex mutex;
-        GoaObject *goa_object;
-        gchar *access_token;
+  GMutex mutex;
+  GoaObject *goa_object;
+  gchar *access_token;
 };
 
-static void gfbgraph_goa_authorizer_class_init            (GFBGraphGoaAuthorizerClass *klass);
-static void gfbgraph_goa_authorizer_init                  (GFBGraphGoaAuthorizer *object);
-static void gfbgraph_goa_authorizer_finalize              (GObject *object);
-static void gfbgraph_goa_authorizer_dispose               (GObject *object);
-static void gfbgraph_goa_authorizer_set_property          (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
-static void gfbgraph_goa_authorizer_get_property          (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
-
-static void gfbgraph_goa_authorizer_iface_init            (GFBGraphAuthorizerInterface *iface);
-void        gfbgraph_goa_authorizer_process_call          (GFBGraphAuthorizer *iface, RestProxyCall *call);
-void        gfbgraph_goa_authorizer_process_message       (GFBGraphAuthorizer *iface, SoupMessage *message);
-gboolean    gfbgraph_goa_authorizer_refresh_authorization (GFBGraphAuthorizer *iface, GCancellable *cancellable, GError **error);
-
-static void gfbgraph_goa_authorizer_set_goa_object        (GFBGraphGoaAuthorizer *self, GoaObject *goa_object);
-
-#define GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_GOA_AUTHORIZER, GFBGraphGoaAuthorizerPrivate))
+#define GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE(o) \
+  (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_GOA_AUTHORIZER, GFBGraphGoaAuthorizerPrivate))
 
 static GObjectClass *parent_class = NULL;
 
+static void authorizer_iface_init (GFBGraphAuthorizerInterface *iface);
+
 G_DEFINE_TYPE_WITH_CODE (GFBGraphGoaAuthorizer, gfbgraph_goa_authorizer, G_TYPE_OBJECT,
-                         G_IMPLEMENT_INTERFACE (GFBGRAPH_TYPE_AUTHORIZER, gfbgraph_goa_authorizer_iface_init));
+  G_IMPLEMENT_INTERFACE (GFBGRAPH_TYPE_AUTHORIZER, authorizer_iface_init));
 
 static void
-gfbgraph_goa_authorizer_class_init (GFBGraphGoaAuthorizerClass *klass)
+gfbgraph_goa_authorizer_finalize (GObject *object)
 {
-        GObjectClass *gobject_class;
-        gobject_class = (GObjectClass*) klass;
-
-        parent_class            = g_type_class_peek_parent (klass);
-        gobject_class->finalize = gfbgraph_goa_authorizer_finalize;
-        gobject_class->get_property = gfbgraph_goa_authorizer_get_property;
-        gobject_class->set_property = gfbgraph_goa_authorizer_set_property;
-        gobject_class->dispose = gfbgraph_goa_authorizer_dispose;
-
-        /**
-         * GFBGraphGoaAuthorizer:goa-object:
-         *
-         * The GOA account providing authentication.
-         *
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_GOA_OBJECT,
-                                         g_param_spec_object ("goa-object",
-                                                              "GoaObject",
-                                                              "The GOA account to authenticate.",
-                                                              GOA_TYPE_OBJECT,
-                                                              G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE));
-
-        g_type_class_add_private (gobject_class, sizeof(GFBGraphGoaAuthorizerPrivate));
+  G_OBJECT_CLASS(parent_class)->finalize (object);
 }
 
 static void
-gfbgraph_goa_authorizer_init (GFBGraphGoaAuthorizer *object)
+gfbgraph_goa_authorizer_dispose (GObject *object)
 {
-        object->priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE(object);
-        g_mutex_init (&object->priv->mutex);
-}
+  GFBGraphGoaAuthorizerPrivate *priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (object);
 
-static void
-gfbgraph_goa_authorizer_finalize (GObject *object)
-{
-        G_OBJECT_CLASS(parent_class)->finalize (object);
+  g_clear_object (&priv->goa_object);
+
+  G_OBJECT_CLASS (parent_class)->dispose (object);
 }
 
 static void
-gfbgraph_goa_authorizer_dispose (GObject *object)
+set_goa_object (GFBGraphGoaAuthorizer *self,
+                GoaObject             *goa_object)
 {
-        GFBGraphGoaAuthorizerPrivate *priv;
+  GoaAccount *account;
+  GoaOAuth2Based *oauth2_based;
+  GFBGraphGoaAuthorizerPrivate *priv;
+
+  g_return_if_fail (GOA_IS_OBJECT (goa_object));
 
-        priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (object);
+  priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (self);
 
-        g_clear_object (&priv->goa_object);
+  oauth2_based = goa_object_peek_oauth2_based (goa_object);
+  g_return_if_fail (oauth2_based != NULL && GOA_IS_OAUTH2_BASED (oauth2_based));
 
-        G_OBJECT_CLASS (parent_class)->dispose (object);
+  account = goa_object_peek_account (goa_object);
+  g_return_if_fail (account != NULL && GOA_IS_ACCOUNT (account));
+
+  g_object_ref (goa_object);
+  priv->goa_object = goa_object;
+}
+
+static void
+gfbgraph_goa_authorizer_set_property (GObject      *object,
+                                      guint         prop_id,
+                                      const GValue *value,
+                                      GParamSpec   *pspec)
+{
+  switch (prop_id) {
+    case PROP_GOA_OBJECT:
+      set_goa_object (GFBGRAPH_GOA_AUTHORIZER (object),
+                      GOA_OBJECT (g_value_get_object (value)));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_goa_authorizer_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+gfbgraph_goa_authorizer_get_property (GObject    *object,
+                                      guint       prop_id,
+                                      GValue     *value,
+                                      GParamSpec *pspec)
 {
-        switch (prop_id) {
-                case PROP_GOA_OBJECT:
-                        gfbgraph_goa_authorizer_set_goa_object (GFBGRAPH_GOA_AUTHORIZER (object), GOA_OBJECT (g_value_get_object (value)));
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  GFBGraphGoaAuthorizerPrivate *priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (object);
+
+  switch (prop_id) {
+    case PROP_GOA_OBJECT:
+      g_value_set_object (value, priv->goa_object);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_goa_authorizer_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+gfbgraph_goa_authorizer_class_init (GFBGraphGoaAuthorizerClass *klass)
 {
-        GFBGraphGoaAuthorizerPrivate *priv;
-
-        priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_GOA_OBJECT:
-                        g_value_set_object (value, priv->goa_object);
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  GObjectClass *gobject_class = (GObjectClass*)klass;
+
+  parent_class            = g_type_class_peek_parent (klass);
+  gobject_class->finalize = gfbgraph_goa_authorizer_finalize;
+  gobject_class->dispose = gfbgraph_goa_authorizer_dispose;
+  gobject_class->get_property = gfbgraph_goa_authorizer_get_property;
+  gobject_class->set_property = gfbgraph_goa_authorizer_set_property;
+
+  /**
+   * GFBGraphGoaAuthorizer:goa-object:
+   *
+   * The GOA account providing authentication.
+   *
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_GOA_OBJECT,
+                                   g_param_spec_object ("goa-object",
+                                                        "GoaObject",
+                                                        "The GOA account to authenticate.",
+                                                        GOA_TYPE_OBJECT,
+                                                        G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE));
+
+  g_type_class_add_private (gobject_class, sizeof(GFBGraphGoaAuthorizerPrivate));
 }
 
 static void
-gfbgraph_goa_authorizer_iface_init (GFBGraphAuthorizerInterface *iface)
+gfbgraph_goa_authorizer_init (GFBGraphGoaAuthorizer *object)
 {
-        iface->process_call = gfbgraph_goa_authorizer_process_call;
-        iface->process_message = gfbgraph_goa_authorizer_process_message;
-        iface->refresh_authorization = gfbgraph_goa_authorizer_refresh_authorization;
+  object->priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE(object);
+  g_mutex_init (&object->priv->mutex);
 }
 
-void
-gfbgraph_goa_authorizer_process_call (GFBGraphAuthorizer *iface, RestProxyCall *call)
+/* --- Authorizer Interface --- */
+static void
+process_call (GFBGraphAuthorizer *iface,
+              RestProxyCall      *call)
 {
-        GFBGraphGoaAuthorizerPrivate *priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (GFBGRAPH_GOA_AUTHORIZER (iface));
+  GFBGraphGoaAuthorizerPrivate *priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (GFBGRAPH_GOA_AUTHORIZER (iface));
 
-        g_mutex_lock (&priv->mutex);
+  g_mutex_lock (&priv->mutex);
 
-        if (priv->access_token != NULL)
-                rest_proxy_call_add_param (call, "access_token", priv->access_token);
+  if (priv->access_token != NULL)
+    rest_proxy_call_add_param (call, "access_token", priv->access_token);
 
-        g_mutex_unlock (&priv->mutex);
+  g_mutex_unlock (&priv->mutex);
 }
 
-void
-gfbgraph_goa_authorizer_process_message (GFBGraphAuthorizer *iface, SoupMessage *message)
+static void
+process_message (GFBGraphAuthorizer *iface,
+                 SoupMessage        *message)
 {
-        gchar *auth_value;
-        SoupURI *uri;
-        GFBGraphGoaAuthorizerPrivate *priv;
-
-        priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (GFBGRAPH_GOA_AUTHORIZER (iface));
+  gchar *auth_value;
+  SoupURI *uri;
+  GFBGraphGoaAuthorizerPrivate *priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (GFBGRAPH_GOA_AUTHORIZER (iface));
 
-        g_mutex_lock (&priv->mutex);
+  g_mutex_lock (&priv->mutex);
 
-        uri = soup_message_get_uri (message);
-        auth_value = g_strconcat ("access_token=", priv->access_token, NULL);
-        soup_uri_set_query (uri, auth_value);
+  uri = soup_message_get_uri (message);
+  auth_value = g_strconcat ("access_token=", priv->access_token, NULL);
+  soup_uri_set_query (uri, auth_value);
 
-        g_free (auth_value);
+  g_free (auth_value);
 
-        g_mutex_unlock (&priv->mutex);
+  g_mutex_unlock (&priv->mutex);
 }
 
-gboolean
-gfbgraph_goa_authorizer_refresh_authorization (GFBGraphAuthorizer *iface, GCancellable *cancellable, GError **error)
+static gboolean
+refresh_authorization (GFBGraphAuthorizer  *iface,
+                       GCancellable        *cancellable,
+                       GError             **error)
 {
-        GFBGraphGoaAuthorizerPrivate *priv;
-        GoaAccount *account;
-        GoaOAuth2Based *oauth2_based;
-        gboolean ret_val;
+  GoaAccount *account;
+  GoaOAuth2Based *oauth2_based;
+  gboolean ret_val = FALSE;
+  GFBGraphGoaAuthorizerPrivate *priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (GFBGRAPH_GOA_AUTHORIZER (iface));
 
-        priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (GFBGRAPH_GOA_AUTHORIZER (iface));
-        ret_val = FALSE;
+  g_mutex_lock (&priv->mutex);
 
-        g_mutex_lock (&priv->mutex);
+  g_free (priv->access_token);
+  priv->access_token = NULL;
 
-        g_free (priv->access_token);
-        priv->access_token = NULL;
+  account = goa_object_peek_account (priv->goa_object);
+  oauth2_based = goa_object_peek_oauth2_based (priv->goa_object);
 
-        account = goa_object_peek_account (priv->goa_object);
-        oauth2_based = goa_object_peek_oauth2_based (priv->goa_object);
+  if (goa_account_call_ensure_credentials_sync (account, NULL, cancellable, error))
+    if (goa_oauth2_based_call_get_access_token_sync (oauth2_based, &priv->access_token, NULL, cancellable, error))
+      ret_val = TRUE;
 
-        if (goa_account_call_ensure_credentials_sync (account, NULL, cancellable, error))
-                if (goa_oauth2_based_call_get_access_token_sync (oauth2_based, &priv->access_token, NULL, cancellable, error))
-                        ret_val = TRUE;
+  g_mutex_unlock (&priv->mutex);
 
-        g_mutex_unlock (&priv->mutex);
-        return ret_val;
+  return ret_val;
 }
 
 static void
-gfbgraph_goa_authorizer_set_goa_object (GFBGraphGoaAuthorizer *self, GoaObject *goa_object)
+authorizer_iface_init (GFBGraphAuthorizerInterface *iface)
 {
-        GoaAccount *account;
-        GoaOAuth2Based *oauth2_based;
-        GFBGraphGoaAuthorizerPrivate *priv;
-
-        g_return_if_fail (GOA_IS_OBJECT (goa_object));
-
-        priv = GFBGRAPH_GOA_AUTHORIZER_GET_PRIVATE (self);
-
-        oauth2_based = goa_object_peek_oauth2_based (goa_object);
-        g_return_if_fail (oauth2_based != NULL && GOA_IS_OAUTH2_BASED (oauth2_based));
-
-        account = goa_object_peek_account (goa_object);
-        g_return_if_fail (account != NULL && GOA_IS_ACCOUNT (account));
-
-        g_object_ref (goa_object);
-        priv->goa_object = goa_object;
+  iface->process_call = process_call;
+  iface->process_message = process_message;
+  iface->refresh_authorization = refresh_authorization;
 }
 
 /**
@@ -244,8 +237,10 @@ gfbgraph_goa_authorizer_set_goa_object (GFBGraphGoaAuthorizer *self, GoaObject *
  *
  * Returns: (transfer full): A new #GFBGraphGoaAuthorizer. Use g_object_unref() to free it.
  */
-GFBGraphGoaAuthorizer*
+GFBGraphGoaAuthorizer *
 gfbgraph_goa_authorizer_new (GoaObject *goa_object)
 {
-        return GFBGRAPH_GOA_AUTHORIZER (g_object_new (GFBGRAPH_TYPE_GOA_AUTHORIZER, "goa-object", goa_object, NULL));
+  return g_object_new (GFBGRAPH_TYPE_GOA_AUTHORIZER,
+                       "goa-object", goa_object,
+                       NULL);
 }
diff --git a/gfbgraph/gfbgraph-goa-authorizer.h b/gfbgraph/gfbgraph-goa-authorizer.h
index fa0fc99..36cf674 100644
--- a/gfbgraph/gfbgraph-goa-authorizer.h
+++ b/gfbgraph/gfbgraph-goa-authorizer.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -25,26 +26,31 @@
 
 G_BEGIN_DECLS
 
-#define GFBGRAPH_TYPE_GOA_AUTHORIZER             (gfbgraph_goa_authorizer_get_type())
-#define GFBGRAPH_GOA_AUTHORIZER(obj)             (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_GOA_AUTHORIZER,GFBGraphGoaAuthorizer))
-#define GFBGRAPH_GOA_AUTHORIZER_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_GOA_AUTHORIZER,GFBGraphGoaAuthorizerClass))
-#define GFBGRAPH_IS_GOA_AUTHORIZER(obj)          (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_GOA_AUTHORIZER))
-#define GFBGRAPH_IS_GOA_AUTHORIZER_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_GOA_AUTHORIZER))
-#define GFBGRAPH_GOA_AUTHORIZER_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_GOA_AUTHORIZER,GFBGraphGoaAuthorizerClass))
+#define GFBGRAPH_TYPE_GOA_AUTHORIZER (gfbgraph_goa_authorizer_get_type())
+#define GFBGRAPH_GOA_AUTHORIZER(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_GOA_AUTHORIZER,GFBGraphGoaAuthorizer))
+#define GFBGRAPH_GOA_AUTHORIZER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_GOA_AUTHORIZER,GFBGraphGoaAuthorizerClass))
+#define GFBGRAPH_IS_GOA_AUTHORIZER(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_GOA_AUTHORIZER))
+#define GFBGRAPH_IS_GOA_AUTHORIZER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_GOA_AUTHORIZER))
+#define GFBGRAPH_GOA_AUTHORIZER_GET_CLASS(obj) \
+  (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_GOA_AUTHORIZER,GFBGraphGoaAuthorizerClass))
 
 typedef struct _GFBGraphGoaAuthorizer        GFBGraphGoaAuthorizer;
 typedef struct _GFBGraphGoaAuthorizerClass   GFBGraphGoaAuthorizerClass;
 typedef struct _GFBGraphGoaAuthorizerPrivate GFBGraphGoaAuthorizerPrivate;
 
 struct _GFBGraphGoaAuthorizer {
-         GObject parent;
+  GObject parent;
 
-        /*< private >*/
-        GFBGraphGoaAuthorizerPrivate *priv;
+  /*< private >*/
+  GFBGraphGoaAuthorizerPrivate *priv;
 };
 
 struct _GFBGraphGoaAuthorizerClass {
-        GObjectClass parent_class;
+  GObjectClass parent_class;
 };
 
 GType                   gfbgraph_goa_authorizer_get_type (void) G_GNUC_CONST;
diff --git a/gfbgraph/gfbgraph-node.c b/gfbgraph/gfbgraph-node.c
index 9ce84bf..6f83ba1 100644
--- a/gfbgraph/gfbgraph-node.c
+++ b/gfbgraph/gfbgraph-node.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -41,215 +42,214 @@
 
 enum
 {
-        PROP_0,
-
-        PROP_ID,
-        PROP_LINK,
-        PROP_CREATEDTIME,
-        PROP_UPDATEDTIME
+  PROP_0,
+  PROP_ID,
+  PROP_LINK,
+  PROP_CREATEDTIME,
+  PROP_UPDATEDTIME
 };
 
 struct _GFBGraphNodePrivate {
-        GList *connections;
-        gchar *id;
-        gchar *link;
-        gchar *created_time;
-        gchar *updated_time;
+  GList *connections;
+  gchar *id;
+  gchar *link;
+  gchar *created_time;
+  gchar *updated_time;
 };
 
 typedef struct {
-        GList *list;
-        GType node_type;
-        GFBGraphAuthorizer *authorizer;
+  GList *list;
+  GType node_type;
+  GFBGraphAuthorizer *authorizer;
 } GFBGraphNodeConnectionAsyncData;
 
-GQuark
-gfbgraph_node_error_quark (void)
-{
-        return g_quark_from_static_string ("gfbgraph-node-error-quark");
-}
-
-static void gfbgraph_node_init         (GFBGraphNode *obj);
-static void gfbgraph_node_class_init   (GFBGraphNodeClass *klass);
-static void gfbgraph_node_finalize     (GObject *object);
-static void gfbgraph_node_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
-static void gfbgraph_node_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
-
-static void gfbgraph_node_connection_async_data_free (GFBGraphNodeConnectionAsyncData *data);
-static void gfbgraph_node_get_connection_nodes_async_thread (GSimpleAsyncResult *simple_async, GFBGraphNode *node, GCancellable cancellable);
-
-#define GFBGRAPH_NODE_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_NODE, GFBGraphNodePrivate))
+#define GFBGRAPH_NODE_GET_PRIVATE(o) \
+  (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_NODE, GFBGraphNodePrivate))
 
 static GObjectClass *parent_class = NULL;
 
 G_DEFINE_TYPE (GFBGraphNode, gfbgraph_node, G_TYPE_OBJECT);
 
