backends: Add initial tracker backendtintou/tracker

10 files changed, 1152 insertions, 1 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index e4f56b1e..94474d04 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -28,7 +28,7 @@ build-folks:
       dbus-glib-devel evolution-data-server-devel glib2-devel
       gobject-introspection-devel libgee-devel libxml2-devel meson ninja-build
       python3-dbusmock readline-devel redhat-rpm-config telepathy-glib-devel
-      telepathy-glib-vala vala valadoc gtk-doc
+      telepathy-glib-vala tracker-devel vala valadoc gtk-doc
       dbus-daemon # FIXME: dbus-broker breaks the CI, see https://github.com/bus1/dbus-broker/issues/145
   script:
     - meson _build -Ddocs=true
diff --git a/backends/meson.build b/backends/meson.build
index f3557257..621390f8 100644
--- a/backends/meson.build
+++ b/backends/meson.build
@@ -38,3 +38,7 @@ endif
 if bluez_backend_enabled
   subdir('bluez')
 endif
+
+if tracker_backend_enabled
+  subdir('tracker')
+endif
diff --git a/backends/tracker/meson.build b/backends/tracker/meson.build
new file mode 100644
index 00000000..a271fa55
--- /dev/null
+++ b/backends/tracker/meson.build
@@ -0,0 +1,42 @@
+tracker_backend_name = 'tracker'
+
+# NOTE: we don't export a backend library here.
+
+tracker_backend_sources = [
+  'tracker-backend-factory.vala',
+  'tracker-backend.vala',
+  'tracker-persona-store.vala',
+  'tracker-persona.vala',
+]
+
+tracker_backend_deps = [
+  backend_deps,
+  tracker_dep,
+  libm_dep,
+]
+
+tracker_backend_vala_flags = [
+]
+
+tracker_backend_c_flags = [
+  '-include', 'config.h',
+  '-DBACKEND_NAME="@0@"'.format(tracker_backend_name),
+  '-DG_LOG_DOMAIN="@0@"'.format(tracker_backend_name),
+]
+
+tracker_backend = shared_library(tracker_backend_name,
+  tracker_backend_sources,
+  dependencies: tracker_backend_deps,
+  vala_args: tracker_backend_vala_flags,
+  c_args: tracker_backend_c_flags,
+  name_prefix: '',
+  install_dir: folks_backend_dir / tracker_backend_name,
+  install: true,
+)
+
+tracker_backend_dep = declare_dependency(
+  link_with: tracker_backend,
+  include_directories: include_directories('.'),
+)
+
+folks_backends += tracker_backend
diff --git a/backends/tracker/tracker-backend-factory.vala b/backends/tracker/tracker-backend-factory.vala
new file mode 100644
index 00000000..fd30995f
--- /dev/null
+++ b/backends/tracker/tracker-backend-factory.vala
@@ -0,0 +1,41 @@
+/*
+ * Copyright 2023 Collabora Ltd.
+ *
+ * This library 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.
+ *
+ * This library 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 this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *       Corentin Noël <corentin.noel@collabora.com>
+ */
+
+using Folks;
+
+/**
+ * The backend module entry point.
+ *
+ * @backend_store a store to add the Tracker backends to
+ */
+public void module_init (BackendStore backend_store)
+{
+  backend_store.add_backend (new Folks.Backends.TrackerBackend ());
+}
+
+/**
+ * The backend module exit point.
+ *
+ * @param backend_store the store to remove the backends from
+ */
+public void module_finalize (BackendStore backend_store)
+{
+  /* FIXME: No way to remove backends from the store. */
+}
diff --git a/backends/tracker/tracker-backend.vala b/backends/tracker/tracker-backend.vala
new file mode 100644
index 00000000..ced51ccb
--- /dev/null
+++ b/backends/tracker/tracker-backend.vala
@@ -0,0 +1,207 @@
+/*
+ * Copyright 2023 Collabora Ltd.
+ *
+ * This library 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.
+ *
+ * This library 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 this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *       Corentin Noël <corentin.noel@collabora.com>
+ */
+
+using GLib;
+using Gee;
+using Folks;
+
+extern const string BACKEND_NAME;
+
+/**
+ * A backend which loads {@link Persona}s from paired Bluetooth
+ * devices using the Phonebook Access Protocol (PBAP) and presents them
+ * using one {@link PersonaStore} per device.
+ */
+public class Folks.Backends.TrackerBackend : Folks.Backend
+{
+  private bool _is_prepared = false;
+  private bool _prepare_pending = false; /* used for unprepare() too */
+  private bool _is_quiescent = false;
+  /* Map from PersonaStore.id to PersonaStore. */
+  private HashMap<string, PersonaStore> _persona_stores;
+  private Map<string, PersonaStore> _persona_stores_ro;
+  private Tracker.Sparql.Connection sparql_connection;
+
+  /**
+   * Whether this Backend has been prepared.
+   *
+   * See {@link Folks.Backend.is_prepared}.
