youtube: Add a GDataYouTubeFeed helper class for parsing feeds

This parses YouTube-specific properties of the feed — specifically, the
total-results and items-per-page, which were previously handled in a
service-agnostic manner by GDataFeed, but YouTube doesn’t conform to
that.

This adds the following new API:
 • GDataYouTubeFeed

8 files changed, 201 insertions, 1 deletions

diff --git a/Makefile.am b/Makefile.am
index 964ac4b6..1e1e0096 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -321,7 +321,8 @@ gdata_youtube_headers = \
 	gdata/services/youtube/gdata-youtube-query.h	\
 	gdata/services/youtube/gdata-youtube-state.h	\
 	gdata/services/youtube/gdata-youtube-category.h	\
-	gdata/services/youtube/gdata-youtube-comment.h
+	gdata/services/youtube/gdata-youtube-comment.h	\
+	gdata/services/youtube/gdata-youtube-feed.h
 private_headers += \
 	gdata/services/youtube/gdata-youtube-group.h	\
 	gdata/services/youtube/gdata-youtube-control.h
@@ -453,6 +454,7 @@ gdata_sources = \
 	gdata/services/youtube/gdata-youtube-control.c		\
 	gdata/services/youtube/gdata-youtube-category.c		\
 	gdata/services/youtube/gdata-youtube-comment.c		\
+	gdata/services/youtube/gdata-youtube-feed.c		\
 	\
 	gdata/services/tasks/gdata-tasks-service.c			\
 	gdata/services/tasks/gdata-tasks-tasklist.c			\
diff --git a/docs/reference/gdata-docs.xml b/docs/reference/gdata-docs.xml
index 2e4e0771..5233faa1 100644
--- a/docs/reference/gdata-docs.xml
+++ b/docs/reference/gdata-docs.xml
@@ -128,6 +128,7 @@
 		<chapter>
 			<title>YouTube API</title>
 			<xi:include href="xml/gdata-youtube-service.xml"/>
+			<xi:include href="xml/gdata-youtube-feed.xml"/>
 			<xi:include href="xml/gdata-youtube-query.xml"/>
 			<xi:include href="xml/gdata-youtube-video.xml"/>
 			<xi:include href="xml/gdata-youtube-comment.xml"/>
diff --git a/docs/reference/gdata-sections.txt b/docs/reference/gdata-sections.txt
index 0c109c21..22f78693 100644
--- a/docs/reference/gdata-sections.txt
+++ b/docs/reference/gdata-sections.txt
@@ -2795,3 +2795,20 @@ gdata_oauth2_authorizer_get_type
 <SUBSECTION Private>
 GDataOAuth2AuthorizerPrivate
 </SECTION>
+
+<SECTION>
+<FILE>gdata-youtube-feed</FILE>
+<TITLE>GDataYouTubeFeed</TITLE>
+GDataYouTubeFeed
+GDataYouTubeFeedClass
+<SUBSECTION Standard>
+gdata_youtube_feed_get_type
+GDATA_YOUTUBE_FEED
+GDATA_YOUTUBE_FEED_CLASS
+GDATA_YOUTUBE_FEED_GET_CLASS
+GDATA_IS_YOUTUBE_FEED
+GDATA_IS_YOUTUBE_FEED_CLASS
+GDATA_TYPE_YOUTUBE_FEED
+<SUBSECTION Private>
+GDataYouTubeFeedPrivate
+</SECTION>
diff --git a/gdata/gdata.h b/gdata/gdata.h
index fe7a4c3a..e74dd06c 100644
--- a/gdata/gdata.h
+++ b/gdata/gdata.h
@@ -91,6 +91,7 @@
 