-static void
-gfbgraph_node_class_init (GFBGraphNodeClass *klass)
-{
-        GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
-
-        parent_class            = g_type_class_peek_parent (klass);
-
-        gobject_class->finalize = gfbgraph_node_finalize;
-        gobject_class->set_property = gfbgraph_node_set_property;
-        gobject_class->get_property = gfbgraph_node_get_property;
-
-        g_type_class_add_private (gobject_class, sizeof(GFBGraphNodePrivate));
-
-        /**
-         * GFBGraphNode:id:
-         *
-         * The node ID. All nodes have one of this.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_ID,
-                                         g_param_spec_string ("id",
-                                                              "The Facebook node ID", "Every node in the Facebook Graph is identified by his ID",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphNode:link:
-         *
-         * The node link. An URL to the node on Facebook.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_LINK,
-                                         g_param_spec_string ("link",
-                                                              "The link to the node", "A link (url) to the node on Facebook",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphNode:created_time:
-         *
-         * The time the node was initially published. Is an ISO 8601 encoded date.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_CREATEDTIME,
-                                         g_param_spec_string ("created_time",
-                                                              "The node creation time", "An ISO 8601 encoded date when the node was initially published",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphNode:updated_time:
-         *
-         * The last time the node was updated. Is an ISO 8601 encoded date.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_UPDATEDTIME,
-                                         g_param_spec_string ("updated_time",
-                                                              "The node updated time", "An ISO 8601 encoded date when the node was updated",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-}
-
-static void
-gfbgraph_node_init (GFBGraphNode *obj)
+GQuark
+gfbgraph_node_error_quark (void)
 {
-        obj->priv = GFBGRAPH_NODE_GET_PRIVATE(obj);
+  return g_quark_from_static_string ("gfbgraph-node-error-quark");
 }
 
 static void
 gfbgraph_node_finalize (GObject *object)
 {
-        GFBGraphNodePrivate *priv;
-
-        priv = GFBGRAPH_NODE_GET_PRIVATE (object);
+  GFBGraphNodePrivate *priv = GFBGRAPH_NODE_GET_PRIVATE (object);
 
-        if (priv->id)
-                g_free (priv->id);
-        if (priv->link)
-                g_free (priv->link);
-        if (priv->created_time)
-                g_free (priv->created_time);
+  if (priv->id)
+    g_free (priv->id);
+  if (priv->link)
+    g_free (priv->link);
+  if (priv->created_time)
+    g_free (priv->created_time);
 
-        G_OBJECT_CLASS(parent_class)->finalize (object);
+  G_OBJECT_CLASS(parent_class)->finalize (object);
 }
 
 static void
-gfbgraph_node_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+gfbgraph_node_set_property (GObject      *object,
+                            guint         prop_id,
+                            const GValue *value,
+                            GParamSpec   *pspec)
 {
-        GFBGraphNodePrivate *priv;
-
-        priv = GFBGRAPH_NODE_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_ID:
-                        if (priv->id)
-                                g_free (priv->id);
-                        priv->id = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_LINK:
-                        if (priv->link)
-                                g_free (priv->link);
-                        priv->link = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_CREATEDTIME:
-                        if (priv->created_time)
-                                g_free (priv->created_time);
-                        priv->created_time = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_UPDATEDTIME:
-                        if (priv->updated_time)
-                                g_free (priv->updated_time);
-                        priv->updated_time = g_strdup (g_value_get_string (value));
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  GFBGraphNodePrivate *priv = GFBGRAPH_NODE_GET_PRIVATE (object);
+
+  switch (prop_id) {
+    case PROP_ID:
+      if (priv->id)
+        g_free (priv->id);
+      priv->id = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_LINK:
+      if (priv->link)
+        g_free (priv->link);
+      priv->link = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_CREATEDTIME:
+      if (priv->created_time)
+        g_free (priv->created_time);
+      priv->created_time = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_UPDATEDTIME:
+      if (priv->updated_time)
+        g_free (priv->updated_time);
+      priv->updated_time = g_strdup (g_value_get_string (value));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_node_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+gfbgraph_node_get_property (GObject    *object,
+                            guint       prop_id,
+                            GValue     *value,
+                            GParamSpec *pspec)
 {
-        GFBGraphNodePrivate *priv;
-
-        priv = GFBGRAPH_NODE_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_ID:
-                        g_value_set_string (value, priv->id);
-                        break;
-                case PROP_LINK:
-                        g_value_set_string (value, priv->link);
-                        break;
-                case PROP_CREATEDTIME:
-                        g_value_set_string (value, priv->created_time);
-                        break;
-                case PROP_UPDATEDTIME:
-                        g_value_set_string (value, priv->updated_time);
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  GFBGraphNodePrivate *priv = GFBGRAPH_NODE_GET_PRIVATE (object);
+
+  switch (prop_id) {
+    case PROP_ID:
+      g_value_set_string (value, priv->id);
+      break;
+    case PROP_LINK:
+      g_value_set_string (value, priv->link);
+      break;
+    case PROP_CREATEDTIME:
+      g_value_set_string (value, priv->created_time);
+      break;
+    case PROP_UPDATEDTIME:
+      g_value_set_string (value, priv->updated_time);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_node_connection_async_data_free (GFBGraphNodeConnectionAsyncData *data)
+gfbgraph_node_class_init (GFBGraphNodeClass *klass)
 {
-        g_list_free (data->list);
-        g_object_unref (data->authorizer);
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  parent_class            = g_type_class_peek_parent (klass);
+
+  gobject_class->finalize = gfbgraph_node_finalize;
+  gobject_class->set_property = gfbgraph_node_set_property;
+  gobject_class->get_property = gfbgraph_node_get_property;
+
+  g_type_class_add_private (gobject_class, sizeof(GFBGraphNodePrivate));
+
+  /**
+   * GFBGraphNode:id:
+   *
+   * The node ID. All nodes have one of this.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_ID,
+                                   g_param_spec_string ("id",
+                                                        "The Facebook node ID",
+                                                        "Every node in the Facebook Graph is identified by his ID",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphNode:link:
+   *
+   * The node link. An URL to the node on Facebook.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_LINK,
+                                   g_param_spec_string ("link",
+                                                        "The link to the node",
+                                                        "A link (url) to the node on Facebook",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphNode:created_time:
+   *
+   * The time the node was initially published. Is an ISO 8601 encoded date.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_CREATEDTIME,
+                                   g_param_spec_string ("created_time",
+                                                        "The node creation time",
+                                                        "An ISO 8601 encoded date when the node was initially published",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphNode:updated_time:
+   *
+   * The last time the node was updated. Is an ISO 8601 encoded date.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_UPDATEDTIME,
+                                   g_param_spec_string ("updated_time",
+                                                        "The node updated time",
+                                                        "An ISO 8601 encoded date when the node was updated",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+}
 
-        g_slice_free (GFBGraphNodeConnectionAsyncData, data);
+static void
+gfbgraph_node_init (GFBGraphNode *obj)
+{
+  obj->priv = GFBGRAPH_NODE_GET_PRIVATE(obj);
 }
 
+/* --- Private Functions --- */
 static void
-gfbgraph_node_get_connection_nodes_async_thread (GSimpleAsyncResult *simple_async, GFBGraphNode *node, GCancellable cancellable)
+connection_async_data_free (GFBGraphNodeConnectionAsyncData *data)
 {
-        GFBGraphNodeConnectionAsyncData *data;
-        GError *error;
+  g_list_free (data->list);
+  g_object_unref (data->authorizer);
 
-        data = (GFBGraphNodeConnectionAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
+  g_slice_free (GFBGraphNodeConnectionAsyncData, data);
+}
 
-        error = NULL;
-        data->list = gfbgraph_node_get_connection_nodes (node, data->node_type, data->authorizer, &error);
-        if (error != NULL)
-                g_simple_async_result_take_error (simple_async, error);
+static void
+get_connection_nodes_async_thread (GSimpleAsyncResult *simple_async,
+                                   GFBGraphNode       *node,
+                                   GCancellable        cancellable)
+{
+  GFBGraphNodeConnectionAsyncData *data;
+  GError *error = NULL;
+
+  data = (GFBGraphNodeConnectionAsyncData *)g_simple_async_result_get_op_res_gpointer (simple_async);
+  data->list = gfbgraph_node_get_connection_nodes (node,
+                                                   data->node_type,
+                                                   data->authorizer,
+                                                   &error);
+  if (error != NULL)
+    g_simple_async_result_take_error (simple_async, error);
 }
 
 /**
@@ -259,10 +259,10 @@ gfbgraph_node_get_connection_nodes_async_thread (GSimpleAsyncResult *simple_asyn
  *
  * Returns: (transfer full): a new #GFBGraphNode; unref with g_object_unref()
  **/
-GFBGraphNode*
+GFBGraphNode *
 gfbgraph_node_new (void)
 {
-        return GFBGRAPH_NODE (g_object_new (GFBGRAPH_TYPE_NODE, NULL));
+  return GFBGRAPH_NODE (g_object_new (GFBGRAPH_TYPE_NODE, NULL));
 }
 
 /**
@@ -276,38 +276,41 @@ gfbgraph_node_new (void)
  *
  * Returns: (transfer full): a #GFBGraphNode or %NULL.
  **/
-GFBGraphNode*
-gfbgraph_node_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GType node_type, GError **error)
+GFBGraphNode *
+gfbgraph_node_new_from_id (GFBGraphAuthorizer  *authorizer,
+                           const gchar         *id,
+                           GType                node_type,
+                           GError             **error)
 {
-        GFBGraphNode *node;
-        RestProxyCall *rest_call;
-
-        g_return_val_if_fail ((strlen (id) > 0), NULL);
-        g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
-        g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), NULL);
-
-        rest_call = gfbgraph_new_rest_call (authorizer);
-        rest_proxy_call_set_method (rest_call, "GET");
-        rest_proxy_call_set_function (rest_call, id);
-
-        node = NULL;
-        if (rest_proxy_call_sync (rest_call, error)) {
-                JsonParser *jparser;
-                JsonNode *jnode;
-                const gchar *payload;
-
-                payload = rest_proxy_call_get_payload (rest_call);
-                jparser = json_parser_new ();
-                if (json_parser_load_from_data (jparser, payload, -1, error)) {
-                        jnode = json_parser_get_root (jparser);
-                        node = GFBGRAPH_NODE (json_gobject_deserialize (node_type, jnode));
-                }
-
-                g_object_unref (jparser);
-        }
-
-        g_object_unref (rest_call);
-        return node;
+  GFBGraphNode *node = NULL;
+  RestProxyCall *rest_call;
+
+  g_return_val_if_fail ((strlen (id) > 0), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
+  g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), NULL);
+
+  rest_call = gfbgraph_new_rest_call (authorizer);
+  rest_proxy_call_set_method (rest_call, "GET");
+  rest_proxy_call_set_function (rest_call, id);
+
+  if (rest_proxy_call_sync (rest_call, error)) {
+    JsonParser *jparser;
+    JsonNode *jnode;
+    const gchar *payload;
+
+    payload = rest_proxy_call_get_payload (rest_call);
+    jparser = json_parser_new ();
+    if (json_parser_load_from_data (jparser, payload, -1, error)) {
+      jnode = json_parser_get_root (jparser);
+      node = GFBGRAPH_NODE (json_gobject_deserialize (node_type, jnode));
+    }
+
+    g_object_unref (jparser);
+  }
+
+  g_object_unref (rest_call);
+
+  return node;
 }
 
 /**
@@ -318,12 +321,12 @@ gfbgraph_node_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GTyp
  *
  * Returns: (transfer none): the node ID.
  **/
-const gchar*
+const gchar *
 gfbgraph_node_get_id (GFBGraphNode *node)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
 
-        return node->priv->id;
+  return node->priv->id;
 }
 
 /**
@@ -334,12 +337,12 @@ gfbgraph_node_get_id (GFBGraphNode *node)
  *
  * Returns: (transfer none): the URL.
  **/
-const gchar*
+const gchar *
 gfbgraph_node_get_link (GFBGraphNode *node)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
 
-        return node->priv->link;
+  return node->priv->link;
 }
 
 /**
@@ -350,12 +353,12 @@ gfbgraph_node_get_link (GFBGraphNode *node)
  *
  * Returns: (transfer none): an ISO 8601 encoded date when the node was initially published.
  **/
-const gchar*
+const gchar *
 gfbgraph_node_get_created_time (GFBGraphNode *node)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
 
-        return node->priv->created_time;
+  return node->priv->created_time;
 }
 
 /**
@@ -366,12 +369,12 @@ gfbgraph_node_get_created_time (GFBGraphNode *node)
  *
  * Returns: (transfer none): an ISO 8601 encoded date when the node was updated.
  **/
-const gchar*
+const gchar *
 gfbgraph_node_get_updated_time (GFBGraphNode *node)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
 
-        return node->priv->updated_time;
+  return node->priv->updated_time;
 }
 
 /**
@@ -383,14 +386,15 @@ gfbgraph_node_get_updated_time (GFBGraphNode *node)
  * and the Graph API returns the ID of the new created node.
  **/
 void
-gfbgraph_node_set_id (GFBGraphNode *node, const gchar *id)
+gfbgraph_node_set_id (GFBGraphNode *node,
+                      const gchar  *id)
 {
-        g_return_if_fail (GFBGRAPH_IS_NODE (node));
-        g_return_if_fail (id != NULL);
+  g_return_if_fail (GFBGRAPH_IS_NODE (node));
+  g_return_if_fail (id != NULL);
 
-        g_object_set (G_OBJECT (node),
-                      "id", id,
-                      NULL);
+  g_object_set (G_OBJECT (node),
+                "id", id,
+                NULL);
 }
 
 /**
@@ -406,59 +410,61 @@ gfbgraph_node_set_id (GFBGraphNode *node, const gchar *id)
  *
  * Returns: (element-type GFBGraphNode) (transfer full): a newly-allocated #GList of type @node_type objects with the found nodes.
  **/
-GList*
-gfbgraph_node_get_connection_nodes (GFBGraphNode *node, GType node_type, GFBGraphAuthorizer *authorizer, GError **error)
+GList *
+gfbgraph_node_get_connection_nodes (GFBGraphNode        *node,
+                                    GType                node_type,
+                                    GFBGraphAuthorizer  *authorizer,
+                                    GError             **error)
 {
-        GFBGraphNodePrivate *priv;
-        GList *nodes_list = NULL;
-        GFBGraphNode *connected_node;
-        RestProxyCall *rest_call;
-        gchar *function_path;
-
-        g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
-        g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), NULL);
-        g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
-
-        priv = GFBGRAPH_NODE_GET_PRIVATE (node);
-
-        /* Dummy node just for test */
-        connected_node = g_object_new (node_type, NULL);
-        if (GFBGRAPH_IS_CONNECTABLE (connected_node) == FALSE) {
-                g_set_error (error, GFBGRAPH_NODE_ERROR,
-                             GFBGRAPH_NODE_ERROR_NO_CONNECTABLE,
-                             "The given node type (%s) doesn't implement connectable interface", g_type_name (node_type));
-                return NULL;
-        }
-
-        if (gfbgraph_connectable_is_connectable_to (GFBGRAPH_CONNECTABLE (connected_node), G_OBJECT_TYPE (node)) == FALSE) {
-                g_set_error (error, GFBGRAPH_NODE_ERROR,
-                             GFBGRAPH_NODE_ERROR_NO_CONNECTABLE,
-                             "The given node type (%s) can't connect with the node", g_type_name (node_type));
-                return NULL;
-        }
-
-        rest_call = gfbgraph_new_rest_call (authorizer);
-        rest_proxy_call_set_method (rest_call, "GET");
-        function_path = g_strdup_printf ("%s/%s",
-                                         priv->id,
-                                         gfbgraph_connectable_get_connection_path (GFBGRAPH_CONNECTABLE (connected_node),
-                                                                                      G_OBJECT_TYPE (node)));
-        rest_proxy_call_set_function (rest_call, function_path);
-        g_free (function_path);
-
-        if (rest_proxy_call_sync (rest_call, error)) {
-                const gchar *payload;
-
-                payload = rest_proxy_call_get_payload (rest_call);
-                nodes_list = gfbgraph_connectable_parse_connected_data (GFBGRAPH_CONNECTABLE (connected_node), payload, error);
-        }
-
-        /* We don't need this node again */
-        g_object_unref (connected_node);
-        g_object_unref (rest_call);
-
-
-        return nodes_list;
+  GFBGraphNodePrivate *priv;
+  GList *nodes_list = NULL;
+  GFBGraphNode *connected_node;
+  RestProxyCall *rest_call;
+  gchar *function_path;
+
+  g_return_val_if_fail (GFBGRAPH_IS_NODE (node), NULL);
+  g_return_val_if_fail (g_type_is_a (node_type, GFBGRAPH_TYPE_NODE), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
+
+  priv = GFBGRAPH_NODE_GET_PRIVATE (node);
+
+  /* Dummy node just for test */
+  connected_node = g_object_new (node_type, NULL);
+  if (GFBGRAPH_IS_CONNECTABLE (connected_node) == FALSE) {
+    g_set_error (error, GFBGRAPH_NODE_ERROR,
+                 GFBGRAPH_NODE_ERROR_NO_CONNECTABLE,
+                 "The given node type (%s) doesn't implement connectable interface",
+                 g_type_name (node_type));
+    return NULL;
+  }
+
+  if (gfbgraph_connectable_is_connectable_to (GFBGRAPH_CONNECTABLE (connected_node), G_OBJECT_TYPE (node)) == FALSE) {
+    g_set_error (error, GFBGRAPH_NODE_ERROR,
+                 GFBGRAPH_NODE_ERROR_NO_CONNECTABLE,
+                 "The given node type (%s) can't connect with the node",
+                 g_type_name (node_type));
+    return NULL;
+  }
+
+  rest_call = gfbgraph_new_rest_call (authorizer);
+  rest_proxy_call_set_method (rest_call, "GET");
+  function_path = g_strdup_printf ("%s/%s",
+                                   priv->id,
+                                   gfbgraph_connectable_get_connection_path (GFBGRAPH_CONNECTABLE (connected_node),
+                                                                             G_OBJECT_TYPE (node)));
+  rest_proxy_call_set_function (rest_call, function_path);
+  g_free (function_path);
+
+  if (rest_proxy_call_sync (rest_call, error)) {
+    const gchar *payload = rest_proxy_call_get_payload (rest_call);
+    nodes_list = gfbgraph_connectable_parse_connected_data (GFBGRAPH_CONNECTABLE (connected_node), payload, error);
+  }
+
+  /* We don't need this node again */
+  g_object_unref (connected_node);
+  g_object_unref (rest_call);
+
+  return nodes_list;
 }
 