+   *
+   * @since 0.9.6
+   */
+  public override bool is_prepared
+    {
+      get { return this._is_prepared; }
+    }
+
+  /**
+   * Whether this Backend has reached a quiescent state.
+   *
+   * See {@link Folks.Backend.is_quiescent}.
+   *
+   * @since 0.9.6
+   */
+  public override bool is_quiescent
+    {
+      get { return this._is_quiescent; }
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override string name { get { return BACKEND_NAME; } }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override Map<string, Folks.PersonaStore> persona_stores
+    {
+      get { return this._persona_stores_ro; }
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override void disable_persona_store (Folks.PersonaStore store)
+    {
+        //TODO
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override void enable_persona_store (Folks.PersonaStore store)
+    {
+      // TODO
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override void set_persona_stores (Set<string>? storeids)
+    {
+      //TODO
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public TrackerBackend ()
+    {
+      Object ();
+    }
+
+  construct
+    {
+      this._persona_stores = new HashMap<string, PersonaStore> ();
+      this._persona_stores_ro = this._persona_stores.read_only_view;
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override async void prepare () throws DBusError
+    {
+      var profiling = Internal.profiling_start ("preparing Tracker.Backend");
+
+      if (this._is_prepared || this._prepare_pending)
+        {
+          return;
+        }
+
+      _prepare_pending = true;
+      this.freeze_notify ();
+
+      Cancellable? cancellable = null;
+      try {
+          sparql_connection = yield Tracker.Sparql.Connection.bus_new_async ("org.freedesktop.Tracker3.Miner.EDS", null, null, cancellable);
+          var cursor = yield sparql_connection.query_async (
+            """SELECT ?addressbook ?addressbookName WHERE { ?addressbook a nco:ContactList  .
+                OPTIONAL {
+                    ?addressbook nie:title ?addressbookName .
+                } }""", cancellable);
+          while (yield cursor.next_async (cancellable)) {
+            long length;
+            unowned var addressbook_urn = cursor.get_string (0, out length);
+            unowned var title = cursor.get_string (1, out length);
+            var store = new TrackerPersonaStore (sparql_connection, addressbook_urn, title);
+            _persona_stores.set (store.id, store);
+          }
+      } catch (Error e) {
+        critical (e.message);
+      }
+
+      this._is_prepared = true;
+      this.notify_property ("is-prepared");
+
+      this._is_quiescent = true;
+      this.notify_property ("is-quiescent");
+
+      this.thaw_notify ();
+      this._prepare_pending = false;
+
+      Internal.profiling_end ((owned) profiling);
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override async void unprepare () throws GLib.Error
+    {
+      if (!this._is_prepared || this._prepare_pending == true)
+        {
+          return;
+        }
+
+      this._prepare_pending = true;
+
+      this.freeze_notify ();
+
+      //TODO
+
+      this.notify_property ("persona-stores");
+
+      this._is_quiescent = false;
+      this.notify_property ("is-quiescent");
+
+      this._is_prepared = false;
+      this.notify_property ("is-prepared");
+
+      this.thaw_notify ();
+      this._prepare_pending = false;
+    }
+}
+
diff --git a/backends/tracker/tracker-persona-store.vala b/backends/tracker/tracker-persona-store.vala
new file mode 100644
index 00000000..c42e8e8a
--- /dev/null
+++ b/backends/tracker/tracker-persona-store.vala
@@ -0,0 +1,271 @@
+/*
+ * Copyright 2023 Collabora Ltd.
+ *
+ * This library 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.
+ *
+ * This library 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 this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *       Corentin Noël <corentin.noel@collabora.com>
+ */
+
+using GLib;
+using Gee;
+using Folks;
+
+/**
+ * A persona store which is associated with a single BlueZ PBAP server (i.e.
+ * one {@link PersonaStore} per device). It will create a {@link Persona} for
+ * each contact on the device.
+ *
+ * Since large contact lists can take a long time to download in full (on the
+ * order of 1s per 10 contacts), contacts are downloaded in two phases:
+ * # Phase 1 downloads all non-PHOTO data. This is very fast (on the order of
+ * 1s per 400 contacts)
+ * # Phase 2 downloads all PHOTO data for those contacts. This is slow, but
+ * happens later, in the background.
+ *
+ * Subsequent download attempts happen on an exponentially increasing interval,
+ * up to a limit (once this limit is reached, updates occur on a regular
+ * interval; the linear region). Download attempts repeat indefinitely unless a
+ * certain number of consecutive attempts end in failure. See the documentation
+ * for {@link _schedule_update_contacts} for details.
+ *
+ * @since 0.9.6
+ */
+public class Folks.Backends.TrackerPersonaStore : Folks.PersonaStore
+{
+  private HashMap<string, TrackerPersona> _personas;
+  private Map<string, TrackerPersona> _personas_ro;
+  private bool _is_prepared = false;
+  private bool _prepare_pending = false;
+  private bool _is_quiescent = false;
+  private Tracker.Sparql.Connection sparql_connection;
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override string type_id { get { return BACKEND_NAME; } }
+
+  /**
+   * Whether this PersonaStore can add {@link Folks.Persona}s.