 /* YouTube */
 #include <gdata/services/youtube/gdata-youtube-service.h>
+#include <gdata/services/youtube/gdata-youtube-feed.h>
 #include <gdata/services/youtube/gdata-youtube-query.h>
 #include <gdata/services/youtube/gdata-youtube-video.h>
 #include <gdata/services/youtube/gdata-youtube-content.h>
diff --git a/gdata/gdata.symbols b/gdata/gdata.symbols
index 7ae3e955..830f0bf3 100644
--- a/gdata/gdata.symbols
+++ b/gdata/gdata.symbols
@@ -95,6 +95,7 @@ gdata_query_set_max_results
 gdata_query_get_etag
 gdata_query_set_etag
 gdata_youtube_standard_feed_type_get_type
+gdata_youtube_feed_get_type
 gdata_youtube_service_error_get_type
 gdata_youtube_service_error_quark
 gdata_youtube_service_get_type
diff --git a/gdata/services/youtube/gdata-youtube-feed.c b/gdata/services/youtube/gdata-youtube-feed.c
new file mode 100644
index 00000000..469c5ae4
--- /dev/null
+++ b/gdata/services/youtube/gdata-youtube-feed.c
@@ -0,0 +1,102 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
+/*
+ * GData Client
+ * Copyright (C) Philip Withnall 2015 <philip@tecnocode.co.uk>
+ *
+ * GData Client is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * GData Client is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GData Client.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * SECTION:gdata-youtube-feed
+ * @short_description: GData YouTube feed object
+ * @stability: Stable
+ * @include: gdata/services/youtube/gdata-youtube-feed.h
+ *
+ * #GDataYouTubeFeed is a list of entries (#GDataYouTubeVideo subclasses)
+ * returned as the result of a query to a #GDataYouTubeService, or given as the
+ * input to another operation on the online service.
+ *
+ * Each #GDataYouTubeVideo represents a single video on YouTube, and the
+ * #GDataYouTubeFeed represents a collection of those objects.
+ *
+ * Since: UNRELEASED
+ */
+
+#include <config.h>
+#include <glib.h>
+#include <glib/gi18n-lib.h>
+#include <string.h>
+
+#include "gdata-youtube-feed.h"
+#include "gdata-youtube-video.h"
+#include "gdata-types.h"
+#include "gdata-private.h"
+#include "gdata-service.h"
+
+static gboolean
+parse_json (GDataParsable *parsable, JsonReader *reader, gpointer user_data,
+            GError **error);
+
+G_DEFINE_TYPE (GDataYouTubeFeed, gdata_youtube_feed, GDATA_TYPE_FEED)
+
+static void
+gdata_youtube_feed_class_init (GDataYouTubeFeedClass *klass)
+{
+	GDataParsableClass *parsable_class = GDATA_PARSABLE_CLASS (klass);
+	parsable_class->parse_json = parse_json;
+}
+
+static void
+gdata_youtube_feed_init (GDataYouTubeFeed *self)
+{
+	/* Move along now. */
+}
+
+static gboolean
+parse_json (GDataParsable *parsable, JsonReader *reader, gpointer user_data,
+            GError **error)
+{
+	if (g_strcmp0 (json_reader_get_member_name (reader), "pageInfo") == 0) {
+		guint total_results, items_per_page;
+		const GError *child_error = NULL;
+
+		/* Check this is an object. */
+		if (!json_reader_is_object (reader)) {
+			return gdata_parser_error_required_json_content_missing (reader, error);
+		}
+
+		/* https://developers.google.com/youtube/v3/docs/playlists/list/ */
+		json_reader_read_member (reader, "totalResults");
+		total_results = json_reader_get_int_value (reader);
+		json_reader_end_member (reader);
+
+		json_reader_read_member (reader, "resultsPerPage");
+		items_per_page = json_reader_get_int_value (reader);
+		json_reader_end_member (reader);
+
+		child_error = json_reader_get_error (reader);
+		if (child_error != NULL) {
+			return gdata_parser_error_from_json_error (reader,