 /**
@@ -477,28 +483,41 @@ gfbgraph_node_get_connection_nodes (GFBGraphNode *node, GType node_type, GFBGrap
  * to get the list of connected nodes.
  **/
 void
-gfbgraph_node_get_connection_nodes_async (GFBGraphNode *node, GType node_type, GFBGraphAuthorizer *authorizer, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data)
+gfbgraph_node_get_connection_nodes_async (GFBGraphNode        *node,
+                                          GType                node_type,
+                                          GFBGraphAuthorizer  *authorizer,
+                                          GCancellable        *cancellable,
+                                          GAsyncReadyCallback  callback,
+                                          gpointer             user_data)
 {
-        GSimpleAsyncResult *result;
-        GFBGraphNodeConnectionAsyncData *data;
-
-        g_return_if_fail (GFBGRAPH_IS_NODE (node));
-        g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
-        g_return_if_fail (callback != NULL);
-
-        result = g_simple_async_result_new (G_OBJECT (node), callback, user_data, gfbgraph_node_get_connection_nodes_async);
-        g_simple_async_result_set_check_cancellable (result, cancellable);
-
-        data = g_slice_new (GFBGraphNodeConnectionAsyncData);
-        data->list = NULL;
-        data->node_type = node_type;
-        data->authorizer = authorizer;
-        g_object_ref (data->authorizer);
-
-        g_simple_async_result_set_op_res_gpointer (result, data, (GDestroyNotify) gfbgraph_node_connection_async_data_free);
-        g_simple_async_result_run_in_thread (result, (GSimpleAsyncThreadFunc) gfbgraph_node_get_connection_nodes_async_thread, G_PRIORITY_DEFAULT, cancellable);
-
-        g_object_unref (result);
+  GSimpleAsyncResult *result;
+  GFBGraphNodeConnectionAsyncData *data;
+
+  g_return_if_fail (GFBGRAPH_IS_NODE (node));
+  g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+  g_return_if_fail (callback != NULL);
+
+  result = g_simple_async_result_new (G_OBJECT (node),
+                                      callback,
+                                      user_data,
+                                      gfbgraph_node_get_connection_nodes_async);
+  g_simple_async_result_set_check_cancellable (result, cancellable);
+
+  data = g_slice_new (GFBGraphNodeConnectionAsyncData);
+  data->list = NULL;
+  data->node_type = node_type;
+  data->authorizer = authorizer;
+  g_object_ref (data->authorizer);
+
+  g_simple_async_result_set_op_res_gpointer (result,
+                                             data,
+                                             (GDestroyNotify)connection_async_data_free);
+  g_simple_async_result_run_in_thread (result,
+                                       (GSimpleAsyncThreadFunc)get_connection_nodes_async_thread,
+                                       G_PRIORITY_DEFAULT,
+                                       cancellable);
+
+  g_object_unref (result);
 }
 
 /**
@@ -513,21 +532,23 @@ gfbgraph_node_get_connection_nodes_async (GFBGraphNode *node, GType node_type, G
  * Returns: (element-type GFBGraphNode) (transfer full): a newly-allocated #GList of type #node_type objects with the found nodes.
  **/
 GList*
-gfbgraph_node_get_connection_nodes_async_finish (GFBGraphNode *node, GAsyncResult *result, GError **error)
+gfbgraph_node_get_connection_nodes_async_finish (GFBGraphNode  *node,
+                                                 GAsyncResult  *result,
+                                                 GError       **error)
 {
-        GSimpleAsyncResult *simple_async;
-        GFBGraphNodeConnectionAsyncData *data;
+  GSimpleAsyncResult *simple_async;
+  GFBGraphNodeConnectionAsyncData *data;
 
-        g_return_val_if_fail (g_simple_async_result_is_valid (result, G_OBJECT (node), gfbgraph_node_get_connection_nodes_async), NULL);
-        g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+  g_return_val_if_fail (g_simple_async_result_is_valid (result, G_OBJECT (node), gfbgraph_node_get_connection_nodes_async), NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
 
-        simple_async = G_SIMPLE_ASYNC_RESULT (result);
+  simple_async = G_SIMPLE_ASYNC_RESULT (result);
 
-        if (g_simple_async_result_propagate_error (simple_async, error))
-                return NULL;
+  if (g_simple_async_result_propagate_error (simple_async, error))
+    return NULL;
 
-        data = (GFBGraphNodeConnectionAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
-        return data->list;
+  data = (GFBGraphNodeConnectionAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
+  return data->list;
 }
 
 /**
@@ -543,79 +564,85 @@ gfbgraph_node_get_connection_nodes_async_finish (GFBGraphNode *node, GAsyncResul
  * Returns: TRUE on sucess, FALSE if an error ocurred.
  **/
 gboolean
-gfbgraph_node_append_connection (GFBGraphNode *node, GFBGraphNode *connect_node, GFBGraphAuthorizer *authorizer, GError **error)
+gfbgraph_node_append_connection (GFBGraphNode        *node,
+                                 GFBGraphNode        *connect_node,
+                                 GFBGraphAuthorizer  *authorizer,
+                                 GError             **error)
 {
-        GFBGraphNodePrivate *priv;
-        RestProxyCall *rest_call;
-        GHashTable *params;
-        gchar *function_path;
-        gboolean success;
-
-        g_return_val_if_fail (GFBGRAPH_IS_NODE (node), FALSE);
-        g_return_val_if_fail (GFBGRAPH_IS_NODE (connect_node), FALSE);
-        g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), FALSE);
-
-        if (GFBGRAPH_IS_CONNECTABLE (connect_node) == FALSE) {
-                g_set_error (error, GFBGRAPH_NODE_ERROR,
-                             GFBGRAPH_NODE_ERROR_NO_CONNECTABLE,
-                             "The given node type (%s) doesn't implement connectable interface", G_OBJECT_TYPE_NAME (connect_node));
-                return FALSE;
-        }
-
-        if (gfbgraph_connectable_is_connectable_to (GFBGRAPH_CONNECTABLE (connect_node), G_OBJECT_TYPE (node)) == FALSE) {
-                g_set_error (error, GFBGRAPH_NODE_ERROR,
-                             GFBGRAPH_NODE_ERROR_NO_CONNECTABLE,
-                             "The given node type (%s) can't append a %s connection", G_OBJECT_TYPE_NAME (node), G_OBJECT_TYPE_NAME (connect_node));
-                return FALSE;
-        }
-
-        priv = GFBGRAPH_NODE_GET_PRIVATE (node);
-
-        success = FALSE;
-        rest_call = gfbgraph_new_rest_call (authorizer);
-        rest_proxy_call_set_method (rest_call, "POST");
-        function_path = g_strdup_printf ("%s/%s",
-                                         priv->id,
-                                         gfbgraph_connectable_get_connection_path (GFBGRAPH_CONNECTABLE (connect_node),
-                                                                                   G_OBJECT_TYPE (node)));
-        rest_proxy_call_set_function (rest_call, function_path);
-        g_free (function_path);
-
-        params = gfbgraph_connectable_get_connection_post_params (GFBGRAPH_CONNECTABLE (connect_node), G_OBJECT_TYPE (node));
-        if (g_hash_table_size (params) > 0) {
-                GHashTableIter iter;
-                const gchar *key;
-                const gchar *value;
-
-                g_hash_table_iter_init (&iter, params);
-                while (g_hash_table_iter_next (&iter, (gpointer *) &key, (gpointer *) &value)) {
-                        rest_proxy_call_add_param (rest_call, key, value);
-                }
-        }
-
-        if (rest_proxy_call_sync (rest_call, error)) {
-                const gchar *payload;
-                JsonParser *jparser;
-                JsonNode *jnode;
-                JsonReader *jreader;
-
-                payload = rest_proxy_call_get_payload (rest_call);
-                /* Parssing the new ID */
-                jparser = json_parser_new ();
-                json_parser_load_from_data (jparser, payload, -1, error);
-                jnode = json_parser_get_root (jparser);
-                jreader = json_reader_new (jnode);
-
-                json_reader_read_element (jreader, 0);
-                gfbgraph_node_set_id (connect_node,
-                                      json_reader_get_string_value (jreader));
-                json_reader_end_element (jreader);
-
-                g_object_unref (jreader);
-                g_object_unref (jparser);
-                success = TRUE;
-        }
-        g_object_unref (rest_call);
-
-        return success;
+  GFBGraphNodePrivate *priv;
+  RestProxyCall *rest_call;
+  GHashTable *params;
+  gchar *function_path;
+  gboolean success = FALSE;
+
+  g_return_val_if_fail (GFBGRAPH_IS_NODE (node), FALSE);
+  g_return_val_if_fail (GFBGRAPH_IS_NODE (connect_node), FALSE);
+  g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), FALSE);
+
+  if (GFBGRAPH_IS_CONNECTABLE (connect_node) == FALSE) {
+    g_set_error (error, GFBGRAPH_NODE_ERROR,
+                 GFBGRAPH_NODE_ERROR_NO_CONNECTABLE,
+                 "The given node type (%s) doesn't implement connectable interface",
+                 G_OBJECT_TYPE_NAME (connect_node));
+    return FALSE;
+  }
+
+  if (gfbgraph_connectable_is_connectable_to (GFBGRAPH_CONNECTABLE (connect_node), G_OBJECT_TYPE (node)) == FALSE) {
+    g_set_error (error, GFBGRAPH_NODE_ERROR,
+                 GFBGRAPH_NODE_ERROR_NO_CONNECTABLE,
+                 "The given node type (%s) can't append a %s connection",
+                 G_OBJECT_TYPE_NAME (node),
+                 G_OBJECT_TYPE_NAME (connect_node));
+    return FALSE;
+  }
+
+  priv = GFBGRAPH_NODE_GET_PRIVATE (node);
+
+  rest_call = gfbgraph_new_rest_call (authorizer);
+  rest_proxy_call_set_method (rest_call, "POST");
+  function_path = g_strdup_printf ("%s/%s",
+                                   priv->id,
+                                   gfbgraph_connectable_get_connection_path (GFBGRAPH_CONNECTABLE (connect_node),
+                                                                             G_OBJECT_TYPE (node)));
+  rest_proxy_call_set_function (rest_call, function_path);
+  g_free (function_path);
+
+  params = gfbgraph_connectable_get_connection_post_params (GFBGRAPH_CONNECTABLE (connect_node),
+                                                            G_OBJECT_TYPE (node));
+  if (g_hash_table_size (params) > 0) {
+    GHashTableIter iter;
+    const gchar *key;
+    const gchar *value;
+
+    g_hash_table_iter_init (&iter, params);
+    while (g_hash_table_iter_next (&iter, (gpointer *) &key, (gpointer *) &value)) {
+      rest_proxy_call_add_param (rest_call, key, value);
+    }
+  }
+
+  if (rest_proxy_call_sync (rest_call, error)) {
+    const gchar *payload;
+    JsonParser *jparser;
+    JsonNode *jnode;
+    JsonReader *jreader;
+
+    payload = rest_proxy_call_get_payload (rest_call);
+    /* Parssing the new ID */
+    jparser = json_parser_new ();
+    json_parser_load_from_data (jparser, payload, -1, error);
+    jnode = json_parser_get_root (jparser);
+    jreader = json_reader_new (jnode);
+
+    json_reader_read_element (jreader, 0);
+    gfbgraph_node_set_id (connect_node,
+        json_reader_get_string_value (jreader));
+    json_reader_end_element (jreader);
+
+    g_object_unref (jreader);
+    g_object_unref (jparser);
+    success = TRUE;
+  }
+  g_object_unref (rest_call);
+
+  return success;
 }
diff --git a/gfbgraph/gfbgraph-node.h b/gfbgraph/gfbgraph-node.h
index c177a82..e637312 100644
--- a/gfbgraph/gfbgraph-node.h
+++ b/gfbgraph/gfbgraph-node.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -25,12 +26,17 @@
 
 G_BEGIN_DECLS
 
-#define GFBGRAPH_TYPE_NODE             (gfbgraph_node_get_type())
-#define GFBGRAPH_NODE(obj)             (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_NODE,GFBGraphNode))
-#define GFBGRAPH_NODE_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_NODE,GFBGraphNodeClass))
-#define GFBGRAPH_IS_NODE(obj)          (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_NODE))
-#define GFBGRAPH_IS_NODE_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_NODE))
-#define GFBGRAPH_NODE_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_NODE,GFBGraphNodeClass))
+#define GFBGRAPH_TYPE_NODE (gfbgraph_node_get_type())
+#define GFBGRAPH_NODE(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_NODE,GFBGraphNode))
+#define GFBGRAPH_NODE_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_NODE,GFBGraphNodeClass))
+#define GFBGRAPH_IS_NODE(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_NODE))
+#define GFBGRAPH_IS_NODE_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_NODE))
+#define GFBGRAPH_NODE_GET_CLASS(obj) \
+  (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_NODE,GFBGraphNodeClass))
 
 #define GFBGRAPH_NODE_ERROR            gfbgraph_node_error_quark ()
 
@@ -41,49 +47,55 @@ typedef struct _GFBGraphNodePrivate GFBGraphNodePrivate;
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (GFBGraphNode, g_object_unref)
 
 struct _GFBGraphNode {
-        GObject parent;
+  GObject parent;
 
-        /*< private >*/
-        GFBGraphNodePrivate *priv;
+  /*< private >*/
+  GFBGraphNodePrivate *priv;
 };
 
 struct _GFBGraphNodeClass {
-        GObjectClass parent_class;
+  GObjectClass parent_class;
 };
 
 typedef enum {
-        GFBGRAPH_NODE_ERROR_NO_CONNECTIONABLE = 1,
-        GFBGRAPH_NODE_ERROR_NO_CONNECTABLE
+  GFBGRAPH_NODE_ERROR_NO_CONNECTIONABLE = 1,
+  GFBGRAPH_NODE_ERROR_NO_CONNECTABLE
 } GFBGraphNodeError;
 
 GType          gfbgraph_node_get_type    (void) G_GNUC_CONST;
 GQuark         gfbgraph_node_error_quark (void) G_GNUC_CONST;
 GFBGraphNode*  gfbgraph_node_new         (void);
 
-GFBGraphNode*  gfbgraph_node_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GType node_type, GError **error);
+GFBGraphNode*  gfbgraph_node_new_from_id (GFBGraphAuthorizer  *authorizer,
+                                          const gchar         *id,
+                                          GType                node_type,
+                                          GError             **error);
 
 const gchar*   gfbgraph_node_get_id           (GFBGraphNode *node);
 const gchar*   gfbgraph_node_get_link         (GFBGraphNode *node);
 const gchar*   gfbgraph_node_get_created_time (GFBGraphNode *node);
 const gchar*   gfbgraph_node_get_updated_time (GFBGraphNode *node);
 
-void           gfbgraph_node_set_id           (GFBGraphNode *node, const gchar *id);
-
-GList*         gfbgraph_node_get_connection_nodes              (GFBGraphNode         *node,
-                                                                GType                 node_type,
-                                                                GFBGraphAuthorizer   *authorizer,
-                                                                GError              **error);
-void           gfbgraph_node_get_connection_nodes_async        (GFBGraphNode         *node, 
-                                                                GType                 node_type, 
-                                                                GFBGraphAuthorizer   *authorizer,
-                                                                GCancellable         *cancellable,
-                                                                GAsyncReadyCallback   callback,
-                                                                gpointer              user_data);
-GList*         gfbgraph_node_get_connection_nodes_async_finish (GFBGraphNode         *node,
-                                                                GAsyncResult         *result,
-                                                                GError              **error);
-
-gboolean       gfbgraph_node_append_connection (GFBGraphNode *node, GFBGraphNode *connect_node, GFBGraphAuthorizer *authorizer, GError **error);
+void           gfbgraph_node_set_id           (GFBGraphNode *node,
+                                               const gchar  *id);
+
+GList*         gfbgraph_node_get_connection_nodes (GFBGraphNode        *node,
+                                                   GType                node_type,
+                                                   GFBGraphAuthorizer  *authorizer,
+                                                   GError             **error);
+void           gfbgraph_node_get_connection_nodes_async (GFBGraphNode        *node,
+                                                         GType                node_type,
+                                                         GFBGraphAuthorizer  *authorizer,
+                                                         GCancellable        *cancellable,
+                                                         GAsyncReadyCallback  callback,
+                                                         gpointer             user_data);
+GList*         gfbgraph_node_get_connection_nodes_async_finish (GFBGraphNode  *node,
+                                                                GAsyncResult  *result,
+                                                                GError       **error);
+gboolean       gfbgraph_node_append_connection (GFBGraphNode        *node,
+                                                GFBGraphNode        *connect_node,
+                                                GFBGraphAuthorizer  *authorizer,
+                                                GError             **error);
 
 G_END_DECLS
 
diff --git a/gfbgraph/gfbgraph-photo.c b/gfbgraph/gfbgraph-photo.c
index 69eb98d..af3cfb6 100644
--- a/gfbgraph/gfbgraph-photo.c
+++ b/gfbgraph/gfbgraph-photo.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -37,331 +38,353 @@
 #include <libsoup/soup-requester.h>
 
 enum {
-        PROP_0,
-
-        PROP_NAME,
-        PROP_SOURCE,
-        PROP_HEIGHT,
-        PROP_WIDTH,
-        PROP_IMAGES
+  PROP_0,
+  PROP_NAME,
+  PROP_SOURCE,
+  PROP_HEIGHT,
+  PROP_WIDTH,
+  PROP_IMAGES
 };
 
 struct _GFBGraphPhotoPrivate {
-        gchar              *name;
-        gchar              *source;
-        guint               width;
-        guint               height;
-        GList              *images;
-        GFBGraphPhotoImage *hires_image;
+  gchar              *name;
+  gchar              *source;
+  guint               width;
+  guint               height;
+  GList              *images;
+  GFBGraphPhotoImage *hires_image;
 };
 
-static void gfbgraph_photo_init         (GFBGraphPhoto *obj);
-static void gfbgraph_photo_class_init   (GFBGraphPhotoClass *klass);
-static void gfbgraph_photo_finalize     (GObject *obj);
-static void gfbgraph_photo_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
-static void gfbgraph_photo_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
-
-static void gfbgraph_photo_connectable_iface_init     (GFBGraphConnectableInterface *iface);
-GHashTable* gfbgraph_photo_get_connection_post_params (GFBGraphConnectable *self, GType node_type);
-
-static void  gfbgraph_photo_serializable_iface_init           (JsonSerializableIface *iface);
-JsonNode    *gfbgraph_photo_serializable_serialize_property   (JsonSerializable *serializable, const gchar *property_name, const GValue *value, GParamSpec *pspec);
-gboolean     gfbgraph_photo_serializable_deserialize_property (JsonSerializable *serializable, const gchar *property_name, GValue *value, GParamSpec *pspec, JsonNode *property_node);
-GParamSpec  *gfbgraph_photo_serializable_find_property        (JsonSerializable *serializable, const char *name);
-GParamSpec **gfbgraph_photo_serializable_list_properties      (JsonSerializable *serializable, guint *n_pspecs);
-void         gfbgraph_photo_serializable_set_property         (JsonSerializable *serializable, GParamSpec *pspec, const GValue *value);
-void         gfbgraph_photo_serializable_get_property         (JsonSerializable *serializable, GParamSpec *pspec, GValue *value);
-
-#define GFBGRAPH_PHOTO_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_PHOTO, GFBGraphPhotoPrivate))
+#define GFBGRAPH_PHOTO_GET_PRIVATE(o) \
+  (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_PHOTO, GFBGraphPhotoPrivate))
 
 static GFBGraphNodeClass *parent_class = NULL;
 
+static void connectable_iface_init   (GFBGraphConnectableInterface *iface);
+static void serializable_iface_init  (JsonSerializableIface *iface);
+
 G_DEFINE_TYPE_WITH_CODE (GFBGraphPhoto, gfbgraph_photo, GFBGRAPH_TYPE_NODE,
-                         G_IMPLEMENT_INTERFACE (GFBGRAPH_TYPE_CONNECTABLE, gfbgraph_photo_connectable_iface_init);
-                         G_IMPLEMENT_INTERFACE (JSON_TYPE_SERIALIZABLE, gfbgraph_photo_serializable_iface_init););
+  G_IMPLEMENT_INTERFACE (GFBGRAPH_TYPE_CONNECTABLE, connectable_iface_init);
+  G_IMPLEMENT_INTERFACE (JSON_TYPE_SERIALIZABLE, serializable_iface_init););
 
 static void
-gfbgraph_photo_init (GFBGraphPhoto *obj)
+gfbgraph_photo_finalize (GObject *obj)
 {
-        obj->priv = GFBGRAPH_PHOTO_GET_PRIVATE(obj);
+  GList *images;
+  GFBGraphPhotoImage *photo_image;
+  GFBGraphPhotoPrivate *priv = GFBGRAPH_PHOTO_GET_PRIVATE (obj);
 