+   *
+   * See {@link Folks.PersonaStore.can_add_personas}.
+   *
+   * @since 0.9.6
+   */
+  public override MaybeBool can_add_personas
+    {
+      get { return MaybeBool.FALSE; }
+    }
+
+  /**
+   * Whether this PersonaStore can set the alias of {@link Folks.Persona}s.
+   *
+   * See {@link Folks.PersonaStore.can_alias_personas}.
+   *
+   * @since 0.9.6
+   */
+  public override MaybeBool can_alias_personas
+    {
+      get { return MaybeBool.FALSE; }
+    }
+
+  /**
+   * Whether this PersonaStore can set the groups of {@link Folks.Persona}s.
+   *
+   * See {@link Folks.PersonaStore.can_group_personas}.
+   *
+   * @since 0.9.6
+   */
+  public override MaybeBool can_group_personas
+    {
+      get { return MaybeBool.FALSE; }
+    }
+
+  /**
+   * Whether this PersonaStore can remove {@link Folks.Persona}s.
+   *
+   * See {@link Folks.PersonaStore.can_remove_personas}.
+   *
+   * @since 0.9.6
+   */
+  public override MaybeBool can_remove_personas
+    {
+      get { return MaybeBool.FALSE; }
+    }
+
+  /**
+   * Whether this PersonaStore has been prepared.
+   *
+   * See {@link Folks.PersonaStore.is_prepared}.
+   *
+   * @since 0.9.6
+   */
+  public override bool is_prepared
+    {
+      get { return this._is_prepared; }
+    }
+
+  /**
+   * Whether this PersonaStore has reached a quiescent state.
+   *
+   * See {@link Folks.PersonaStore.is_quiescent}.
+   *
+   * @since 0.9.6
+   */
+  public override bool is_quiescent
+    {
+      get { return this._is_quiescent; }
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  private class string[] _always_writeable_properties = {};
+  public override string[] always_writeable_properties
+    {
+      get { return this._always_writeable_properties; }
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override Map<string, Folks.Persona> personas
+    {
+      get { return this._personas_ro; }
+    }
+
+  /**
+   * Create a new PersonaStore.
+   *
+   * Create a new persona store to expose the {@link Persona}s provided by the
+   * addressbook with the given urn.
+   *
+   * @param sparql_connection the Sparql connection
+   * @param addressbook_urn the URN of the addressbook
+   *
+   * @since 0.9.6
+   */
+  public TrackerPersonaStore (Tracker.Sparql.Connection sparql_connection, string addressbook_urn, string? title)
+    {
+      Object (id: addressbook_urn, display_name: title);
+      this.sparql_connection = sparql_connection;
+    }
+
+  construct
+    {
+      this._personas = new HashMap<string, TrackerPersona> ();
+      this._personas_ro = this._personas.read_only_view;
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override async void prepare () throws PersonaStoreError
+    {
+      var profiling = Internal.profiling_start ("preparing Tracker.PersonaStore (ID: %s)",
+          this.id);
+
+      if (this._is_prepared || this._prepare_pending)
+        {
+          return;
+        }
+
+      try
+        {
+          this._prepare_pending = true;
+
+          var added_personas = new HashSet<Persona> ();
+          var cursor = yield sparql_connection.query_async (
+            """SELECT ?contact ?contactUID ?contactFullname {
+                <%s> nco:containsContact ?contact .
+                ?contact nco:contactUID ?contactUID .
+                ?contact nco:fullname ?contactFullname
+            }""".printf (id), null);
+          while (yield cursor.next_async (null)) {
+            long length;
+            unowned var contact_urn = cursor.get_string (0, out length);
+            unowned var contact_uid = cursor.get_string (1, out length);
+            unowned var contact_fullname = cursor.get_string (2, out length);
+            var persona = new TrackerPersona (sparql_connection, this, contact_urn, contact_uid, contact_fullname);
+            _personas.set (persona.iid, persona);
+            added_personas.add (persona);
+          }
+
+        if (added_personas.is_empty == false)
+        {
+          this._emit_personas_changed (added_personas, null);
+        }
+
+          this._is_prepared = true;
+          this.notify_property ("is-prepared");
+
+          this._is_quiescent = true;
+          this.notify_property ("is-quiescent");
+        }
+      catch (Error e)
+        {
+          critical (e.message);
+        }
+      finally
+        {
+          this._prepare_pending = false;
+        }
+
+      Internal.profiling_end ((owned) profiling);
+    }
+
+  /**
+   * Remove a {@link Persona} from the PersonaStore.
+   *
+   * See {@link Folks.PersonaStore.remove_persona}.
+   *
+   * @param persona the {@link Persona} to remove
+   * @throws Folks.PersonaStoreError.READ_ONLY every time since the
+   * Tracker backend is read-only.