+			                                           child_error,
+			                                           error);
+		}
+
+		_gdata_feed_set_page_info (GDATA_FEED (parsable), total_results,
+		                           items_per_page);
+
+		return TRUE;
+	} else {
+		return GDATA_PARSABLE_CLASS (gdata_youtube_feed_parent_class)->parse_json (parsable, reader, user_data, error);
+	}
+}
diff --git a/gdata/services/youtube/gdata-youtube-feed.h b/gdata/services/youtube/gdata-youtube-feed.h
new file mode 100644
index 00000000..0ab173b8
--- /dev/null
+++ b/gdata/services/youtube/gdata-youtube-feed.h
@@ -0,0 +1,74 @@
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
+/*
+ * GData Client
+ * Copyright (C) Philip Withnall 2015 <philip@tecnocode.co.uk>
+ *
+ * GData Client is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * GData Client is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GData Client.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef GDATA_YOUTUBE_FEED_H
+#define GDATA_YOUTUBE_FEED_H
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gdata/gdata-feed.h>
+
+G_BEGIN_DECLS
+
+#define GDATA_TYPE_YOUTUBE_FEED		(gdata_youtube_feed_get_type ())
+#define GDATA_YOUTUBE_FEED(o)		(G_TYPE_CHECK_INSTANCE_CAST ((o), GDATA_TYPE_YOUTUBE_FEED, GDataYouTubeFeed))
+#define GDATA_YOUTUBE_FEED_CLASS(k)	(G_TYPE_CHECK_CLASS_CAST((k), GDATA_TYPE_YOUTUBE_FEED, GDataYouTubeFeedClass))
+#define GDATA_IS_YOUTUBE_FEED(o)	(G_TYPE_CHECK_INSTANCE_TYPE ((o), GDATA_TYPE_YOUTUBE_FEED))
+#define GDATA_IS_YOUTUBE_FEED_CLASS(k)	(G_TYPE_CHECK_CLASS_TYPE ((k), GDATA_TYPE_YOUTUBE_FEED))
+#define GDATA_YOUTUBE_FEED_GET_CLASS(o)	(G_TYPE_INSTANCE_GET_CLASS ((o), GDATA_TYPE_YOUTUBE_FEED, GDataYouTubeFeedClass))
+
+typedef struct _GDataYouTubeFeedPrivate	GDataYouTubeFeedPrivate;
+
+/**
+ * GDataYouTubeFeed:
+ *
+ * All the fields in the #GDataYouTubeFeed structure are private and should
+ * never be accessed directly.
+ *
+ * Since: UNRELEASED
+ */
+typedef struct {
+	/*< private >*/
+	GDataFeed parent;
+	GDataYouTubeFeedPrivate *priv;
+} GDataYouTubeFeed;
+
+/**
+ * GDataYouTubeFeedClass:
+ *
+ * All the fields in the #GDataYouTubeFeedClass structure are private and should
+ * never be accessed directly.
+ *
+ * Since: UNRELEASED
+ */
+typedef struct {
+	/*< private >*/
+	GDataFeedClass parent;
+
+	/*< private >*/
+	/* Padding for future expansion */
+	void (*_g_reserved0) (void);
+	void (*_g_reserved1) (void);
+} GDataYouTubeFeedClass;
+
+GType gdata_youtube_feed_get_type (void) G_GNUC_CONST;
+
+G_END_DECLS
+
+#endif /* !GDATA_YOUTUBE_FEED_H */
diff --git a/gdata/services/youtube/gdata-youtube-service.c b/gdata/services/youtube/gdata-youtube-service.c
index e1210ae4..7e54fafa 100644
--- a/gdata/services/youtube/gdata-youtube-service.c
+++ b/gdata/services/youtube/gdata-youtube-service.c
@@ -244,6 +244,7 @@
 #include <string.h>
 
 #include "gdata-youtube-service.h"
+#include "gdata-youtube-feed.h"
 #include "gdata-service.h"
 #include "gdata-private.h"
 #include "gdata-parser.h"
@@ -292,6 +293,7 @@ gdata_youtube_service_class_init (GDataYouTubeServiceClass *klass)
 	gobject_class->get_property = gdata_youtube_service_get_property;
 	gobject_class->finalize = gdata_youtube_service_finalize;
 
+	service_class->feed_type = GDATA_TYPE_YOUTUBE_FEED;
 	service_class->append_query_headers = append_query_headers;
 	service_class->parse_error_response = parse_error_response;
 	service_class->get_authorization_domains = get_authorization_domains;