-        obj->priv->images = NULL;
-}
+  images = priv->images;
+  while (images) {
+    photo_image = (GFBGraphPhotoImage *) images->data;
 
-static void
-gfbgraph_photo_class_init (GFBGraphPhotoClass *klass)
-{
-        GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
-
-        parent_class            = g_type_class_peek_parent (klass);
-        gobject_class->finalize = gfbgraph_photo_finalize;
-        gobject_class->set_property = gfbgraph_photo_set_property;
-        gobject_class->get_property = gfbgraph_photo_get_property;
-
-        g_type_class_add_private (gobject_class, sizeof(GFBGraphPhotoPrivate));
-
-        /**
-         * GFBGraphPhoto:name:
-         *
-         * The name of the photo given by his owner.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_NAME,
-                                         g_param_spec_string ("name",
-                                                              "The photo name", "The name given by the user to the photo",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphPhoto:source:
-         *
-         * An URI for the photo, with a maximum width or height of 720px.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_SOURCE,
-                                         g_param_spec_string ("source",
-                                                              "The URI for the photo", "The URI for the photo, with a maximum width or height of 720px",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphPhoto:width:
-         *
-         * The default photo width, up to 720px.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_WIDTH,
-                                         g_param_spec_uint ("width",
-                                                            "Photo width", "The photo width",
-                                                            0, G_MAXUINT, 0,
-                                                            G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphPhoto:height:
-         *
-         * The default photo height, up to 720px.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_HEIGHT,
-                                         g_param_spec_uint ("height",
-                                                            "Photo height", "The photo height",
-                                                            0, G_MAXUINT, 0,
-                                                            G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphPhoto:images:
-         *
-         * A list with the available representations of the photo, in differents sizes
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_IMAGES,
-                                         g_param_spec_pointer ("images",
-                                                               "Sizes of the photo", "The diffents sizes available of the photo",
-                                                               G_PARAM_READABLE | G_PARAM_WRITABLE));
-}
+    g_free (photo_image->source);
+    g_free (photo_image);
 
-static void
-gfbgraph_photo_finalize (GObject *obj)
-{
-        GFBGraphPhotoPrivate *priv;
-        GList *images;
-        GFBGraphPhotoImage *photo_image;
-
-        priv = GFBGRAPH_PHOTO_GET_PRIVATE (obj);
+    images = g_list_next (images);
+  }
 
-        images = priv->images;
-        while (images) {
-                photo_image = (GFBGraphPhotoImage *) images->data;
+  g_free (priv->name);
+  g_free (priv->source);
+  g_list_free (priv->images);
 
-                g_free (photo_image->source);
-                g_free (photo_image);
+  G_OBJECT_CLASS(parent_class)->finalize (obj);
+}
 
-                images = g_list_next (images);
-        }
+static void
+gfbgraph_photo_set_property (GObject      *object,
+                             guint         prop_id,
+                             const GValue *value,
+                             GParamSpec   *pspec)
+{
+  GFBGraphPhotoPrivate *priv = GFBGRAPH_PHOTO_GET_PRIVATE (object);
 
+  switch (prop_id) {
+    case PROP_NAME:
+      if (priv->name)
         g_free (priv->name);
+      priv->name = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_SOURCE:
+      if (priv->source)
         g_free (priv->source);
-        g_list_free (priv->images);
-
-        G_OBJECT_CLASS(parent_class)->finalize (obj);
+      priv->source = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_WIDTH:
+      priv->width = g_value_get_uint (value);
+      break;
+    case PROP_HEIGHT:
+      priv->height = g_value_get_uint (value);
+      break;
+    case PROP_IMAGES:
+      /* TODO: Free GList memory with g_list_free_full */
+      priv->images = g_value_get_pointer (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_photo_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+gfbgraph_photo_get_property (GObject    *object,
+                             guint       prop_id,
+                             GValue     *value,
+                             GParamSpec *pspec)
 {
-        GFBGraphPhotoPrivate *priv;
-
-        priv = GFBGRAPH_PHOTO_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_NAME:
-                        if (priv->name)
-                                g_free (priv->name);
-                        priv->name = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_SOURCE:
-                        if (priv->source)
-                                g_free (priv->source);
-                        priv->source = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_WIDTH:
-                        priv->width = g_value_get_uint (value);
-                        break;
-                case PROP_HEIGHT:
-                        priv->height = g_value_get_uint (value);
-                        break;
-                case PROP_IMAGES:
-                        /* TODO: Free GList memory with g_list_free_full */
-                        priv->images = g_value_get_pointer (value);
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  GFBGraphPhotoPrivate *priv = GFBGRAPH_PHOTO_GET_PRIVATE (object);
+
+  switch (prop_id) {
+    case PROP_NAME:
+      g_value_set_string (value, priv->name);
+      break;
+    case PROP_SOURCE:
+      g_value_set_string (value, priv->source);
+      break;
+    case PROP_WIDTH:
+      g_value_set_uint (value, priv->width);
+      break;
+    case PROP_HEIGHT:
+      g_value_set_uint (value, priv->height);
+      break;
+    case PROP_IMAGES:
+      g_value_set_pointer (value, priv->images);
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_photo_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+gfbgraph_photo_init (GFBGraphPhoto *obj)
 {
-        GFBGraphPhotoPrivate *priv;
-
-        priv = GFBGRAPH_PHOTO_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_NAME:
-                        g_value_set_string (value, priv->name);
-                        break;
-                case PROP_SOURCE:
-                        g_value_set_string (value, priv->source);
-                        break;
-                case PROP_WIDTH:
-                        g_value_set_uint (value, priv->width);
-                        break;
-                case PROP_HEIGHT:
-                        g_value_set_uint (value, priv->height);
-                        break;
-                case PROP_IMAGES:
-                        g_value_set_pointer (value, priv->images);
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  obj->priv = GFBGRAPH_PHOTO_GET_PRIVATE(obj);
+  obj->priv->images = NULL;
 }
 
 static void
-gfbgraph_photo_connectable_iface_init (GFBGraphConnectableInterface *iface)
+gfbgraph_photo_class_init (GFBGraphPhotoClass *klass)
 {
-        GHashTable *connections;
-
-        connections = g_hash_table_new (g_str_hash, g_str_equal);
-        g_hash_table_insert (connections, (gpointer) g_type_name (GFBGRAPH_TYPE_ALBUM), (gpointer) "photos");
-
-        iface->connections = connections;
-        iface->get_connection_post_params = gfbgraph_photo_get_connection_post_params;
-        iface->parse_connected_data = gfbgraph_connectable_default_parse_connected_data;
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  parent_class            = g_type_class_peek_parent (klass);
+  gobject_class->finalize = gfbgraph_photo_finalize;
+  gobject_class->set_property = gfbgraph_photo_set_property;
+  gobject_class->get_property = gfbgraph_photo_get_property;
+
+  g_type_class_add_private (gobject_class, sizeof(GFBGraphPhotoPrivate));
+
+  /**
+   * GFBGraphPhoto:name:
+   *
+   * The name of the photo given by his owner.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_NAME,
+                                   g_param_spec_string ("name",
+                                                        "The photo name",
+                                                        "The name given by the user to the photo",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphPhoto:source:
+   *
+   * An URI for the photo, with a maximum width or height of 720px.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_SOURCE,
+                                   g_param_spec_string ("source",
+                                                        "The URI for the photo",
+                                                        "The URI for the photo, with a maximum width or height of 720px",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphPhoto:width:
+   *
+   * The default photo width, up to 720px.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_WIDTH,
+                                   g_param_spec_uint ("width",
+                                                      "Photo width",
+                                                      "The photo width",
+                                                      0, G_MAXUINT, 0,
+                                                      G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphPhoto:height:
+   *
+   * The default photo height, up to 720px.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_HEIGHT,
+                                   g_param_spec_uint ("height",
+                                                      "Photo height",
+                                                      "The photo height",
+                                                      0, G_MAXUINT, 0,
+                                                      G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphPhoto:images:
+   *
+   * A list with the available representations of the photo, in differents sizes
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_IMAGES,
+                                   g_param_spec_pointer ("images",
+                                                         "Sizes of the photo",
+                                                         "The diffents sizes available of the photo",
+                                                         G_PARAM_READABLE | G_PARAM_WRITABLE));
 }
 
-GHashTable*
-gfbgraph_photo_get_connection_post_params (GFBGraphConnectable *self, GType node_type)
+/* --- Connectable Interface --- */
+GHashTable *
+get_connection_post_params (GFBGraphConnectable *self,
+                                           GType                node_type)
 {
-        GHashTable *params;
-        GFBGraphPhotoPrivate *priv;
-
-        priv = GFBGRAPH_PHOTO_GET_PRIVATE (self);
+  GHashTable *params;
+  GFBGraphPhotoPrivate *priv = GFBGRAPH_PHOTO_GET_PRIVATE (self);
 
-        params = g_hash_table_new (g_str_hash, g_str_equal);
-        g_hash_table_insert (params, "message", priv->name);
-        /* TODO: Incorpate the "source" param (multipart/form-data) */
+  params = g_hash_table_new (g_str_hash, g_str_equal);
+  g_hash_table_insert (params, "message", priv->name);
+  /* TODO: Incorpate the "source" param (multipart/form-data) */
 
-        return params;
+  return params;
 }
 
 static void
-gfbgraph_photo_serializable_iface_init (JsonSerializableIface *iface)
+connectable_iface_init (GFBGraphConnectableInterface *iface)
 {
-        iface->serialize_property   = gfbgraph_photo_serializable_serialize_property;
-        iface->deserialize_property = gfbgraph_photo_serializable_deserialize_property;
-        iface->find_property        = gfbgraph_photo_serializable_find_property;
-        iface->list_properties      = gfbgraph_photo_serializable_list_properties;
-        iface->set_property         = gfbgraph_photo_serializable_set_property;
-        iface->get_property         = gfbgraph_photo_serializable_get_property;
+  GHashTable *connections = g_hash_table_new (g_str_hash, g_str_equal);
+
+  g_hash_table_insert (connections,
+                       (gpointer) g_type_name (GFBGRAPH_TYPE_ALBUM),
+                       (gpointer) "photos");
+
+  iface->connections = connections;
+  iface->get_connection_post_params = get_connection_post_params;
+  iface->parse_connected_data = gfbgraph_connectable_default_parse_connected_data;
 }
 
-JsonNode *
-gfbgraph_photo_serializable_serialize_property (JsonSerializable *serializable, const gchar *property_name, const GValue *value, GParamSpec *pspec)
+/* --- Serializable Interface --- */
+static JsonNode *
+serializable_serialize_property (JsonSerializable *serializable,
+                                 const gchar      *property_name,
+                                 const GValue     *value,
+                                 GParamSpec       *pspec)
 {
-        JsonNode *node = NULL;
+  JsonNode *node = NULL;
 
-        if (g_strcmp0 ("images", property_name) == 0) {
-        } else {
-                node = json_serializable_default_serialize_property (serializable, property_name, value, pspec);
-        }
+  if (g_strcmp0 ("images", property_name) == 0) {
+  } else {
+    node = json_serializable_default_serialize_property (serializable,
+                                                         property_name,
+                                                         value,
+                                                         pspec);
+  }
 
-        return node;
+  return node;
 }
 
-gboolean
-gfbgraph_photo_serializable_deserialize_property (JsonSerializable *serializable, const gchar *property_name, GValue *value, GParamSpec *pspec, JsonNode *property_node)
+static gboolean
+serializable_deserialize_property (JsonSerializable *serializable,
+                                   const gchar      *property_name,
+                                   GValue           *value,
+                                   GParamSpec       *pspec,
+                                   JsonNode         *property_node)
 {
-        gboolean res;
-
-        if (g_strcmp0 ("images", property_name) == 0) {
-                if (JSON_NODE_HOLDS_ARRAY (property_node)) {
-                        guint i, num_images;
-                        JsonArray *jarray;
-                        GList *images;
-
-                        images = NULL;
-                        jarray = json_node_get_array (property_node);
-                        num_images = json_array_get_length (jarray);
-                        for (i = 0; i < num_images; i++) {
-                                JsonObject *image_object;
-                                GFBGraphPhotoImage *photo_image;
-
-                                image_object = json_array_get_object_element (jarray, i);
-                                photo_image = g_new0 (GFBGraphPhotoImage, 1);
-                                photo_image->width = json_object_get_int_member (image_object, "width");
-                                photo_image->height = json_object_get_int_member (image_object, "height");
-                                photo_image->source = g_strdup (json_object_get_string_member (image_object, "source"));
-
-                                images = g_list_append (images, photo_image);
-                        }
-
-                        g_value_set_pointer (value, (gpointer *) images);
-                        res = TRUE;
-                } else {
-                        g_warning ("The 'images' node retrieved from the Facebook Graph API isn't an array, it's holding a %s\n", json_node_type_name (property_node));
-                        res = FALSE;
-                }
-        } else {
-                res = json_serializable_default_deserialize_property (serializable, property_name, value, pspec, property_node);
-        }
-
-        return res;
+  gboolean res;
+
+  if (g_strcmp0 ("images", property_name) == 0) {
+    if (JSON_NODE_HOLDS_ARRAY (property_node)) {
+      guint i, num_images;
+      JsonArray *jarray;
+      GList *images = NULL;
+
+      jarray = json_node_get_array (property_node);
+      num_images = json_array_get_length (jarray);
+      for (i = 0; i < num_images; i++) {
+        JsonObject *image_object;
+        GFBGraphPhotoImage *photo_image;
+
+        image_object = json_array_get_object_element (jarray, i);
+        photo_image = g_new0 (GFBGraphPhotoImage, 1);
+        photo_image->width = json_object_get_int_member (image_object,
+                                                         "width");
+        photo_image->height = json_object_get_int_member (image_object,
+                                                          "height");
+        photo_image->source = g_strdup (json_object_get_string_member (image_object,
+                                                                       "source"));
+
+        images = g_list_append (images, photo_image);
+      }
+
+      g_value_set_pointer (value, (gpointer *) images);
+      res = TRUE;
+    } else {
+      g_warning ("The 'images' node retrieved from the Facebook Graph API isn't an array,"
+                 "it's holding a %s\n",
+                 json_node_type_name (property_node));
+      res = FALSE;
+    }
+  } else {
+    res = json_serializable_default_deserialize_property (serializable,
+                                                          property_name,
+                                                          value,
+                                                          pspec,
+                                                          property_node);
+  }
+
+  return res;
 }
 
-GParamSpec*
-gfbgraph_photo_serializable_find_property (JsonSerializable *serializable, const char *name)
+static GParamSpec *
+serializable_find_property (JsonSerializable *serializable,
+                            const char       *name)
 {
-        return g_object_class_find_property (G_OBJECT_GET_CLASS (GFBGRAPH_PHOTO (serializable)), name);
+  return g_object_class_find_property (G_OBJECT_GET_CLASS (GFBGRAPH_PHOTO (serializable)),
+                                       name);
 }
 
-GParamSpec**
-gfbgraph_photo_serializable_list_properties (JsonSerializable *serializable, guint *n_pspecs)
+static GParamSpec**
+serializable_list_properties (JsonSerializable *serializable,
+                              guint            *n_pspecs)
 {
-        return g_object_class_list_properties (G_OBJECT_GET_CLASS (GFBGRAPH_PHOTO (serializable)), n_pspecs);
+  return g_object_class_list_properties (G_OBJECT_GET_CLASS (GFBGRAPH_PHOTO (serializable)),
+                                         n_pspecs);
 }
 
-void
-gfbgraph_photo_serializable_set_property (JsonSerializable *serializable, GParamSpec *pspec, const GValue *value)
+static void
+serializable_set_property (JsonSerializable *serializable,
+                           GParamSpec       *pspec,
+                           const GValue     *value)
 {
-        g_object_set_property (G_OBJECT (serializable), g_param_spec_get_name (pspec), value);
+  g_object_set_property (G_OBJECT (serializable),
+                         g_param_spec_get_name (pspec),
+                         value);
 }
 
-void
-gfbgraph_photo_serializable_get_property (JsonSerializable *serializable, GParamSpec *pspec, GValue *value)
+static void
+serializable_get_property (JsonSerializable *serializable,
+                           GParamSpec       *pspec,
+                           GValue           *value)
 {
-        g_object_get_property (G_OBJECT (serializable), g_param_spec_get_name (pspec), value);
+  g_object_get_property (G_OBJECT (serializable),
+                         g_param_spec_get_name (pspec),
+                         value);
+}
+
+static void
+serializable_iface_init (JsonSerializableIface *iface)
+{
+  iface->serialize_property   = serializable_serialize_property;
+  iface->deserialize_property = serializable_deserialize_property;
+  iface->find_property        = serializable_find_property;
+  iface->list_properties      = serializable_list_properties;
+  iface->set_property         = serializable_set_property;
+  iface->get_property         = serializable_get_property;
 }
 
 /**
@@ -371,10 +394,10 @@ gfbgraph_photo_serializable_get_property (JsonSerializable *serializable, GParam
  *
  * Returns: (transfer full): a new #GFBGraphPhoto; unref with g_object_unref()
  **/
-GFBGraphPhoto*
+GFBGraphPhoto *
 gfbgraph_photo_new (void)
 {
-        return GFBGRAPH_PHOTO(g_object_new(GFBGRAPH_TYPE_PHOTO, NULL));
+  return GFBGRAPH_PHOTO(g_object_new(GFBGRAPH_TYPE_PHOTO, NULL));
 }
 
 /**
@@ -387,10 +410,15 @@ gfbgraph_photo_new (void)
  *
  * Returns: (transfer full): a new #GFBGraphPhoto; unref with g_object_unref()
  **/
-GFBGraphPhoto*
-gfbgraph_photo_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GError **error)
+GFBGraphPhoto *
+gfbgraph_photo_new_from_id (GFBGraphAuthorizer  *authorizer,
+                            const gchar         *id,
+                            GError             **error)
 {
-        return GFBGRAPH_PHOTO (gfbgraph_node_new_from_id (authorizer, id, GFBGRAPH_TYPE_PHOTO, error));
+  return GFBGRAPH_PHOTO (gfbgraph_node_new_from_id (authorizer,
+                                                    id,
+                                                    GFBGRAPH_TYPE_PHOTO,
+                                                    error));
 }
 
 
@@ -405,41 +433,45 @@ gfbgraph_photo_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GEr
  *
  * Returns: (transfer full): a #GInputStream with the photo content or %NULL in case of error.
  **/
-GInputStream*
-gfbgraph_photo_download_default_size (GFBGraphPhoto *photo, GFBGraphAuthorizer *authorizer, GError **error)
+GInputStream *
+gfbgraph_photo_download_default_size (GFBGraphPhoto       *photo,
+                                      GFBGraphAuthorizer  *authorizer,
+                                      GError             **error)
 {
-        GInputStream *stream = NULL;
-        SoupSession *session;
-        SoupRequester *requester;
-        SoupRequest *request;
-        SoupMessage *message;
-        GFBGraphPhotoPrivate *priv;
+  GInputStream *stream = NULL;
+  SoupSession *session;
+  SoupRequester *requester;
+  SoupRequest *request;
+  SoupMessage *message;
+  GFBGraphPhotoPrivate *priv;
 