+   *
+   * @since 0.9.6
+   */
+  public override async void remove_persona (Folks.Persona persona)
+      throws Folks.PersonaStoreError
+    {
+      throw new PersonaStoreError.READ_ONLY (
+          "Personas cannot be removed from this store.");
+    }
+
+  /**
+   * Add a new {@link Persona} to the PersonaStore.
+   *
+   * See {@link Folks.PersonaStore.add_persona_from_details}.
+   *
+   * @param details a map of keys to values giving the persona’s initial details
+   * @throws Folks.PersonaStoreError.READ_ONLY every time since the
+   * Tracker backend is read-only.
+   *
+   * @since 0.9.6
+   */
+  public override async Folks.Persona? add_persona_from_details (
+      HashTable<string, Value?> details) throws Folks.PersonaStoreError
+    {
+      throw new PersonaStoreError.READ_ONLY (
+          "Personas cannot be added to this store.");
+    }
+}
diff --git a/backends/tracker/tracker-persona.vala b/backends/tracker/tracker-persona.vala
new file mode 100644
index 00000000..90039c24
--- /dev/null
+++ b/backends/tracker/tracker-persona.vala
@@ -0,0 +1,234 @@
+/*
+ * Copyright 2023 Collabora Ltd.
+ *
+ * This library 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.
+ *
+ * This library 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 this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *       Corentin Noël <corentin.noel@collabora.com>
+ */
+
+using GLib;
+using Gee;
+using Folks;
+
+/**
+ * A persona subclass which represents a single persona from a simple key file.
+ *
+ * @since 0.9.6
+ */
+public class Folks.Backends.TrackerPersona : Folks.Persona,
+    AvatarDetails,
+    EmailDetails,
+    NameDetails,
+    PhoneDetails,
+    UrlDetails
+{
+  private const string[] _linkable_properties =
+    {
+      "phone-numbers",
+      "email-addresses"
+    };
+  private static string[] _writeable_properties = { };
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override string[] linkable_properties
+    {
+      get { return TrackerPersona._linkable_properties; }
+    }
+
+  private SmallSet<UrlFieldDetails>? _urls = null;
+  private Set<UrlFieldDetails> _urls_ro;
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  [CCode (notify = false)]
+  public Set<UrlFieldDetails> urls
+    {
+      get { return this._urls_ro; }
+      set { this.change_urls.begin (value); } /* not writeable */
+    }
+
+  private LoadableIcon? _avatar = null;
+
+  /**
+  * {@inheritDoc}
+  *
+  * @since 0.9.6
+  */
+  [CCode (notify = false)]
+  public LoadableIcon? avatar
+    {
+      get { return this._avatar; }
+      set { this.change_avatar.begin (value); }
+    }
+
+  /**
+  * {@inheritDoc}
+  *
+  * @since 0.9.6
+  */
+  public override string[] writeable_properties
+    {
+      get { return TrackerPersona._writeable_properties; }
+    }
+
+  private SmallSet<PhoneFieldDetails>? _phone_numbers = null;
+  private Set<PhoneFieldDetails> _phone_numbers_ro;
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  [CCode (notify = false)]
+  public Set<PhoneFieldDetails> phone_numbers
+    {
+      get { return this._phone_numbers_ro; }
+      set { this.change_phone_numbers.begin (value); } /* not writeable */
+    }
+
+  private StructuredName? _structured_name = null;
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  [CCode (notify = false)]
+  public StructuredName? structured_name
+    {
+      get { return this._structured_name; }
+      set { this.change_structured_name.begin (value); } /* not writeable */
+    }
+
+  private string _full_name = "";
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  [CCode (notify = false)]
+  public string full_name
+    {
+      get { return this._full_name; }
+      set { this.change_full_name.begin (value); } /* not writeable */
+    }
+
+  private string _nickname = "";
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  [CCode (notify = false)]
+  public string nickname
+    {
+      get { return this._nickname; }
+      set { this.change_nickname.begin (value); } /* not writeable */
+    }
+
+  private SmallSet<EmailFieldDetails>? _email_addresses = null;
+  private Set<EmailFieldDetails> _email_addresses_ro;
+  private Tracker.Sparql.Connection sparql_connection;
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  [CCode (notify = false)]
+  public Set<EmailFieldDetails> email_addresses
+    {
+      get { return this._email_addresses_ro; }
+      set { this.change_email_addresses.begin (value); } /* not writeable */
+    }
+
+  /**
+   * Create a new persona.
+   *
+   * Create a new persona for the {@link PersonaStore} ``store``, representing
+   * the Persona in the given ``vcard``.
+   *
+   * @param vcard the vCard stored as a string
+   * @param card a parsed version of the vCard
+   * @param store the store to which the Persona belongs.
+   * @param is_user whether the Persona is the user itself or not.
+   * @param iid pre-calculated IID for the persona
+   *
+   * @since 0.9.6
+   */
+  public TrackerPersona (Tracker.Sparql.Connection sparql_connection, Folks.PersonaStore store, string urn, string uid, string fullname)
+    {
+        Object(iid: urn, uid: uid, full_name: fullname, store: store);
+        this.sparql_connection = sparql_connection;
+    }
+
+  construct
+    {
+      debug ("Adding Tracker Persona '%s' (IID '%s')", this.uid, this.iid);
+
+      this._phone_numbers = new SmallSet<PhoneFieldDetails> (
+           AbstractFieldDetails<string>.hash_static,
+           AbstractFieldDetails<string>.equal_static);
+      this._phone_numbers_ro = this._phone_numbers.read_only_view;
+      this._email_addresses = new SmallSet<EmailFieldDetails> (
+           AbstractFieldDetails<string>.hash_static,
+           AbstractFieldDetails<string>.equal_static);
+      this._email_addresses_ro = this._email_addresses.read_only_view;
+      this._urls = new SmallSet<UrlFieldDetails> (
+           AbstractFieldDetails<string>.hash_static,
+           AbstractFieldDetails<string>.equal_static);
+      this._urls_ro = this._urls.read_only_view;
+    }
+
+  /**
+   * {@inheritDoc}
+   *
+   * @since 0.9.6
+   */
+  public override void linkable_property_to_links (string prop_name,
+      Folks.Persona.LinkablePropertyCallback callback)
+    {
+      if (prop_name == "phone-numbers")
+        {
+          foreach (var phone_number in this._phone_numbers)
+            {
+                if (phone_number.value != null)
+                    callback (phone_number.value);
+            }
+        }
+      else if (prop_name == "email-addresses")
+        {
+          foreach (var email_address in this._email_addresses)
+            {
+                if (email_address.value != null)
+                    callback (email_address.value);
+            }
+        }
+      else
+        {
+          /* Chain up */
+          base.linkable_property_to_links (prop_name, callback);
+        }
+    }
+}
diff --git a/meson.build b/meson.build
index 6bdaae27..d2d9bd7e 100644
--- a/meson.build
+++ b/meson.build
@@ -57,6 +57,7 @@ tests_enabled = get_option('tests')
 installed_tests_enabled = get_option('installed_tests')
 ofono_backend_enabled = get_option('ofono_backend')
 telepathy_backend_enabled = get_option('telepathy_backend')
+tracker_backend_enabled = get_option('tracker_backend')
 zeitgeist_enabled = get_option('zeitgeist')
 import_tool_enabled = get_option('import_tool')
 inspect_tool_enabled = get_option('inspect_tool')
@@ -122,6 +123,12 @@ if bluez_backend_enabled
   endif
 endif
 
+if tracker_backend_enabled
+  vapi_dir = meson.current_source_dir() / 'vapi'
+  add_project_arguments(['--vapidir', vapi_dir], language: 'vala')
+  tracker_dep = dependency('tracker-sparql-3.0')
+endif
+
 if import_tool_enabled
   libxml_dep = dependency('libxml-2.0')
 endif
diff --git a/meson_options.txt b/meson_options.txt
index 361f30cf..7aadf08d 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -3,6 +3,7 @@ option('bluez_backend', type: 'boolean', value: true, description: 'build the Bl
 option('eds_backend', type: 'boolean', value: true, description: 'build the E-D-S backend')
 option('ofono_backend', type: 'boolean', value: true, description: 'build the oFono backend')
 option('telepathy_backend', type: 'boolean', value: true, description: 'build the Telepathy backend')
+option('tracker_backend', type: 'boolean', value: true, description: 'build the Tracker backend')
 option('zeitgeist', type: 'boolean', value: false, description: 'build Zeitgeist support in the Telepathy backend')
 # Tools
 option('import_tool', type: 'boolean', value: true, description: 'Enable building the meta-contact import tool')
diff --git a/vapi/tracker-sparql-3.0.vapi b/vapi/tracker-sparql-3.0.vapi
new file mode 100644
index 00000000..ae0c2c11
--- /dev/null
+++ b/vapi/tracker-sparql-3.0.vapi
@@ -0,0 +1,344 @@
+/* tracker-sparql-3.0.vapi generated by vapigen, do not modify. */
+
+[CCode (cprefix = "Tracker", gir_namespace = "Tracker", gir_version = "3.0", lower_case_cprefix = "tracker_")]
+namespace Tracker {
+	namespace Prefix {
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_DC")]
+		public const string DC;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_MFO")]
+		public const string MFO;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_NAO")]
+		public const string NAO;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_NCO")]
+		public const string NCO;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_NFO")]
+		public const string NFO;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_NIE")]
+		public const string NIE;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_NMM")]
+		public const string NMM;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_NRL")]
+		public const string NRL;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_OSINFO")]
+		public const string OSINFO;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_RDF")]
+		public const string RDF;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_RDFS")]
+		public const string RDFS;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_SLO")]
+		public const string SLO;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_TRACKER")]
+		public const string TRACKER;
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cname = "TRACKER_PREFIX_XSD")]
+		public const string XSD;