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
-        g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
 
-        priv = GFBGRAPH_PHOTO_GET_PRIVATE (photo);
+  priv = GFBGRAPH_PHOTO_GET_PRIVATE (photo);
 
-        session = soup_session_sync_new ();
-        requester = soup_requester_new ();
-        soup_session_add_feature (session, SOUP_SESSION_FEATURE (requester));
+  session = soup_session_sync_new ();
+  requester = soup_requester_new ();
+  soup_session_add_feature (session, SOUP_SESSION_FEATURE (requester));
 
-        request = soup_requester_request (requester, priv->source, error);
-        if (request != NULL) {
-                message = soup_request_http_get_message (SOUP_REQUEST_HTTP (request));
+  request = soup_requester_request (requester, priv->source, error);
+  if (request != NULL) {
+    message = soup_request_http_get_message (SOUP_REQUEST_HTTP (request));
 
-                stream = soup_request_send (request, NULL, error);
-                if (stream != NULL) {
-                        g_object_weak_ref (G_OBJECT (stream), (GWeakNotify) g_object_unref, session);
-                }
+    stream = soup_request_send (request, NULL, error);
+    if (stream != NULL) {
+      g_object_weak_ref (G_OBJECT (stream),
+                         (GWeakNotify)g_object_unref,
+                         session);
+    }
 
-                g_clear_object (&message);
-                g_clear_object (&request);
-        }
+    g_clear_object (&message);
+    g_clear_object (&request);
+  }
 
-        g_clear_object (&requester);
+  g_clear_object (&requester);
 
-        return stream;
+  return stream;
 }
 
 /**
@@ -448,12 +480,12 @@ gfbgraph_photo_download_default_size (GFBGraphPhoto *photo, GFBGraphAuthorizer *
  *
  * Returns: (transfer none): the @photo name, which is the comment given by the user so it would by larger, or %NULL.
  **/
-const gchar*
+const gchar *
 gfbgraph_photo_get_name (GFBGraphPhoto *photo)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
 
-        return photo->priv->name;
+  return photo->priv->name;
 }
 
 /**
@@ -462,12 +494,12 @@ gfbgraph_photo_get_name (GFBGraphPhoto *photo)
  *
  * Returns: (transfer none): the image link with a maximun widht or height of 720px
  **/
-const gchar*
+const gchar *
 gfbgraph_photo_get_default_source_uri (GFBGraphPhoto *photo)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
 
-        return photo->priv->source;
+  return photo->priv->source;
 }
 
 /**
@@ -479,9 +511,9 @@ gfbgraph_photo_get_default_source_uri (GFBGraphPhoto *photo)
 guint
 gfbgraph_photo_get_default_width (GFBGraphPhoto *photo)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), 0);
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), 0);
 
-        return photo->priv->width;
+  return photo->priv->width;
 }
 
 /**
@@ -493,9 +525,9 @@ gfbgraph_photo_get_default_width (GFBGraphPhoto *photo)
 guint
 gfbgraph_photo_get_default_height (GFBGraphPhoto *photo)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), 0);
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), 0);
 
-        return photo->priv->height;
+  return photo->priv->height;
 }
 
 /**
@@ -504,12 +536,12 @@ gfbgraph_photo_get_default_height (GFBGraphPhoto *photo)
  *
  * Returns: (element-type GFBGraphPhotoImage) (transfer none): a #GList of #GFBGraphPhotoImage with the available photo sizes
  **/
-GList*
+GList *
 gfbgraph_photo_get_images (GFBGraphPhoto *photo)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
 
-        return photo->priv->images;
+  return photo->priv->images;
 }
 
 /**
@@ -518,86 +550,83 @@ gfbgraph_photo_get_images (GFBGraphPhoto *photo)
  *
  * Returns: (transfer none): a #GFBGraphPhotoImage with the higher resolution available of the photo
  **/
-const GFBGraphPhotoImage*
+const GFBGraphPhotoImage *
 gfbgraph_photo_get_image_hires (GFBGraphPhoto *photo)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
-
-        if (photo->priv->hires_image == NULL) {
-                GList *images_list;
-                guint bigger_width;
-                GFBGraphPhotoImage *photo_image;
-
-                bigger_width = 0;
-                images_list = photo->priv->images;
-                while (images_list) {
-                        photo_image = (GFBGraphPhotoImage *) images_list->data;
-                        if (photo_image->width > bigger_width) {
-                                photo->priv->hires_image = photo_image;
-                                bigger_width = photo_image->width;
-                        }
-
-                        images_list = g_list_next (images_list);
-                }
-        }
-
-        return photo->priv->hires_image;
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
+
+  if (photo->priv->hires_image == NULL) {
+    GList *images_list;
+    guint bigger_width;
+    GFBGraphPhotoImage *photo_image;
+
+    bigger_width = 0;
+    images_list = photo->priv->images;
+    while (images_list) {
+      photo_image = (GFBGraphPhotoImage *) images_list->data;
+      if (photo_image->width > bigger_width) {
+        photo->priv->hires_image = photo_image;
+        bigger_width = photo_image->width;
+      }
+
+      images_list = g_list_next (images_list);
+    }
+  }
+
+  return photo->priv->hires_image;
 }
 
-const GFBGraphPhotoImage*
-gfbgraph_photo_get_image_near_width (GFBGraphPhoto *photo, guint width)
+const GFBGraphPhotoImage *
+gfbgraph_photo_get_image_near_width (GFBGraphPhoto *photo,
+                                     guint          width)
 {
-        GList *images_list;
-        GFBGraphPhotoImage *tmp_photo_image;
-        GFBGraphPhotoImage *photo_image;
-        gint tmp_w_dif, w_dif;
+  GList *images_list;
+  GFBGraphPhotoImage *tmp_photo_image;
+  GFBGraphPhotoImage *photo_image = NULL;
+  gint tmp_w_dif, w_dif;
 
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
 
-        photo_image = NULL;
-        images_list = photo->priv->images;
-        while (images_list) {
-                tmp_photo_image = (GFBGraphPhotoImage *) images_list->data;
-                tmp_w_dif = tmp_photo_image->width - width;
-                tmp_w_dif = (tmp_w_dif > 0) ? tmp_w_dif : (tmp_w_dif * -1);
+  images_list = photo->priv->images;
+  while (images_list) {
+    tmp_photo_image = (GFBGraphPhotoImage *) images_list->data;
+    tmp_w_dif = tmp_photo_image->width - width;
+    tmp_w_dif = (tmp_w_dif > 0) ? tmp_w_dif : (tmp_w_dif * -1);
 
-                if (photo_image == NULL
-                    || tmp_w_dif < w_dif) {
-                        w_dif = tmp_w_dif;
-                        photo_image = tmp_photo_image;
-                } else {
-                }
+    if (photo_image == NULL || tmp_w_dif < w_dif) {
+      w_dif = tmp_w_dif;
+      photo_image = tmp_photo_image;
+    }
 
-                images_list = g_list_next (images_list);
-        }
+    images_list = g_list_next (images_list);
+  }
 
-        return photo_image;
+  return photo_image;
 }
 
-const GFBGraphPhotoImage*
-gfbgraph_photo_get_image_near_height (GFBGraphPhoto *photo, guint height)
+const GFBGraphPhotoImage *
+gfbgraph_photo_get_image_near_height (GFBGraphPhoto *photo,
+                                      guint          height)
 {
-        GList *images_list;
-        GFBGraphPhotoImage *tmp_photo_image;
-        GFBGraphPhotoImage *photo_image;
-        gint tmp_h_dif, h_dif;
+  GList *images_list;
+  GFBGraphPhotoImage *tmp_photo_image;
+  GFBGraphPhotoImage *photo_image = NULL;
+  gint tmp_h_dif, h_dif;
 
-        g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_PHOTO (photo), NULL);
 
-        photo_image = NULL;
-        images_list = photo->priv->images;
-        while (images_list) {
-                tmp_photo_image = (GFBGraphPhotoImage *) images_list->data;
-                tmp_h_dif = ABS(tmp_photo_image->height - height);
+  images_list = photo->priv->images;
+  while (images_list) {
+    tmp_photo_image = (GFBGraphPhotoImage *) images_list->data;
+    tmp_h_dif = ABS(tmp_photo_image->height - height);
 
-                if (photo_image == NULL
-                    || tmp_h_dif < h_dif) {
-                        h_dif = tmp_h_dif;
-                        photo_image = tmp_photo_image;
-                }
+    if (photo_image == NULL || tmp_h_dif < h_dif) {
+      h_dif = tmp_h_dif;
+      photo_image = tmp_photo_image;
+    }
 
-                images_list = g_list_next (images_list);
-        }
+    images_list = g_list_next (images_list);
+  }
 
-        return photo_image;
+  return photo_image;
 }
diff --git a/gfbgraph/gfbgraph-photo.h b/gfbgraph/gfbgraph-photo.h
index 15932e7..5b947d8 100644
--- a/gfbgraph/gfbgraph-photo.h
+++ b/gfbgraph/gfbgraph-photo.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -25,12 +26,17 @@
 
 G_BEGIN_DECLS
 
-#define GFBGRAPH_TYPE_PHOTO             (gfbgraph_photo_get_type())
-#define GFBGRAPH_PHOTO(obj)             (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_PHOTO,GFBGraphPhoto))
-#define GFBGRAPH_PHOTO_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_PHOTO,GFBGraphPhotoClass))
-#define GFBGRAPH_IS_PHOTO(obj)          (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_PHOTO))
-#define GFBGRAPH_IS_PHOTO_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_PHOTO))
-#define GFBGRAPH_PHOTO_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_PHOTO,GFBGraphPhotoClass))
+#define GFBGRAPH_TYPE_PHOTO (gfbgraph_photo_get_type())
+#define GFBGRAPH_PHOTO(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_PHOTO,GFBGraphPhoto))
+#define GFBGRAPH_PHOTO_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_PHOTO,GFBGraphPhotoClass))
+#define GFBGRAPH_IS_PHOTO(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_PHOTO))
+#define GFBGRAPH_IS_PHOTO_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_PHOTO))
+#define GFBGRAPH_PHOTO_GET_CLASS(obj) \
+  (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_PHOTO,GFBGraphPhotoClass))
 
 typedef struct _GFBGraphPhoto        GFBGraphPhoto;
 typedef struct _GFBGraphPhotoClass   GFBGraphPhotoClass;
@@ -39,14 +45,14 @@ typedef struct _GFBGraphPhotoPrivate GFBGraphPhotoPrivate;
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (GFBGraphPhoto, g_object_unref)
 
 struct _GFBGraphPhoto {
-        GFBGraphNode parent;
+  GFBGraphNode parent;
 
-        /*< private >*/
-        GFBGraphPhotoPrivate *priv;
+  /*< private >*/
+  GFBGraphPhotoPrivate *priv;
 };
 
 struct _GFBGraphPhotoClass {
-        GFBGraphNodeClass parent_class;
+  GFBGraphNodeClass parent_class;
 };
 
 typedef struct _GFBGraphPhotoImage GFBGraphPhotoImage;
@@ -57,15 +63,19 @@ typedef struct _GFBGraphPhotoImage GFBGraphPhotoImage;
  * An struct with the information of a image.
  */
 struct _GFBGraphPhotoImage {
-        guint  width;
-        guint  height;
-        gchar *source;
+  guint  width;
+  guint  height;
+  gchar *source;
 };
 
 GType          gfbgraph_photo_get_type (void) G_GNUC_CONST;
 GFBGraphPhoto* gfbgraph_photo_new      (void);
-GFBGraphPhoto* gfbgraph_photo_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GError **error);
-GInputStream*  gfbgraph_photo_download_default_size (GFBGraphPhoto *photo, GFBGraphAuthorizer *authorizer, GError **error);
+GFBGraphPhoto* gfbgraph_photo_new_from_id (GFBGraphAuthorizer  *authorizer,
+                                           const gchar         *id,
+                                           GError             **error);
+GInputStream*  gfbgraph_photo_download_default_size (GFBGraphPhoto       *photo,
+                                                     GFBGraphAuthorizer  *authorizer,
+                                                     GError             **error);
 
 const gchar*        gfbgraph_photo_get_name               (GFBGraphPhoto *photo);
 const gchar*        gfbgraph_photo_get_default_source_uri (GFBGraphPhoto *photo);
@@ -73,8 +83,10 @@ guint               gfbgraph_photo_get_default_width      (GFBGraphPhoto *photo)
 guint               gfbgraph_photo_get_default_height     (GFBGraphPhoto *photo);
 GList*              gfbgraph_photo_get_images             (GFBGraphPhoto *photo);
 const GFBGraphPhotoImage* gfbgraph_photo_get_image_hires        (GFBGraphPhoto *photo);
-const GFBGraphPhotoImage* gfbgraph_photo_get_image_near_width   (GFBGraphPhoto *photo, guint width);
-const GFBGraphPhotoImage* gfbgraph_photo_get_image_near_height  (GFBGraphPhoto *photo, guint height);
+const GFBGraphPhotoImage* gfbgraph_photo_get_image_near_width   (GFBGraphPhoto *photo,
+                                                                 guint          width);
+const GFBGraphPhotoImage* gfbgraph_photo_get_image_near_height  (GFBGraphPhoto *photo,
+                                                                 guint          height);
 
 G_END_DECLS
 
diff --git a/gfbgraph/gfbgraph-simple-authorizer.c b/gfbgraph/gfbgraph-simple-authorizer.c
index 6e503c4..31202b2 100644
--- a/gfbgraph/gfbgraph-simple-authorizer.c
+++ b/gfbgraph/gfbgraph-simple-authorizer.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -33,162 +34,155 @@
 
 enum
 {
-        PROP_0,
-
-        PROP_ACCESS_TOKEN
+  PROP_0,
+  PROP_ACCESS_TOKEN
 };
 
 struct _GFBGraphSimpleAuthorizerPrivate {
-        GMutex mutex;
-        gchar *access_token;
+  GMutex mutex;
+  gchar *access_token;
 };
 
-static void gfbgraph_simple_authorizer_init         (GFBGraphSimpleAuthorizer *obj);
-static void gfbgraph_simple_authorizer_class_init   (GFBGraphSimpleAuthorizerClass *klass);
-static void gfbgraph_simple_authorizer_finalize     (GObject *obj);
-static void gfbgraph_simple_authorizer_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
-static void gfbgraph_simple_authorizer_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
-
-static void gfbgraph_simple_authorizer_iface_init (GFBGraphAuthorizerInterface *iface);
-
-void     gfbgraph_simple_authorizer_process_call          (GFBGraphAuthorizer *iface, RestProxyCall *call);
-void     gfbgraph_simple_authorizer_process_message       (GFBGraphAuthorizer *iface, SoupMessage *message);
-gboolean gfbgraph_simple_authorizer_refresh_authorization (GFBGraphAuthorizer *iface, GCancellable *cancellable, GError **error);
-
-#define GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_SIMPLE_AUTHORIZER, GFBGraphSimpleAuthorizerPrivate))
+#define GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE(o) \
+  (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_SIMPLE_AUTHORIZER, GFBGraphSimpleAuthorizerPrivate))
 
 static GObjectClass *parent_class = NULL;
 
-G_DEFINE_TYPE_WITH_CODE (GFBGraphSimpleAuthorizer, gfbgraph_simple_authorizer, G_TYPE_OBJECT,
-                         G_IMPLEMENT_INTERFACE (GFBGRAPH_TYPE_AUTHORIZER, gfbgraph_simple_authorizer_iface_init));
+static void authorizer_iface_init (GFBGraphAuthorizerInterface *iface);
 
+G_DEFINE_TYPE_WITH_CODE (GFBGraphSimpleAuthorizer, gfbgraph_simple_authorizer, G_TYPE_OBJECT,
+  G_IMPLEMENT_INTERFACE (GFBGRAPH_TYPE_AUTHORIZER, authorizer_iface_init));
 
 static void
-gfbgraph_simple_authorizer_init (GFBGraphSimpleAuthorizer *obj)
+gfbgraph_simple_authorizer_finalize (GObject *obj)
 {
-        obj->priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE(obj);
-        g_mutex_init (&obj->priv->mutex);
-}
+  GFBGraphSimpleAuthorizerPrivate *priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (obj);
 
-static void
-gfbgraph_simple_authorizer_class_init (GFBGraphSimpleAuthorizerClass *klass)
-{
-        GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
-
-        parent_class            = g_type_class_peek_parent (klass);
-        gobject_class->finalize = gfbgraph_simple_authorizer_finalize;
-        gobject_class->set_property = gfbgraph_simple_authorizer_set_property;
-        gobject_class->get_property = gfbgraph_simple_authorizer_get_property;
-
-        g_type_class_add_private (gobject_class, sizeof(GFBGraphSimpleAuthorizerPrivate));
-
-        /**
-         * GFBGraphSimpleAuthorizer:access_token:
-         *
-         * The access token for the Facebook Graph API, normally, take it by hand in the 
-         * Graph API explorer tool: https://developers.facebook.com/tools/explorer.
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_ACCESS_TOKEN,
-                                         g_param_spec_string ("access-token",
-                                                              "The access token", "The access token for the Facebook Graph API.",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
+  g_free (priv->access_token);
+  g_mutex_clear (&priv->mutex);
+
+  G_OBJECT_CLASS(parent_class)->finalize (obj);
 }
 
 static void
-gfbgraph_simple_authorizer_finalize (GObject *obj)
+gfbgraph_simple_authorizer_set_property (GObject      *object,
+                                         guint         prop_id,
+                                         const GValue *value,
+                                         GParamSpec   *pspec)
 {
-        GFBGraphSimpleAuthorizerPrivate *priv;
-
-        priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (obj);
+  GFBGraphSimpleAuthorizerPrivate *priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (object);
 
+  switch (prop_id) {
+    case PROP_ACCESS_TOKEN:
+      if (priv->access_token)
         g_free (priv->access_token);
-        g_mutex_clear (&priv->mutex);
-
-        G_OBJECT_CLASS(parent_class)->finalize (obj);
+      priv->access_token = g_strdup (g_value_get_string (value));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_simple_authorizer_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+gfbgraph_simple_authorizer_get_property (GObject    *object,
+                                         guint       prop_id,
+                                         GValue     *value,
+                                         GParamSpec *pspec)
 {
-        GFBGraphSimpleAuthorizerPrivate *priv;
-
-        priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_ACCESS_TOKEN:
-                        if (priv->access_token)
-                                g_free (priv->access_token);
-                        priv->access_token = g_strdup (g_value_get_string (value));
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  GFBGraphSimpleAuthorizerPrivate *priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (object);
+
+  switch (prop_id) {
+    case PROP_ACCESS_TOKEN:
+      g_value_set_string (value, priv->access_token);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_simple_authorizer_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+gfbgraph_simple_authorizer_init (GFBGraphSimpleAuthorizer *obj)
 {
-        GFBGraphSimpleAuthorizerPrivate *priv;
-
-        priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_ACCESS_TOKEN:
-                        g_value_set_string (value, priv->access_token);
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  obj->priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE(obj);
+  g_mutex_init (&obj->priv->mutex);
 }
 
 static void
-gfbgraph_simple_authorizer_iface_init (GFBGraphAuthorizerInterface *iface)
+gfbgraph_simple_authorizer_class_init (GFBGraphSimpleAuthorizerClass *klass)
 {
-        iface->process_call = gfbgraph_simple_authorizer_process_call;
-        iface->process_message = gfbgraph_simple_authorizer_process_message;
-        iface->refresh_authorization = gfbgraph_simple_authorizer_refresh_authorization;
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  parent_class            = g_type_class_peek_parent (klass);
+  gobject_class->finalize = gfbgraph_simple_authorizer_finalize;
+  gobject_class->set_property = gfbgraph_simple_authorizer_set_property;
+  gobject_class->get_property = gfbgraph_simple_authorizer_get_property;
+
+  g_type_class_add_private (gobject_class, sizeof(GFBGraphSimpleAuthorizerPrivate));
+
+  /**
+   * GFBGraphSimpleAuthorizer:access_token:
+   *
+   * The access token for the Facebook Graph API, normally, take it by hand in the
+   * Graph API explorer tool: https://developers.facebook.com/tools/explorer.
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_ACCESS_TOKEN,
+                                   g_param_spec_string ("access-token",
+                                                        "The access token",
+                                                        "The access token for the Facebook Graph API.",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
 }
 