+	}
+	namespace Sparql {
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_sparql_connection_get_type ()")]
+		[GIR (name = "SparqlConnection")]
+		public abstract class Connection : GLib.Object {
+			[CCode (has_construct_function = false)]
+			protected Connection ();
+			[Version (since = "3.0")]
+			public static Tracker.Sparql.Connection bus_new (string service_name, string? object_path, GLib.DBusConnection? dbus_connection) throws GLib.Error;
+			[Version (since = "3.1")]
+			public static async Tracker.Sparql.Connection bus_new_async (string service_name, string? object_path, GLib.DBusConnection? dbus_connection, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (since = "3.0")]
+			public void close ();
+			[Version (since = "3.0")]
+			public async bool close_async (GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public Tracker.Batch create_batch ();
+			public Tracker.Notifier create_notifier ();
+			[Version (since = "3.4")]
+			public async bool deserialize_async (Tracker.DeserializeFlags flags, Tracker.RdfFormat format, string default_graph, GLib.InputStream stream, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public unowned Tracker.NamespaceManager get_namespace_manager ();
+			[Version (since = "3.3")]
+			public Tracker.Sparql.Statement? load_statement_from_gresource (string resource_path, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (since = "3.3")]
+			public void map_connection (string handle_name, Tracker.Sparql.Connection service_connection);
+			[Version (since = "3.0")]
+			public static Tracker.Sparql.Connection @new (Tracker.Sparql.ConnectionFlags flags, GLib.File? store, GLib.File? ontology, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (since = "3.0")]
+			public static async Tracker.Sparql.Connection new_async (Tracker.Sparql.ConnectionFlags flags, GLib.File? store, GLib.File? ontology, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public Tracker.Sparql.Cursor query (string sparql, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public async Tracker.Sparql.Cursor query_async (string sparql, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public Tracker.Sparql.Statement? query_statement (string sparql, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public static Tracker.Sparql.Connection remote_new (string uri_base);
+			[Version (since = "3.3")]
+			public async GLib.InputStream serialize_async (Tracker.SerializeFlags flags, Tracker.RdfFormat format, string query, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public void update (string sparql, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public async bool update_array_async (string sparql, int sparql_length, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public async void update_async (string sparql, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (deprecated = true, deprecated_since = "3.5")]
+			public GLib.Variant update_blank (string sparql, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (deprecated = true, deprecated_since = "3.5")]
+			public async GLib.Variant update_blank_async (string sparql, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (since = "3.1")]
+			public bool update_resource (string? graph, Tracker.Resource resource, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (since = "3.1")]
+			public async bool update_resource_async (string? graph, Tracker.Resource resource, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (since = "3.5")]
+			public Tracker.Sparql.Statement? update_statement (string sparql, GLib.Cancellable? cancellable = null) throws GLib.Error;
+		}
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_sparql_cursor_get_type ()")]
+		[GIR (name = "SparqlCursor")]
+		public abstract class Cursor : GLib.Object {
+			[CCode (has_construct_function = false)]
+			protected Cursor ();
+			public void close ();
+			public bool get_boolean (int column);
+			public unowned Tracker.Sparql.Connection get_connection ();
+			[Version (since = "3.2")]
+			public GLib.DateTime? get_datetime (int column);
+			public double get_double (int column);
+			public int64 get_integer (int column);
+			public int get_n_columns ();
+			public unowned string? get_string (int column, out long length);
+			public Tracker.Sparql.ValueType get_value_type (int column);
+			public unowned string get_variable_name (int column);
+			public bool is_bound (int column);
+			public bool next (GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public async bool next_async (GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (deprecated = true, deprecated_since = "3.5")]
+			public void rewind ();
+			public Tracker.Sparql.Connection connection { get; construct; }
+			public int n_columns { get; }
+		}
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_sparql_statement_get_type ()")]
+		[GIR (name = "SparqlStatement")]
+		public abstract class Statement : GLib.Object {
+			[CCode (has_construct_function = false)]
+			protected Statement ();
+			public void bind_boolean (string name, bool value);
+			[Version (since = "3.2")]
+			public void bind_datetime (string name, GLib.DateTime value);
+			public void bind_double (string name, double value);
+			public void bind_int (string name, int64 value);
+			public void bind_string (string name, string value);
+			[Version (since = "3.0")]
+			public void clear_bindings ();