-void
-gfbgraph_simple_authorizer_process_call (GFBGraphAuthorizer *iface, RestProxyCall *call)
+/* --- Authorizer Interface --- */
+static void
+process_call (GFBGraphAuthorizer *iface,
+              RestProxyCall      *call)
 {
-        GFBGraphSimpleAuthorizerPrivate *priv;
-
-        priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (GFBGRAPH_SIMPLE_AUTHORIZER (iface));
+  GFBGraphSimpleAuthorizerPrivate *priv;
+  priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (GFBGRAPH_SIMPLE_AUTHORIZER (iface));
 
-        g_mutex_lock (&priv->mutex);
-        rest_proxy_call_add_param (call, "access_token", priv->access_token);
-        g_mutex_unlock (&priv->mutex);
+  g_mutex_lock (&priv->mutex);
+  rest_proxy_call_add_param (call, "access_token", priv->access_token);
+  g_mutex_unlock (&priv->mutex);
 }
 
-void
-gfbgraph_simple_authorizer_process_message (GFBGraphAuthorizer *iface, SoupMessage *message)
+static void
+process_message (GFBGraphAuthorizer *iface,
+                 SoupMessage        *message)
 {
-        gchar *auth_value;
-        SoupURI *uri;
-        GFBGraphSimpleAuthorizerPrivate *priv;
+  gchar *auth_value;
+  SoupURI *uri;
+  GFBGraphSimpleAuthorizerPrivate *priv;
+  priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (GFBGRAPH_SIMPLE_AUTHORIZER (iface));
 
-        priv = GFBGRAPH_SIMPLE_AUTHORIZER_GET_PRIVATE (GFBGRAPH_SIMPLE_AUTHORIZER (iface));
+  g_mutex_lock (&priv->mutex);
 
-        g_mutex_lock (&priv->mutex);
+  uri = soup_message_get_uri (message);
+  auth_value = g_strconcat ("access_token=", priv->access_token, NULL);
+  soup_uri_set_query (uri, auth_value);
 
-        uri = soup_message_get_uri (message);
-        auth_value = g_strconcat ("access_token=", priv->access_token, NULL);
-        soup_uri_set_query (uri, auth_value);
+  g_free (auth_value);
 
-        g_free (auth_value);
+  g_mutex_unlock (&priv->mutex);
+}
 
-        g_mutex_unlock (&priv->mutex);
+static gboolean
+refresh_authorization (GFBGraphAuthorizer  *iface,
+                       GCancellable        *cancellable,
+                       GError             **error)
+{
+  return FALSE;
 }
 
-gboolean
-gfbgraph_simple_authorizer_refresh_authorization (GFBGraphAuthorizer *iface, GCancellable *cancellable, GError **error)
+static void
+authorizer_iface_init (GFBGraphAuthorizerInterface *iface)
 {
-        return FALSE;
+  iface->process_call = process_call;
+  iface->process_message = process_message;
+  iface->refresh_authorization = refresh_authorization;
 }
 
 /**
@@ -200,10 +194,12 @@ gfbgraph_simple_authorizer_refresh_authorization (GFBGraphAuthorizer *iface, GCa
  *
  * Returns: (transfer full): a #GFBGraphSimpleAuthorizer.
  **/
-GFBGraphSimpleAuthorizer*
+GFBGraphSimpleAuthorizer *
 gfbgraph_simple_authorizer_new (const gchar *access_token)
 {
-        g_return_val_if_fail (access_token != NULL, NULL);
+  g_return_val_if_fail (access_token != NULL, NULL);
 
-        return GFBGRAPH_SIMPLE_AUTHORIZER (g_object_new (GFBGRAPH_TYPE_SIMPLE_AUTHORIZER, "access-token", access_token, NULL));
+  return GFBGRAPH_SIMPLE_AUTHORIZER (g_object_new (GFBGRAPH_TYPE_SIMPLE_AUTHORIZER,
+                                                   "access-token", access_token,
+                                                   NULL));
 }
diff --git a/gfbgraph/gfbgraph-simple-authorizer.h b/gfbgraph/gfbgraph-simple-authorizer.h
index e2ceac3..56b9cad 100644
--- a/gfbgraph/gfbgraph-simple-authorizer.h
+++ b/gfbgraph/gfbgraph-simple-authorizer.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -24,26 +25,31 @@
 
 G_BEGIN_DECLS
 
-#define GFBGRAPH_TYPE_SIMPLE_AUTHORIZER             (gfbgraph_simple_authorizer_get_type())
-#define GFBGRAPH_SIMPLE_AUTHORIZER(obj)             (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER,GFBGraphSimpleAuthorizer))
-#define GFBGRAPH_SIMPLE_AUTHORIZER_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER,GFBGraphSimpleAuthorizerClass))
-#define GFBGRAPH_IS_SIMPLE_AUTHORIZER(obj)          (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER))
-#define GFBGRAPH_IS_SIMPLE_AUTHORIZER_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER))
-#define GFBGRAPH_SIMPLE_AUTHORIZER_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER,GFBGraphSimpleAuthorizerClass))
+#define GFBGRAPH_TYPE_SIMPLE_AUTHORIZER (gfbgraph_simple_authorizer_get_type())
+#define GFBGRAPH_SIMPLE_AUTHORIZER(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER,GFBGraphSimpleAuthorizer))
+#define GFBGRAPH_SIMPLE_AUTHORIZER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER,GFBGraphSimpleAuthorizerClass))
+#define GFBGRAPH_IS_SIMPLE_AUTHORIZER(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER))
+#define GFBGRAPH_IS_SIMPLE_AUTHORIZER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER))
+#define GFBGRAPH_SIMPLE_AUTHORIZER_GET_CLASS(obj) \
+  (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_SIMPLE_AUTHORIZER,GFBGraphSimpleAuthorizerClass))
 
 typedef struct _GFBGraphSimpleAuthorizer        GFBGraphSimpleAuthorizer;
 typedef struct _GFBGraphSimpleAuthorizerClass   GFBGraphSimpleAuthorizerClass;
 typedef struct _GFBGraphSimpleAuthorizerPrivate GFBGraphSimpleAuthorizerPrivate;
 
 struct _GFBGraphSimpleAuthorizer {
-        GObject parent;
+  GObject parent;
 
-        /*< private >*/
-        GFBGraphSimpleAuthorizerPrivate *priv;
+  /*< private >*/
+  GFBGraphSimpleAuthorizerPrivate *priv;
 };
 
 struct _GFBGraphSimpleAuthorizerClass {
-        GObjectClass parent_class;
+  GObjectClass parent_class;
 };
 
 GType                     gfbgraph_simple_authorizer_get_type (void) G_GNUC_CONST;
diff --git a/gfbgraph/gfbgraph-user.c b/gfbgraph/gfbgraph-user.c
index 92b43b2..4a85f65 100644
--- a/gfbgraph/gfbgraph-user.c
+++ b/gfbgraph/gfbgraph-user.c
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013-2014 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -36,178 +37,177 @@
 #define ME_FUNCTION "me"
 
 enum {
-        PROP_0,
-
-        PROP_NAME,
-        PROP_EMAIL
+  PROP_0,
+  PROP_NAME,
+  PROP_EMAIL
 };
 
 struct _GFBGraphUserPrivate {
-        gchar *name;
-        gchar *email;
+  gchar *name;
+  gchar *email;
 };
 
 typedef struct {
-        GFBGraphUser *user;
+  GFBGraphUser *user;
 } GFBGraphUserAsyncData;
 
 typedef struct {
-        GFBGraphAuthorizer *authorizer;
-        GList *nodes;
+  GFBGraphAuthorizer *authorizer;
+  GList *nodes;
 } GFBGraphUserConnectionAsyncData;
 
-static void gfbgraph_user_init         (GFBGraphUser *object);
-static void gfbgraph_user_class_init   (GFBGraphUserClass *klass);
-static void gfbgraph_user_finalize     (GObject *object);
-static void gfbgraph_user_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
-static void gfbgraph_user_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
-
-/* Private functions */
-static void gfbgraph_user_async_data_free (GFBGraphUserAsyncData *data);
-static void gfbgraph_user_connection_async_data_free (GFBGraphUserConnectionAsyncData *data);
-static void gfbgraph_user_get_me_async_thread (GSimpleAsyncResult *simple_async, GFBGraphAuthorizer *authorizer, GCancellable cancellable);
-static void gfbgraph_user_get_albums_async_thread (GSimpleAsyncResult *simple_async, GFBGraphUser *user, GCancellable cancellable);
-
-#define GFBGRAPH_USER_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_USER, GFBGraphUserPrivate))
+#define GFBGRAPH_USER_GET_PRIVATE(o) \
+  (G_TYPE_INSTANCE_GET_PRIVATE((o), GFBGRAPH_TYPE_USER, GFBGraphUserPrivate))
 
 static GFBGraphNodeClass *parent_class = NULL;
 
 G_DEFINE_TYPE (GFBGraphUser, gfbgraph_user, GFBGRAPH_TYPE_NODE);
 
 static void
-gfbgraph_user_init (GFBGraphUser *object)
+gfbgraph_user_finalize (GObject *object)
 {
-        object->priv = GFBGRAPH_USER_GET_PRIVATE (object);
-}
+  GFBGraphUserPrivate *priv = GFBGRAPH_USER_GET_PRIVATE (object);
 
-static void
-gfbgraph_user_class_init (GFBGraphUserClass *klass)
-{
-        GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
-
-        parent_class            = g_type_class_peek_parent (klass);
-        gobject_class->finalize = gfbgraph_user_finalize;
-        gobject_class->set_property = gfbgraph_user_set_property;
-        gobject_class->get_property = gfbgraph_user_get_property;
-
-        g_type_class_add_private (gobject_class, sizeof(GFBGraphUserPrivate));
-
-        /**
-         * GFBGraphUser:name:
-         *
-         * The full name of the user
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_NAME,
-                                         g_param_spec_string ("name",
-                                                              "User's full name", "The full name of the user",
-                                                              "",
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
-
-        /**
-         * GFBGraphUser:email:
-         *
-         * The email of the user if available
-         **/
-        g_object_class_install_property (gobject_class,
-                                         PROP_EMAIL,
-                                         g_param_spec_string ("email",
-                                                              "User's email", "The user primary email if available",
-                                                              NULL,
-                                                              G_PARAM_READABLE | G_PARAM_WRITABLE));
+  g_free (priv->name);
+  g_free (priv->email);
+
+  G_OBJECT_CLASS(parent_class)->finalize (object);
 }
 
 static void
-gfbgraph_user_finalize (GObject *object)
+gfbgraph_user_set_property (GObject      *object,
+                            guint         prop_id,
+                            const GValue *value,
+                            GParamSpec   *pspec)
 {
-        GFBGraphUserPrivate *priv = GFBGRAPH_USER_GET_PRIVATE (object);
+  GFBGraphUserPrivate *priv = GFBGRAPH_USER_GET_PRIVATE (object);
 
+  switch (prop_id) {
+    case PROP_NAME:
+      if (priv->name)
         g_free (priv->name);
+      priv->name = g_strdup (g_value_get_string (value));
+      break;
+    case PROP_EMAIL:
+      if (priv->email)
         g_free (priv->email);
+      priv->email = g_strdup (g_value_get_string (value));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
 
-        G_OBJECT_CLASS(parent_class)->finalize (object);
+static void
+gfbgraph_user_get_property (GObject    *object,
+                            guint       prop_id,
+                            GValue     *value,
+                            GParamSpec *pspec)
+{
+  GFBGraphUserPrivate *priv = GFBGRAPH_USER_GET_PRIVATE (object);
+
+  switch (prop_id) {
+    case PROP_NAME:
+      g_value_set_string (value, priv->name);
+      break;
+    case PROP_EMAIL:
+      g_value_set_string (value, priv->email);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
 }
 
 static void
-gfbgraph_user_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+gfbgraph_user_init (GFBGraphUser *object)
 {
-        GFBGraphUserPrivate *priv = GFBGRAPH_USER_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_NAME:
-                        if (priv->name)
-                                g_free (priv->name);
-                        priv->name = g_strdup (g_value_get_string (value));
-                        break;
-                case PROP_EMAIL:
-                        if (priv->email)
-                                g_free (priv->email);
-                        priv->email = g_strdup (g_value_get_string (value));
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  object->priv = GFBGRAPH_USER_GET_PRIVATE (object);
 }
 
 static void
-gfbgraph_user_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+gfbgraph_user_class_init (GFBGraphUserClass *klass)
 {
-        GFBGraphUserPrivate *priv = GFBGRAPH_USER_GET_PRIVATE (object);
-
-        switch (prop_id) {
-                case PROP_NAME:
-                        g_value_set_string (value, priv->name);
-                        break;
-                case PROP_EMAIL:
-                        g_value_set_string (value, priv->email);
-                        break;
-                default:
-                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
-                        break;
-        }
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  parent_class            = g_type_class_peek_parent (klass);
+  gobject_class->finalize = gfbgraph_user_finalize;
+  gobject_class->set_property = gfbgraph_user_set_property;
+  gobject_class->get_property = gfbgraph_user_get_property;
+
+  g_type_class_add_private (gobject_class, sizeof(GFBGraphUserPrivate));
+
+  /**
+   * GFBGraphUser:name:
+   *
+   * The full name of the user
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_NAME,
+                                   g_param_spec_string ("name",
+                                                        "User's full name",
+                                                        "The full name of the user",
+                                                        "",
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
+
+  /**
+   * GFBGraphUser:email:
+   *
+   * The email of the user if available
+   **/
+  g_object_class_install_property (gobject_class,
+                                   PROP_EMAIL,
+                                   g_param_spec_string ("email",
+                                                        "User's email",
+                                                        "The user primary email if available",
+                                                        NULL,
+                                                        G_PARAM_READABLE | G_PARAM_WRITABLE));
 }
 
+/* --- Private Functions --- */
 static void
-gfbgraph_user_async_data_free (GFBGraphUserAsyncData *data)
+async_data_free (GFBGraphUserAsyncData *data)
 {
-        g_object_unref (data->user);
+  g_object_unref (data->user);
 
-        g_slice_free (GFBGraphUserAsyncData, data);
+  g_slice_free (GFBGraphUserAsyncData, data);
 }
 
 static void
-gfbgraph_user_connection_async_data_free (GFBGraphUserConnectionAsyncData *data)
+connection_async_data_free (GFBGraphUserConnectionAsyncData *data)
 {
-        g_object_unref (data->authorizer);
+  g_object_unref (data->authorizer);
 
-        g_slice_free (GFBGraphUserConnectionAsyncData, data);
+  g_slice_free (GFBGraphUserConnectionAsyncData, data);
 }
 
 static void
-gfbgraph_user_get_me_async_thread (GSimpleAsyncResult *simple_async, GFBGraphAuthorizer *authorizer, GCancellable cancellable)
+get_me_async_thread (GSimpleAsyncResult *simple_async,
+                     GFBGraphAuthorizer *authorizer,
+                     GCancellable        cancellable)
 {
-        GFBGraphUserAsyncData *data;
-        GError *error = NULL;
+  GFBGraphUserAsyncData *data;
+  GError *error = NULL;
 
-        data = (GFBGraphUserAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
-
-        data->user = gfbgraph_user_get_me (authorizer, &error);
-        if (error != NULL)
-                g_simple_async_result_take_error (simple_async, error);
+  data = (GFBGraphUserAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
+  data->user = gfbgraph_user_get_me (authorizer, &error);
+  if (error != NULL)
+    g_simple_async_result_take_error (simple_async, error);
 }
 
 static void
-gfbgraph_user_get_albums_async_thread (GSimpleAsyncResult *simple_async, GFBGraphUser *user, GCancellable cancellable)
+get_albums_async_thread (GSimpleAsyncResult *simple_async,
+                         GFBGraphUser       *user,
+                         GCancellable        cancellable)
 {
-        GFBGraphUserConnectionAsyncData *data;
-        GError *error = NULL;
-
-        data = (GFBGraphUserConnectionAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
+  GFBGraphUserConnectionAsyncData *data;
+  GError *error = NULL;
 
-        data->nodes = gfbgraph_user_get_albums (user, data->authorizer, &error);
-        if (error != NULL)
-                g_simple_async_result_take_error (simple_async, error);
+  data = (GFBGraphUserConnectionAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
+  data->nodes = gfbgraph_user_get_albums (user, data->authorizer, &error);
+  if (error != NULL)
+    g_simple_async_result_take_error (simple_async, error);
 }
 
 /**
@@ -217,10 +217,10 @@ gfbgraph_user_get_albums_async_thread (GSimpleAsyncResult *simple_async, GFBGrap
  *
  * Returns: a new #GFBGraphUser; unref with g_object_unref()
  **/
-GFBGraphUser*
+GFBGraphUser *
 gfbgraph_user_new (void)
 {
-        return GFBGRAPH_USER (g_object_new (GFBGRAPH_TYPE_USER, NULL));
+  return GFBGRAPH_USER (g_object_new (GFBGRAPH_TYPE_USER, NULL));
 }
 
 /**
@@ -233,10 +233,15 @@ gfbgraph_user_new (void)
  *
  * Returns: (transfer full): a new #GFBGraphUser; unref with g_object_unref()
  **/
-GFBGraphUser*
-gfbgraph_user_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GError **error)
+GFBGraphUser *
+gfbgraph_user_new_from_id (GFBGraphAuthorizer  *authorizer,
+                           const gchar         *id,
+                           GError             **error)
 {
-        return GFBGRAPH_USER (gfbgraph_node_new_from_id (authorizer, id, GFBGRAPH_TYPE_USER, error));
+  return GFBGRAPH_USER (gfbgraph_node_new_from_id (authorizer,
+                                                   id,
+                                                   GFBGRAPH_TYPE_USER,
+                                                   error));
 }
 
 /**
@@ -249,38 +254,39 @@ gfbgraph_user_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GErr
  *
  * Returns: (transfer full): a #GFBGraphUser with the current user information.
  **/
-GFBGraphUser*
-gfbgraph_user_get_me (GFBGraphAuthorizer *authorizer, GError **error)
+GFBGraphUser *
+gfbgraph_user_get_me (GFBGraphAuthorizer  *authorizer,
+                      GError             **error)
 {
-        GFBGraphUser *me = NULL;
-        RestProxyCall *rest_call;
-        const gchar *payload;
-        gboolean result;
-
-        g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
-
-        rest_call = gfbgraph_new_rest_call (authorizer);
-        rest_proxy_call_set_function (rest_call, ME_FUNCTION);
-        rest_proxy_call_set_method (rest_call, "GET");
-        rest_proxy_call_add_param (rest_call, "fields", "name,email");
-
-        result = rest_proxy_call_sync (rest_call, error);
-        if (result) {
-                JsonParser *parser;
-                JsonNode *node;
-
-                payload = rest_proxy_call_get_payload (rest_call);
-                parser = json_parser_new ();
-                if (json_parser_load_from_data (parser, payload, -1, error)) {
-                        node = json_parser_get_root (parser);
-                        me = GFBGRAPH_USER (json_gobject_deserialize (GFBGRAPH_TYPE_USER, node));
-                }
-
-                g_object_unref (parser);
-        }
-        g_object_unref (rest_call);
-
-        return me;
+  GFBGraphUser *me = NULL;
+  RestProxyCall *rest_call;
+  const gchar *payload;
+  gboolean result;
+
+  g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
+
+  rest_call = gfbgraph_new_rest_call (authorizer);
+  rest_proxy_call_set_function (rest_call, ME_FUNCTION);
+  rest_proxy_call_set_method (rest_call, "GET");
+  rest_proxy_call_add_param (rest_call, "fields", "name,email");
+
+  result = rest_proxy_call_sync (rest_call, error);
+  if (result) {
+    JsonParser *parser;
+    JsonNode *node;
+
+    payload = rest_proxy_call_get_payload (rest_call);
+    parser = json_parser_new ();
+    if (json_parser_load_from_data (parser, payload, -1, error)) {
+      node = json_parser_get_root (parser);
+      me = GFBGRAPH_USER (json_gobject_deserialize (GFBGRAPH_TYPE_USER, node));
+    }
+
+    g_object_unref (parser);
+  }
+  g_object_unref (rest_call);
+
+  return me;
 }
 
 /**
@@ -297,25 +303,36 @@ gfbgraph_user_get_me (GFBGraphAuthorizer *authorizer, GError **error)
  * to get the #GFBGraphUser for to the current user logged.
  **/
 void
-gfbgraph_user_get_me_async (GFBGraphAuthorizer *authorizer, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data)
+gfbgraph_user_get_me_async (GFBGraphAuthorizer  *authorizer,
+                            GCancellable        *cancellable,
+                            GAsyncReadyCallback  callback,
+                            gpointer             user_data)
 {
-        GSimpleAsyncResult *simple_async;
-        GFBGraphUserAsyncData *data;
-
-        g_return_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer));
-        g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
-        g_return_if_fail (callback != NULL);
-
-        simple_async = g_simple_async_result_new (G_OBJECT (authorizer), callback, user_data, gfbgraph_user_get_me_async);
-        g_simple_async_result_set_check_cancellable (simple_async, cancellable);
-
-        data = g_slice_new (GFBGraphUserAsyncData);
-        data->user = NULL;
-
-        g_simple_async_result_set_op_res_gpointer (simple_async, data, (GDestroyNotify) gfbgraph_user_async_data_free);
-        g_simple_async_result_run_in_thread (simple_async, (GSimpleAsyncThreadFunc) gfbgraph_user_get_me_async_thread, G_PRIORITY_DEFAULT, cancellable);
-
-        g_object_unref (simple_async);
+  GSimpleAsyncResult *simple_async;
+  GFBGraphUserAsyncData *data;
+
+  g_return_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer));
+  g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+  g_return_if_fail (callback != NULL);
+
+  simple_async = g_simple_async_result_new (G_OBJECT (authorizer),
+                                            callback,
+                                            user_data,
+                                            gfbgraph_user_get_me_async);
+  g_simple_async_result_set_check_cancellable (simple_async, cancellable);
+
+  data = g_slice_new (GFBGraphUserAsyncData);
+  data->user = NULL;
+
+  g_simple_async_result_set_op_res_gpointer (simple_async,
+                                             data,
+                                             (GDestroyNotify)async_data_free);
+  g_simple_async_result_run_in_thread (simple_async,
+                                       (GSimpleAsyncThreadFunc)get_me_async_thread,
+                                       G_PRIORITY_DEFAULT,
+                                       cancellable);
+
+  g_object_unref (simple_async);
 }
 
 /**
@@ -329,22 +346,27 @@ gfbgraph_user_get_me_async (GFBGraphAuthorizer *authorizer, GCancellable *cancel
  *
  * Returns: (transfer full): a #GFBGraphUser for to the current user logged.
  **/
-GFBGraphUser*
-gfbgraph_user_get_me_async_finish (GFBGraphAuthorizer *authorizer, GAsyncResult *result, GError **error)
+GFBGraphUser *
+gfbgraph_user_get_me_async_finish (GFBGraphAuthorizer  *authorizer,
+                                   GAsyncResult        *result,
+                                   GError             **error)
 {
-        GSimpleAsyncResult *simple_async;
-        GFBGraphUserAsyncData *data;
+  GSimpleAsyncResult *simple_async;
+  GFBGraphUserAsyncData *data;
 
-        g_return_val_if_fail (g_simple_async_result_is_valid (result, G_OBJECT (authorizer), gfbgraph_user_get_me_async), NULL);
-        g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+  g_return_val_if_fail (g_simple_async_result_is_valid (result,
+                                                        G_OBJECT (authorizer),
+                                                        gfbgraph_user_get_me_async),
+                        NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
 
-        simple_async = G_SIMPLE_ASYNC_RESULT (result);
+  simple_async = G_SIMPLE_ASYNC_RESULT (result);
 
-        if (g_simple_async_result_propagate_error (simple_async, error))
-                return NULL;
+  if (g_simple_async_result_propagate_error (simple_async, error))
+    return NULL;
 
-        data = (GFBGraphUserAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
-        return data->user;
+  data = (GFBGraphUserAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
+  return data->user;
 }
 
 /**
@@ -357,13 +379,18 @@ gfbgraph_user_get_me_async_finish (GFBGraphAuthorizer *authorizer, GAsyncResult
  *
  * Returns: (element-type GFBGraphAlbum) (transfer full): a newly-allocated #GList with the albums nodes owned by the given user.
  **/
-GList*
-gfbgraph_user_get_albums (GFBGraphUser *user, GFBGraphAuthorizer *authorizer, GError **error)
+GList *
+gfbgraph_user_get_albums (GFBGraphUser        *user,
+                          GFBGraphAuthorizer  *authorizer,
+                          GError             **error)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_USER (user), NULL);
-        g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_USER (user), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer), NULL);
 
-        return gfbgraph_node_get_connection_nodes (GFBGRAPH_NODE (user), GFBGRAPH_TYPE_ALBUM, authorizer, error);
+  return gfbgraph_node_get_connection_nodes (GFBGRAPH_NODE (user),
+                                             GFBGRAPH_TYPE_ALBUM,
+                                             authorizer,
+                                             error);
 }
 
 /**
@@ -381,28 +408,41 @@ gfbgraph_user_get_albums (GFBGraphUser *user, GFBGraphAuthorizer *authorizer, GE
  * to get the #GList of #GFBGraphAlbum owned by the @user.
  **/
 void
-gfbgraph_user_get_albums_async (GFBGraphUser *user, GFBGraphAuthorizer *authorizer, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data)
+gfbgraph_user_get_albums_async (GFBGraphUser        *user,
+                                GFBGraphAuthorizer  *authorizer,
+                                GCancellable        *cancellable,
+                                GAsyncReadyCallback  callback,
+                                gpointer             user_data)
 {
-        GSimpleAsyncResult *simple_async;
-        GFBGraphUserConnectionAsyncData *data;
-
-        g_return_if_fail (GFBGRAPH_IS_USER (user));
-        g_return_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer));
-        g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
-        g_return_if_fail (callback != NULL);
-
-        simple_async = g_simple_async_result_new (G_OBJECT (user), callback, user_data, gfbgraph_user_get_albums_async);
-        g_simple_async_result_set_check_cancellable (simple_async, cancellable);
-
-        data = g_slice_new (GFBGraphUserConnectionAsyncData);
-        data->nodes = NULL;
-        data->authorizer = authorizer;
-        g_object_ref (data->authorizer);
-
-        g_simple_async_result_set_op_res_gpointer (simple_async, data, (GDestroyNotify) gfbgraph_user_connection_async_data_free);
-        g_simple_async_result_run_in_thread (simple_async, (GSimpleAsyncThreadFunc) gfbgraph_user_get_albums_async_thread, G_PRIORITY_DEFAULT, cancellable);
-
-        g_object_unref (simple_async);
+  GSimpleAsyncResult *simple_async;
+  GFBGraphUserConnectionAsyncData *data;
+
+  g_return_if_fail (GFBGRAPH_IS_USER (user));
+  g_return_if_fail (GFBGRAPH_IS_AUTHORIZER (authorizer));
+  g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+  g_return_if_fail (callback != NULL);
+
+  simple_async = g_simple_async_result_new (G_OBJECT (user),
+                                            callback,
+                                            user_data,
+                                            gfbgraph_user_get_albums_async);
+  g_simple_async_result_set_check_cancellable (simple_async,
+                                               cancellable);
+
+  data = g_slice_new (GFBGraphUserConnectionAsyncData);
+  data->nodes = NULL;
+  data->authorizer = authorizer;
+  g_object_ref (data->authorizer);
+
+  g_simple_async_result_set_op_res_gpointer (simple_async,
+                                             data,
+                                             (GDestroyNotify)connection_async_data_free);
+  g_simple_async_result_run_in_thread (simple_async,
+                                       (GSimpleAsyncThreadFunc)get_albums_async_thread,
+                                       G_PRIORITY_DEFAULT,
+                                       cancellable);
+
+  g_object_unref (simple_async);
 }
 
 /**
@@ -416,23 +456,27 @@ gfbgraph_user_get_albums_async (GFBGraphUser *user, GFBGraphAuthorizer *authoriz
  *
  * Returns: (element-type GFBGraphAlbum) (transfer full): a newly-allocated #GList of albums owned by the @user.
  **/
-GList*
-gfbgraph_user_get_albums_async_finish (GFBGraphUser *user, GAsyncResult *result, GError **error)
+GList *
+gfbgraph_user_get_albums_async_finish (GFBGraphUser  *user,
+                                       GAsyncResult  *result,
+                                       GError       **error)
 {
-        GSimpleAsyncResult *simple_async;
-        GFBGraphUserConnectionAsyncData *data;
+  GSimpleAsyncResult *simple_async;
+  GFBGraphUserConnectionAsyncData *data;
 
-        g_return_val_if_fail (GFBGRAPH_IS_USER (user), NULL);
-        g_return_val_if_fail (g_simple_async_result_is_valid (result, G_OBJECT (user), gfbgraph_user_get_albums_async), NULL);
-        g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_USER (user), NULL);
+  g_return_val_if_fail (g_simple_async_result_is_valid (result,
+                                                        G_OBJECT (user),
+                                                        gfbgraph_user_get_albums_async), NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
 
-        simple_async = G_SIMPLE_ASYNC_RESULT (result);
+  simple_async = G_SIMPLE_ASYNC_RESULT (result);
 
-        if (g_simple_async_result_propagate_error (simple_async, error))
-                return NULL;
+  if (g_simple_async_result_propagate_error (simple_async, error))
+    return NULL;
 
-        data = (GFBGraphUserConnectionAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
-        return data->nodes;
+  data = (GFBGraphUserConnectionAsyncData *) g_simple_async_result_get_op_res_gpointer (simple_async);
+  return data->nodes;
 }
 
 /**
@@ -443,12 +487,12 @@ gfbgraph_user_get_albums_async_finish (GFBGraphUser *user, GAsyncResult *result,
  *
  * Returns: (transfer none): a const #gchar with the user full name, or %NULL.
  **/
-const gchar*
+const gchar *
 gfbgraph_user_get_name (GFBGraphUser *user)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_USER (user), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_USER (user), NULL);
 
-        return user->priv->name;
+  return user->priv->name;
 }
 
 /**
@@ -460,10 +504,10 @@ gfbgraph_user_get_name (GFBGraphUser *user)
  *
  * Returns: (transfer none): a const #gchar with the user email, or %NULL.
  **/
-const gchar*
+const gchar *
 gfbgraph_user_get_email (GFBGraphUser *user)
 {
-        g_return_val_if_fail (GFBGRAPH_IS_USER (user), NULL);
+  g_return_val_if_fail (GFBGRAPH_IS_USER (user), NULL);
 
-        return user->priv->email;
+  return user->priv->email;
 }
diff --git a/gfbgraph/gfbgraph-user.h b/gfbgraph/gfbgraph-user.h
index 312b1f0..5dd29d5 100644
--- a/gfbgraph/gfbgraph-user.h
+++ b/gfbgraph/gfbgraph-user.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013-2014 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -27,12 +28,17 @@
 
 G_BEGIN_DECLS
 
-#define GFBGRAPH_TYPE_USER             (gfbgraph_user_get_type())
-#define GFBGRAPH_USER(obj)             (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_USER,GFBGraphUser))
-#define GFBGRAPH_USER_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_USER,GFBGraphUserClass))
-#define GFBGRAPH_IS_USER(obj)          (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_USER))
-#define GFBGRAPH_IS_USER_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_USER))
-#define GFBGRAPH_USER_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_USER,GFBGraphUserClass))
+#define GFBGRAPH_TYPE_USER (gfbgraph_user_get_type())
+#define GFBGRAPH_USER(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GFBGRAPH_TYPE_USER,GFBGraphUser))
+#define GFBGRAPH_USER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GFBGRAPH_TYPE_USER,GFBGraphUserClass))
+#define GFBGRAPH_IS_USER(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GFBGRAPH_TYPE_USER))
+#define GFBGRAPH_IS_USER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GFBGRAPH_TYPE_USER))
+#define GFBGRAPH_USER_GET_CLASS(obj) \
+  (G_TYPE_INSTANCE_GET_CLASS((obj),GFBGRAPH_TYPE_USER,GFBGraphUserClass))
 
 typedef struct _GFBGraphUser      GFBGraphUser;
 typedef struct _GFBGraphUserClass GFBGraphUserClass;
@@ -41,27 +47,42 @@ typedef struct _GFBGraphUserPrivate         GFBGraphUserPrivate;
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (GFBGraphUser, g_object_unref)
 
 struct _GFBGraphUser {
-        GFBGraphNode parent;
+  GFBGraphNode parent;
 
-        /*< private >*/
-        GFBGraphUserPrivate *priv;
+  /*< private >*/
+  GFBGraphUserPrivate *priv;
 };
 
 struct _GFBGraphUserClass {
-        GFBGraphNodeClass parent_class;
+  GFBGraphNodeClass parent_class;
 };
 
 GType         gfbgraph_user_get_type  (void) G_GNUC_CONST;
 GFBGraphUser* gfbgraph_user_new       (void);
-GFBGraphUser* gfbgraph_user_new_from_id (GFBGraphAuthorizer *authorizer, const gchar *id, GError **error);
-
-GFBGraphUser* gfbgraph_user_get_me              (GFBGraphAuthorizer *authorizer, GError **error);
-void          gfbgraph_user_get_me_async        (GFBGraphAuthorizer *authorizer, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data);
-GFBGraphUser* gfbgraph_user_get_me_async_finish (GFBGraphAuthorizer *authorizer, GAsyncResult *result, GError **error);
-
-GList*        gfbgraph_user_get_albums              (GFBGraphUser *user, GFBGraphAuthorizer *authorizer, GError **error);
-void          gfbgraph_user_get_albums_async        (GFBGraphUser *user, GFBGraphAuthorizer *authorizer, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data);
-GList*        gfbgraph_user_get_albums_async_finish (GFBGraphUser *user, GAsyncResult *result, GError **error);
+GFBGraphUser* gfbgraph_user_new_from_id (GFBGraphAuthorizer  *authorizer,
+                                         const gchar         *id,
+                                         GError             **error);
+
+GFBGraphUser* gfbgraph_user_get_me              (GFBGraphAuthorizer  *authorizer,
+                                                 GError             **error);
+void          gfbgraph_user_get_me_async        (GFBGraphAuthorizer  *authorizer,
+                                                 GCancellable        *cancellable,
+                                                 GAsyncReadyCallback  callback,
+                                                 gpointer             user_data);
+GFBGraphUser* gfbgraph_user_get_me_async_finish (GFBGraphAuthorizer  *authorizer,
+                                                 GAsyncResult        *result,
+                                                 GError             **error);
+GList*        gfbgraph_user_get_albums              (GFBGraphUser        *user,
+                                                     GFBGraphAuthorizer  *authorizer,
+                                                     GError             **error);
+void          gfbgraph_user_get_albums_async        (GFBGraphUser        *user,
+                                                     GFBGraphAuthorizer  *authorizer,
+                                                     GCancellable        *cancellable,
+                                                     GAsyncReadyCallback  callback,
+                                                     gpointer             user_data);
+GList*        gfbgraph_user_get_albums_async_finish (GFBGraphUser  *user,
+                                                     GAsyncResult  *result,
+                                                     GError       **error);
 
 const gchar*  gfbgraph_user_get_name  (GFBGraphUser *user);
 const gchar*  gfbgraph_user_get_email (GFBGraphUser *user);
diff --git a/gfbgraph/gfbgraph.h b/gfbgraph/gfbgraph.h
index a9f0034..a10fcf1 100644
--- a/gfbgraph/gfbgraph.h
+++ b/gfbgraph/gfbgraph.h
@@ -1,7 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013 Álvaro Peña <alvaropg@gmail.com>
+ *               2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
diff --git a/tests/autoptr.c b/tests/autoptr.c
index 182fc28..b3c37ba 100644
--- a/tests/autoptr.c
+++ b/tests/autoptr.c
@@ -1,7 +1,7 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
- * Copyright (C) 2018 Yi-Soo An <yisooan@gmail.com>
+ * Copyright (C) 2018-2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -28,49 +28,49 @@
 static void
 test_gfbgraph_album (void)
 {
-        g_autoptr (GFBGraphAlbum) val = NULL;
+  g_autoptr (GFBGraphAlbum) val = NULL;
 
-        val = gfbgraph_album_new ();
-        g_assert_nonnull (val);
+  val = gfbgraph_album_new ();
+  g_assert_nonnull (val);
 }
 
 static void
 test_gfbgraph_node (void)
 {
-        g_autoptr (GFBGraphNode) val = NULL;
+  g_autoptr (GFBGraphNode) val = NULL;
 
-        val = gfbgraph_node_new ();
-        g_assert_nonnull (val);
+  val = gfbgraph_node_new ();
+  g_assert_nonnull (val);
 }
 
 static void
 test_gfbgraph_photo (void)
 {
-        g_autoptr (GFBGraphPhoto) val = NULL;
+  g_autoptr (GFBGraphPhoto) val = NULL;
 
-        val = gfbgraph_photo_new ();
-        g_assert_nonnull (val);
+  val = gfbgraph_photo_new ();
+  g_assert_nonnull (val);
 }
 
 static void
 test_gfbgraph_user (void)
 {
-        g_autoptr (GFBGraphUser) val = NULL;
+  g_autoptr (GFBGraphUser) val = NULL;
 
-        val = gfbgraph_user_new ();
-        g_assert_nonnull (val);
+  val = gfbgraph_user_new ();
+  g_assert_nonnull (val);
 }
 
 int
 main (int   argc,
-      char *argv[])
+    char *argv[])
 {
-        g_test_init (&argc, &argv, NULL);
+  g_test_init (&argc, &argv, NULL);
 