+			public Tracker.Sparql.Cursor execute (GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public async Tracker.Sparql.Cursor execute_async (GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public unowned Tracker.Sparql.Connection get_connection ();
+			public unowned string get_sparql ();
+			[Version (since = "3.3")]
+			public async GLib.InputStream serialize_async (Tracker.SerializeFlags flags, Tracker.RdfFormat format, GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (since = "3.5")]
+			public bool update (GLib.Cancellable? cancellable = null) throws GLib.Error;
+			[Version (since = "3.5")]
+			public async bool update_async (GLib.Cancellable? cancellable = null) throws GLib.Error;
+			public Tracker.Sparql.Connection connection { get; construct; }
+			public string sparql { get; construct; }
+		}
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cprefix = "TRACKER_SPARQL_CONNECTION_FLAGS_", has_type_id = false)]
+		[Flags]
+		[GIR (name = "SparqlConnectionFlags")]
+		public enum ConnectionFlags {
+			NONE,
+			READONLY,
+			FTS_ENABLE_STEMMER,
+			FTS_ENABLE_UNACCENT,
+			FTS_ENABLE_STOP_WORDS,
+			FTS_IGNORE_NUMBERS,
+			ANONYMOUS_BNODES
+		}
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cprefix = "TRACKER_SPARQL_VALUE_TYPE_", has_type_id = false)]
+		[GIR (name = "SparqlValueType")]
+		public enum ValueType {
+			UNBOUND,
+			URI,
+			STRING,
+			INTEGER,
+			DOUBLE,
+			DATETIME,
+			BLANK_NODE,
+			BOOLEAN
+		}
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cprefix = "TRACKER_SPARQL_ERROR_", has_type_id = false)]
+		[GIR (name = "SparqlError")]
+		public errordomain Error {
+			CONSTRAINT,
+			INTERNAL,
+			NO_SPACE,
+			ONTOLOGY_NOT_FOUND,
+			OPEN_ERROR,
+			PARSE,
+			QUERY_FAILED,
+			TYPE,
+			UNKNOWN_CLASS,
+			UNKNOWN_GRAPH,
+			UNKNOWN_PROPERTY,
+			UNSUPPORTED,
+			MISSING_LAST_MODIFIED_HEADER,
+			INCOMPLETE_PROPERTY_DEFINITION,
+			LAST;
+			public static GLib.Quark quark ();
+		}
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h")]
+		public static string escape_string (string literal);
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h")]
+		public static string escape_uri (string uri);
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h")]
+		public static string escape_uri_printf (string format, ...);
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h")]
+		public static string escape_uri_vprintf (string format, va_list args);
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h")]
+		public static GLib.File get_ontology_nepomuk ();
+		[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h")]
+		public static string get_uuid_urn ();
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_batch_get_type ()")]
+	public abstract class Batch : GLib.Object {
+		[CCode (has_construct_function = false)]
+		protected Batch ();
+		[Version (since = "3.1")]
+		public void add_resource (string? graph, Tracker.Resource resource);
+		[Version (since = "3.1")]
+		public void add_sparql (string sparql);
+		[Version (since = "3.5")]
+		public void add_statementv (Tracker.Sparql.Statement stmt, [CCode (array_length_cname = "n_values", array_length_pos = 1.5, array_length_type = "guint")] string[] variable_names, [CCode (array_length_cname = "n_values", array_length_pos = 1.5, array_length_type = "guint")] GLib.Value[] values);
+		[Version (since = "3.1")]
+		public bool execute (GLib.Cancellable? cancellable = null) throws GLib.Error;
+		[Version (since = "3.1")]
+		public async bool execute_async (GLib.Cancellable? cancellable = null) throws GLib.Error;
+		public unowned Tracker.Sparql.Connection get_connection ();
+		public Tracker.Sparql.Connection connection { get; construct; }
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_endpoint_get_type ()")]
+	public abstract class Endpoint : GLib.Object {
+		[CCode (has_construct_function = false)]
+		protected Endpoint ();
+		public unowned Tracker.Sparql.Connection get_sparql_connection ();
+		public Tracker.Sparql.Connection sparql_connection { get; construct; }
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_endpoint_dbus_get_type ()")]
+	public class EndpointDBus : Tracker.Endpoint, GLib.Initable {
+		[CCode (has_construct_function = false)]
+		public EndpointDBus (Tracker.Sparql.Connection sparql_connection, GLib.DBusConnection dbus_connection, string? object_path, GLib.Cancellable? cancellable = null) throws GLib.Error;
+		[NoAccessorMethod]
+		public GLib.DBusConnection dbus_connection { owned get; construct; }
+		[NoAccessorMethod]
+		public string object_path { owned get; construct; }
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_endpoint_http_get_type ()")]
+	public class EndpointHttp : Tracker.Endpoint, GLib.Initable {
+		[CCode (has_construct_function = false)]
+		[Version (since = "3.1")]
+		public EndpointHttp (Tracker.Sparql.Connection sparql_connection, uint port, GLib.TlsCertificate? certificate, GLib.Cancellable? cancellable = null) throws GLib.Error;
+		[NoAccessorMethod]
+		public GLib.TlsCertificate http_certificate { owned get; construct; }
+		[NoAccessorMethod]
+		public uint http_port { get; construct; }
+		public signal bool block_remote_address (GLib.SocketAddress address);
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_namespace_manager_get_type ()")]
+	public class NamespaceManager : GLib.Object {
+		[CCode (has_construct_function = false)]
+		public NamespaceManager ();
+		public void add_prefix (string prefix, string ns);
+		[Version (since = "3.3")]
+		public string compress_uri (string uri);
+		public string expand_uri (string compact_uri);
+		public void @foreach (GLib.HFunc func);
+		[Version (deprecated = true, deprecated_since = "3.3")]
+		public static unowned Tracker.NamespaceManager get_default ();
+		public bool has_prefix (string prefix);
+		public unowned string? lookup_prefix (string prefix);
+		public string print_turtle ();
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_notifier_get_type ()")]
+	public class Notifier : GLib.Object {
+		[CCode (has_construct_function = false)]
+		protected Notifier ();
+		[Version (since = "3.0")]
+		public uint signal_subscribe (GLib.DBusConnection connection, string service, string? object_path, string? graph);
+		[Version (since = "3.0")]
+		public void signal_unsubscribe (uint handler_id);
+		[NoAccessorMethod]
+		public Tracker.Sparql.Connection connection { owned get; construct; }
+		public signal void events (string service, string graph, GLib.GenericArray<Tracker.NotifierEvent> events);
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", copy_function = "g_boxed_copy", free_function = "g_boxed_free", type_id = "tracker_notifier_event_get_type ()")]
+	[Compact]
+	public class NotifierEvent {
+		public Tracker.NotifierEventType get_event_type ();
+		public int64 get_id ();
+		public unowned string get_urn ();
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", type_id = "tracker_resource_get_type ()")]
+	public class Resource : GLib.Object {
+		[CCode (has_construct_function = false)]
+		public Resource (string? identifier);
+		public void add_boolean (string property_uri, bool value);
+		[Version (since = "3.2")]
+		public void add_datetime (string property_uri, GLib.DateTime value);
+		public void add_double (string property_uri, double value);
+		public void add_gvalue (string property_uri, GLib.Value value);
+		public void add_int (string property_uri, int value);
+		public void add_int64 (string property_uri, int64 value);
+		public void add_relation (string property_uri, Tracker.Resource resource);
+		public void add_string (string property_uri, string value);
+		public void add_take_relation (string property_uri, owned Tracker.Resource resource);
+		public void add_uri (string property_uri, string value);
+		public static Tracker.Resource? deserialize (GLib.Variant variant);
+		public bool get_first_boolean (string property_uri);
+		[Version (since = "3.2")]
+		public unowned GLib.DateTime? get_first_datetime (string property_uri);
+		public double get_first_double (string property_uri);
+		public int get_first_int (string property_uri);
+		public int64 get_first_int64 (string property_uri);
+		public unowned Tracker.Resource? get_first_relation (string property_uri);
+		public unowned string? get_first_string (string property_uri);
+		public unowned string? get_first_uri (string property_uri);
+		public unowned string? get_identifier ();
+		[Version (since = "3.0")]
+		public GLib.List<weak string> get_properties ();
+		[Version (since = "3.1")]
+		public bool get_property_overwrite (string property_uri);
+		public GLib.List<weak GLib.Value?>? get_values (string property_uri);
+		public int identifier_compare_func (string identifier);
+		[Version (deprecated = true, deprecated_since = "3.5")]
+		public string print_jsonld (Tracker.NamespaceManager? namespaces);
+		[Version (since = "3.4")]
+		public string print_rdf (Tracker.NamespaceManager namespaces, Tracker.RdfFormat format, string? graph);
+		public string print_sparql_update (Tracker.NamespaceManager? namespaces, string? graph_id);
+		[Version (deprecated = true, deprecated_since = "3.4")]
+		public string print_turtle (Tracker.NamespaceManager? namespaces);
+		public unowned GLib.Variant? serialize ();
+		public void set_boolean (string property_uri, bool value);
+		[Version (since = "3.2")]
+		public void set_datetime (string property_uri, GLib.DateTime value);
+		public void set_double (string property_uri, double value);
+		public void set_gvalue (string property_uri, GLib.Value value);
+		public void set_identifier (string? identifier);
+		public void set_int (string property_uri, int value);
+		public void set_int64 (string property_uri, int64 value);
+		public void set_relation (string property_uri, Tracker.Resource resource);
+		public void set_string (string property_uri, string value);
+		public void set_take_relation (string property_uri, owned Tracker.Resource resource);
+		public void set_uri (string property_uri, string value);
+		public string identifier { get; set; }
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cprefix = "TRACKER_DESERIALIZE_FLAGS_", has_type_id = false)]
+	public enum DeserializeFlags {
+		NONE
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cprefix = "TRACKER_NOTIFIER_EVENT_", has_type_id = false)]
+	public enum NotifierEventType {
+		CREATE,
+		DELETE,
+		UPDATE
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cprefix = "TRACKER_RDF_FORMAT_", has_type_id = false)]
+	public enum RdfFormat {
+		TURTLE,
+		TRIG,
+		JSON_LD,
+		LAST
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h", cprefix = "TRACKER_SERIALIZE_FLAGS_", has_type_id = false)]
+	public enum SerializeFlags {
+		NONE
+	}
+	[CCode (cheader_filename = "libtracker-sparql/tracker-sparql.h")]
+	public static unowned string check_version (uint required_major, uint required_minor, uint required_micro);
+}