-        g_test_add_func ("/GFBGraph/autoptr/Album", test_gfbgraph_album);
-        g_test_add_func ("/GFBGraph/autoptr/Node", test_gfbgraph_node);
-        g_test_add_func ("/GFBGraph/autoptr/Photo", test_gfbgraph_photo);
-        g_test_add_func ("/GFBGraph/autoptr/User", test_gfbgraph_user);
+  g_test_add_func ("/GFBGraph/autoptr/Album", test_gfbgraph_album);
+  g_test_add_func ("/GFBGraph/autoptr/Node", test_gfbgraph_node);
+  g_test_add_func ("/GFBGraph/autoptr/Photo", test_gfbgraph_photo);
+  g_test_add_func ("/GFBGraph/autoptr/User", test_gfbgraph_user);
 
-        return g_test_run ();
+  return g_test_run ();
 }
diff --git a/tests/gtestutils.c b/tests/gtestutils.c
index eef4529..ec3b7bb 100644
--- a/tests/gtestutils.c
+++ b/tests/gtestutils.c
@@ -1,8 +1,8 @@
-/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8; tab-width: 8 -*-  */
+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 2; tab-width: 2 -*-  */
 /*
  * libgfbgraph - GObject library for Facebook Graph API
  * Copyright (C) 2013-2015 Álvaro Peña <alvaropg@gmail.com>
- *                    2019 Leesoo Ahn <yisooan@fedoraproject.org>
+ *               2019-2020 Leesoo Ahn <yisooan@fedoraproject.org>
  *
  * GFBGraph is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -32,17 +32,17 @@ typedef struct _GFBGraphTestApp     GFBGraphTestApp;
 
 struct _GFBGraphTestFixture
 {
-        gchar *user_id;
-        gchar *user_email;
+  gchar *user_id;
+  gchar *user_email;
 
-        GFBGraphSimpleAuthorizer *authorizer;
+  GFBGraphSimpleAuthorizer *authorizer;
 };
 
 struct _GFBGraphTestApp
 {
-        gchar *client_id;
-        gchar *client_secret;
-        gchar *access_token;
+  gchar *client_id;
+  gchar *client_secret;
+  gchar *access_token;
 };
 
 #define FACEBOOK_ENDPOINT "https://graph.facebook.com/v2.10"
@@ -52,231 +52,231 @@ struct _GFBGraphTestApp
 GFBGraphTestApp*
 gfbgraph_test_app_setup (void)
 {
-        GFBGraphTestApp *app;
-        RestProxy *proxy;
-        RestProxyCall *rest_call;
-        g_autofree gchar *function_path = NULL;
-        g_autofree gchar *app_key_filename = NULL;
-        g_autoptr(GError) error = NULL;
-        g_autoptr(GKeyFile) app_key_file = NULL;
-        g_autoptr(JsonParser) jparser = NULL;
-        g_autoptr(JsonReader) jreader = NULL;
-        JsonNode *jnode;
-        const char *payload;
-
-        app_key_filename = g_test_build_filename (G_TEST_BUILT,
-                                                  "credentials.ini",
-                                                  NULL);
-        app_key_file = g_key_file_new ();
-        g_key_file_load_from_file (app_key_file,
-                                   app_key_filename,
-                                   G_KEY_FILE_NONE,
-                                   &error);
-        g_assert_no_error(error);
-
-        app = g_new0(GFBGraphTestApp, 1);
-
-        app->client_id = g_key_file_get_string (app_key_file,
-                                                "Client",
-                                                "ClientId",
-                                                &error);
-        g_assert_no_error(error);
-        app->client_secret = g_key_file_get_string (app_key_file,
-                                                    "Client",
-                                                    "ClientSecret",
-                                                    &error);
-        g_assert_no_error(error);
-
-        proxy = rest_proxy_new (FACEBOOK_ENDPOINT, FALSE);
-        rest_call = rest_proxy_new_call (proxy);
-
-        rest_proxy_call_add_param (rest_call, "client_id", app->client_id);
-        rest_proxy_call_add_param (rest_call, "client_secret", app->client_secret);
-        rest_proxy_call_add_param (rest_call, "grant_type", "client_credentials");
-
-        rest_proxy_call_set_method (rest_call, "GET");
-        function_path = g_strdup ("/oauth/access_token");
-        rest_proxy_call_set_function (rest_call, function_path);
-
-        rest_proxy_call_sync (rest_call, &error);
-        g_assert_no_error (error);
-
-        payload = rest_proxy_call_get_payload (rest_call);
-        jparser = json_parser_new ();
-        json_parser_load_from_data (jparser, payload, -1, &error);
-        g_assert_no_error (error);
-        jnode = json_parser_get_root (jparser);
-        jreader = json_reader_new (jnode);
-        json_reader_read_element (jreader, 0);
-        app->access_token = g_strdup(json_reader_get_string_value (jreader));
-        json_reader_end_element (jreader);
-
-        g_clear_object(&rest_call);
-        g_clear_object(&proxy);
-
-        return app;
+  GFBGraphTestApp *app;
+  RestProxy *proxy;
+  RestProxyCall *rest_call;
+  g_autofree gchar *function_path = NULL;
+  g_autofree gchar *app_key_filename = NULL;
+  g_autoptr(GError) error = NULL;
+  g_autoptr(GKeyFile) app_key_file = NULL;
+  g_autoptr(JsonParser) jparser = NULL;
+  g_autoptr(JsonReader) jreader = NULL;
+  JsonNode *jnode;
+  const char *payload;
+
+  app_key_filename = g_test_build_filename (G_TEST_BUILT,
+      "credentials.ini",
+      NULL);
+  app_key_file = g_key_file_new ();
+  g_key_file_load_from_file (app_key_file,
+      app_key_filename,
+      G_KEY_FILE_NONE,
+      &error);
+  g_assert_no_error(error);
+
+  app = g_new0(GFBGraphTestApp, 1);
+
+  app->client_id = g_key_file_get_string (app_key_file,
+      "Client",
+      "ClientId",
+      &error);
+  g_assert_no_error(error);
+  app->client_secret = g_key_file_get_string (app_key_file,
+      "Client",
+      "ClientSecret",
+      &error);
+  g_assert_no_error(error);
+
+  proxy = rest_proxy_new (FACEBOOK_ENDPOINT, FALSE);
+  rest_call = rest_proxy_new_call (proxy);
+
+  rest_proxy_call_add_param (rest_call, "client_id", app->client_id);
+  rest_proxy_call_add_param (rest_call, "client_secret", app->client_secret);
+  rest_proxy_call_add_param (rest_call, "grant_type", "client_credentials");
+
+  rest_proxy_call_set_method (rest_call, "GET");
+  function_path = g_strdup ("/oauth/access_token");
+  rest_proxy_call_set_function (rest_call, function_path);
+
+  rest_proxy_call_sync (rest_call, &error);
+  g_assert_no_error (error);
+
+  payload = rest_proxy_call_get_payload (rest_call);
+  jparser = json_parser_new ();
+  json_parser_load_from_data (jparser, payload, -1, &error);
+  g_assert_no_error (error);
+  jnode = json_parser_get_root (jparser);
+  jreader = json_reader_new (jnode);
+  json_reader_read_element (jreader, 0);
+  app->access_token = g_strdup(json_reader_get_string_value (jreader));
+  json_reader_end_element (jreader);
+
+  g_clear_object(&rest_call);
+  g_clear_object(&proxy);
+
+  return app;
 }
 
 void
 gfbgraph_test_fixture_setup (GFBGraphTestFixture *fixture, gconstpointer user_data)
 {
-        RestProxy *proxy;
-        RestProxyCall *rest_call;
-        g_autofree gchar *function_path = NULL;
-        const gchar *payload;
-        g_autoptr(GError) error = NULL;
-        const GFBGraphTestApp *app = user_data;
-        JsonNode *jnode;
-        g_autoptr(JsonParser) jparser = NULL;
-        g_autoptr(JsonReader) jreader = NULL;
-        const gchar *access_token;
-
-        /* Create a new user */
-
-        proxy = rest_proxy_new (FACEBOOK_ENDPOINT, FALSE);
-        rest_call = rest_proxy_new_call (proxy);
-
-        /* Params as documented here: https://developers.facebook.com/docs/graph-api/reference/app/accounts/test-users#publish */
-        rest_proxy_call_add_param (rest_call, "installed", "true");
-        rest_proxy_call_add_param (rest_call, "permissions", FACEBOOK_TEST_USER_PERMISSIONS);
-        rest_proxy_call_add_param (rest_call, "access_token", app->access_token);
-
-        rest_proxy_call_set_method (rest_call, "POST");
-        function_path = g_strdup_printf ("%s/accounts/test-users", app->client_id);
-        rest_proxy_call_set_function (rest_call, function_path);
-
-        rest_proxy_call_sync (rest_call, &error);
-        g_assert_no_error (error);
-
-        payload = rest_proxy_call_get_payload (rest_call);
-        jparser = json_parser_new ();
-        json_parser_load_from_data (jparser, payload, -1, &error);
-        g_assert_no_error (error);
-        jnode = json_parser_get_root (jparser);
-        jreader = json_reader_new (jnode);
-
-        json_reader_read_element (jreader, 0);
-        fixture->user_id = g_strdup (json_reader_get_string_value (jreader));
-        json_reader_end_element (jreader);
-        json_reader_read_element (jreader, 1);
-        access_token = json_reader_get_string_value (jreader);
-        json_reader_end_element (jreader);
-        json_reader_read_element (jreader, 3);
-        fixture->user_email = g_strdup (json_reader_get_string_value (jreader));
-        json_reader_end_element (jreader);
-
-        fixture->authorizer = gfbgraph_simple_authorizer_new (access_token);
-
-        g_clear_object (&rest_call);
-        g_clear_object (&proxy);
+  RestProxy *proxy;
+  RestProxyCall *rest_call;
+  g_autofree gchar *function_path = NULL;
+  const gchar *payload;
+  g_autoptr(GError) error = NULL;
+  const GFBGraphTestApp *app = user_data;
+  JsonNode *jnode;
+  g_autoptr(JsonParser) jparser = NULL;
+  g_autoptr(JsonReader) jreader = NULL;
+  const gchar *access_token;
+
+  /* Create a new user */
+
+  proxy = rest_proxy_new (FACEBOOK_ENDPOINT, FALSE);
+  rest_call = rest_proxy_new_call (proxy);
+
+  /* Params as documented here: https://developers.facebook.com/docs/graph-api/reference/app/accounts/test-users#publish */
+  rest_proxy_call_add_param (rest_call, "installed", "true");
+  rest_proxy_call_add_param (rest_call, "permissions", FACEBOOK_TEST_USER_PERMISSIONS);
+  rest_proxy_call_add_param (rest_call, "access_token", app->access_token);
+
+  rest_proxy_call_set_method (rest_call, "POST");
+  function_path = g_strdup_printf ("%s/accounts/test-users", app->client_id);
+  rest_proxy_call_set_function (rest_call, function_path);
+
+  rest_proxy_call_sync (rest_call, &error);
+  g_assert_no_error (error);
+
+  payload = rest_proxy_call_get_payload (rest_call);
+  jparser = json_parser_new ();
+  json_parser_load_from_data (jparser, payload, -1, &error);
+  g_assert_no_error (error);
+  jnode = json_parser_get_root (jparser);
+  jreader = json_reader_new (jnode);
+
+  json_reader_read_element (jreader, 0);
+  fixture->user_id = g_strdup (json_reader_get_string_value (jreader));
+  json_reader_end_element (jreader);
+  json_reader_read_element (jreader, 1);
+  access_token = json_reader_get_string_value (jreader);
+  json_reader_end_element (jreader);
+  json_reader_read_element (jreader, 3);
+  fixture->user_email = g_strdup (json_reader_get_string_value (jreader));
+  json_reader_end_element (jreader);
+
+  fixture->authorizer = gfbgraph_simple_authorizer_new (access_token);
+
+  g_clear_object (&rest_call);
+  g_clear_object (&proxy);
 
 }
 
 static void
 gfbgraph_test_fixture_teardown (GFBGraphTestFixture *fixture, G_GNUC_UNUSED gconstpointer user_data)
 {
-        g_autoptr(SoupSession) ssession = NULL;
-        g_autoptr(SoupMessage) smessage = NULL;
-        g_autofree gchar *function_path = NULL;
-        guint status;
+  g_autoptr(SoupSession) ssession = NULL;
+  g_autoptr(SoupMessage) smessage = NULL;
+  g_autofree gchar *function_path = NULL;
+  guint status;
 
-        /* Delete the test user and clean up memory */
+  /* Delete the test user and clean up memory */
 
-        ssession = soup_session_new ();
+  ssession = soup_session_new ();
 
-        function_path = g_strdup_printf ("%s/%s", FACEBOOK_ENDPOINT, fixture->user_id);
-        smessage = soup_message_new ("DELETE", function_path);
-        gfbgraph_authorizer_process_message (GFBGRAPH_AUTHORIZER (fixture->authorizer), smessage);
+  function_path = g_strdup_printf ("%s/%s", FACEBOOK_ENDPOINT, fixture->user_id);
+  smessage = soup_message_new ("DELETE", function_path);
+  gfbgraph_authorizer_process_message (GFBGRAPH_AUTHORIZER (fixture->authorizer), smessage);
 
-        status = soup_session_send_message (ssession, smessage);
-        g_assert_cmpint(status, ==, 200);
+  status = soup_session_send_message (ssession, smessage);
+  g_assert_cmpint(status, ==, 200);
 
-        g_free (fixture->user_id);
-        g_free (fixture->user_email);
-        g_object_unref (fixture->authorizer);
+  g_free (fixture->user_id);
+  g_free (fixture->user_email);
+  g_object_unref (fixture->authorizer);
 }
 
 static void
 gfbgraph_test_me (GFBGraphTestFixture *fixture, G_GNUC_UNUSED gconstpointer user_data)
 {
-        g_autoptr(GFBGraphUser) me = NULL;
-        g_autoptr(GError) error = NULL;
+  g_autoptr(GFBGraphUser) me = NULL;
+  g_autoptr(GError) error = NULL;
 
-        me = gfbgraph_user_get_me (GFBGRAPH_AUTHORIZER (fixture->authorizer), &error);
-        g_assert_no_error (error);
-        g_assert (GFBGRAPH_IS_USER (me));
+  me = gfbgraph_user_get_me (GFBGRAPH_AUTHORIZER (fixture->authorizer), &error);
+  g_assert_no_error (error);
+  g_assert (GFBGRAPH_IS_USER (me));
 
-        g_assert_cmpstr (fixture->user_id, ==, gfbgraph_node_get_id (GFBGRAPH_NODE (me)));
-        g_assert_cmpstr (fixture->user_email, ==, gfbgraph_user_get_email (me));
+  g_assert_cmpstr (fixture->user_id, ==, gfbgraph_node_get_id (GFBGRAPH_NODE (me)));
+  g_assert_cmpstr (fixture->user_email, ==, gfbgraph_user_get_email (me));
 }
 
 static G_GNUC_UNUSED void
 gfbgraph_test_album (GFBGraphTestFixture *fixture, G_GNUC_UNUSED gconstpointer user_data)
 {
-        GFBGraphUser *me;
-        GFBGraphAlbum *album;
-        GError *error = NULL;
-        gboolean result;
-
-        me = gfbgraph_user_get_me (GFBGRAPH_AUTHORIZER (fixture->authorizer), &error);
-        g_assert_no_error (error);
-        g_assert (GFBGRAPH_IS_USER (me));
-
-        /* Create a photo album */
-        album = gfbgraph_album_new ();
-        gfbgraph_album_set_name (album, "Vanilla Sky");
-        gfbgraph_album_set_description (album, "Great sunset photos in Mars!");
-        result = gfbgraph_node_append_connection (GFBGRAPH_NODE (me),
-                                                  GFBGRAPH_NODE (album),
-                                                  GFBGRAPH_AUTHORIZER (fixture->authorizer),
-                                                  &error);
-        /* Asserting the connection */
-        g_assert_no_error (error);
-        g_assert (result);
-
-        /* Asserting the Album ID */
-        g_assert_cmpstr (gfbgraph_node_get_id (GFBGRAPH_NODE (album)), !=, "");
+  GFBGraphUser *me;
+  GFBGraphAlbum *album;
+  GError *error = NULL;
+  gboolean result;
+
+  me = gfbgraph_user_get_me (GFBGRAPH_AUTHORIZER (fixture->authorizer), &error);
+  g_assert_no_error (error);
+  g_assert (GFBGRAPH_IS_USER (me));
+
+  /* Create a photo album */
+  album = gfbgraph_album_new ();
+  gfbgraph_album_set_name (album, "Vanilla Sky");
+  gfbgraph_album_set_description (album, "Great sunset photos in Mars!");
+  result = gfbgraph_node_append_connection (GFBGRAPH_NODE (me),
+      GFBGRAPH_NODE (album),
+      GFBGRAPH_AUTHORIZER (fixture->authorizer),
+      &error);
+  /* Asserting the connection */
+  g_assert_no_error (error);
+  g_assert (result);
+
+  /* Asserting the Album ID */
+  g_assert_cmpstr (gfbgraph_node_get_id (GFBGRAPH_NODE (album)), !=, "");
 }
 
 int
 main (int argc, char **argv)
 {
-        GFBGraphTestApp *app = NULL;
-        int test_result;
+  GFBGraphTestApp *app = NULL;
+  int test_result;
 
-        g_test_init (&argc, &argv, NULL);
+  g_test_init (&argc, &argv, NULL);
 
-        g_log_set_always_fatal (G_LOG_LEVEL_ERROR | G_LOG_FLAG_RECURSION | G_LOG_FLAG_FATAL | G_LOG_LEVEL_CRITICAL);
+  g_log_set_always_fatal (G_LOG_LEVEL_ERROR | G_LOG_FLAG_RECURSION | G_LOG_FLAG_FATAL | G_LOG_LEVEL_CRITICAL);
 
-        app = gfbgraph_test_app_setup ();
+  app = gfbgraph_test_app_setup ();
 
-        g_test_add ("/GFBGraph/Me",
-                    GFBGraphTestFixture,
-                    app,
-                    gfbgraph_test_fixture_setup,
-                    gfbgraph_test_me,
-                    gfbgraph_test_fixture_teardown);
+  g_test_add ("/GFBGraph/Me",
+      GFBGraphTestFixture,
+      app,
+      gfbgraph_test_fixture_setup,
+      gfbgraph_test_me,
+      gfbgraph_test_fixture_teardown);
 
 #if 0
-        g_test_add ("/GFBGraph/Album",
-                    GFBGraphTestFixture,
-                    app,
-                    gfbgraph_test_fixture_setup,
-                    gfbgraph_test_album,
-                    gfbgraph_test_fixture_teardown);
+  g_test_add ("/GFBGraph/Album",
+      GFBGraphTestFixture,
+      app,
+      gfbgraph_test_fixture_setup,
+      gfbgraph_test_album,
+      gfbgraph_test_fixture_teardown);
 #endif
 
-        test_result = g_test_run ();
+  test_result = g_test_run ();
 
-        if (app) {
-                if (app->client_id)
-                        g_free (app->client_id);
-                if (app->client_secret)
-                        g_free (app->client_secret);
-                if (app->access_token)
-                        g_free (app->access_token);
-                g_free (app);
-        }
+  if (app) {
+    if (app->client_id)
+      g_free (app->client_id);
+    if (app->client_secret)
+      g_free (app->client_secret);
+    if (app->access_token)
+      g_free (app->access_token);
+    g_free (app);
+  }
 
-        return test_result;
+  return test_result;
 }