tracker3: Port to new API

12 files changed, 131 insertions, 77 deletions

diff --git a/src/plugins/tracker3/rygel-tracker-category-all-container.vala b/src/plugins/tracker3/rygel-tracker-category-all-container.vala
index 64ab3aa7..5a2695b8 100644
--- a/src/plugins/tracker3/rygel-tracker-category-all-container.vala
+++ b/src/plugins/tracker3/rygel-tracker-category-all-container.vala
@@ -33,14 +33,13 @@ public class Rygel.Tracker.CategoryAllContainer : SearchContainer,
                                                   WritableContainer,
                                                   SearchableContainer {
     /* class-wide constants */
-    private const string TRACKER_SERVICE = "org.freedesktop.Tracker1";
-    private const string RESOURCES_PATH = "/org/freedesktop/Tracker1/Resources";
+    private const string TRACKER_SERVICE = "org.freedesktop.Tracker3.Miner.Files";
+    private const string RESOURCES_PATH = "/org/freedesktop/Tracker3/Endpoint";
+    private const string TRACKER_INTERFACE = "org.freedesktop.Tracker3.Endpoint";
 
     public ArrayList<string> create_classes { get; set; }
     public ArrayList<string> search_classes { get; set; }
 
-    private Sparql.Connection resources;
-
     public CategoryAllContainer (CategoryContainer parent) {
         base ("All" + parent.id, parent, "All", parent.item_factory);
 
@@ -48,13 +47,6 @@ public class Rygel.Tracker.CategoryAllContainer : SearchContainer,
         this.create_classes.add (item_factory.upnp_class);
         this.search_classes = new ArrayList<string> ();
 
-        try {
-            this.resources = Sparql.Connection.bus_new ("org.freedesktop.Tracker3.Miner.Files", null);
-        } catch (Error io_error) {
-            critical (_("Failed to create a Tracker connection: %s"),
-                      io_error.message);
-        }
-
         if (item_factory.upload_dir != null) {
             try {
                 var uri = Filename.to_uri (item_factory.upload_dir, null);
@@ -69,7 +61,7 @@ public class Rygel.Tracker.CategoryAllContainer : SearchContainer,
         try {
             var connection = Bus.get_sync (BusType.SESSION);
             connection.signal_subscribe (TRACKER_SERVICE,
-                                         TRACKER_SERVICE + ".Resources",
+                                         TRACKER_INTERFACE,
                                          "GraphUpdated",
                                          RESOURCES_PATH,
                                          this.item_factory.category_iri,
@@ -80,8 +72,9 @@ public class Rygel.Tracker.CategoryAllContainer : SearchContainer,
                       error.message);
         }
 
+        message("RUnnin cleanup query for %s", this.item_factory.category);
         var cleanup_query = new CleanupQuery (this.item_factory.category);
-        cleanup_query.execute.begin (this.resources);
+        cleanup_query.execute.begin (RootContainer.connection, () => { query.result.close (); } );
     }
 
     public async void add_item (MediaFileItem item, Cancellable? cancellable)
@@ -140,7 +133,7 @@ public class Rygel.Tracker.CategoryAllContainer : SearchContainer,
         var category = this.item_factory.category;
         var query = new InsertionQuery (item, category);
 
-        yield query.execute (this.resources);
+        yield query.execute (RootContainer.connection);
 
         return query.id;
     }
@@ -148,6 +141,6 @@ public class Rygel.Tracker.CategoryAllContainer : SearchContainer,
     private async void remove_entry_from_store (string id) throws Error {
         var query = new DeletionQuery (id);
 
-        yield query.execute (this.resources);
+        yield query.execute (RootContainer.connection);
     }
 }
diff --git a/src/plugins/tracker3/rygel-tracker-insertion-query.vala b/src/plugins/tracker3/rygel-tracker-insertion-query.vala
index e062d058..4d5323a6 100644
--- a/src/plugins/tracker3/rygel-tracker-insertion-query.vala
+++ b/src/plugins/tracker3/rygel-tracker-insertion-query.vala
@@ -152,6 +152,7 @@ public class Rygel.Tracker.InsertionQuery : Query {
                 }
             } catch (Error error) {
             }
+            cursor.close ();
         } else {
             var file = File.new_for_uri (this.uri);
             if (file.is_native () &&
diff --git a/src/plugins/tracker3/rygel-tracker-metadata-container.vala b/src/plugins/tracker3/rygel-tracker-metadata-container.vala
index 1637fef3..72180386 100644
--- a/src/plugins/tracker3/rygel-tracker-metadata-container.vala
+++ b/src/plugins/tracker3/rygel-tracker-metadata-container.vala
@@ -39,7 +39,6 @@ public abstract class Rygel.Tracker.MetadataContainer : Rygel.SimpleContainer {
 
     private string child_class;
 
-    private Sparql.Connection resources;
     protected QueryTriplets triplets;
 
     protected MetadataContainer (string         id,
@@ -51,15 +50,6 @@ public abstract class Rygel.Tracker.MetadataContainer : Rygel.SimpleContainer {
 
         this.item_factory = item_factory;
         this.child_class = child_class;
-
-        try {
-            this.resources = Sparql.Connection.bus_new ("org.freedesktop.Tracker3.Miner.Files", null);
-        } catch (Error error) {
-            critical (_("Failed to create Tracker connection: %s"),
-                      error.message);
-
-            return;
-        }
     }
 
     internal async void fetch_metadata_values () {
@@ -74,7 +64,7 @@ public abstract class Rygel.Tracker.MetadataContainer : Rygel.SimpleContainer {
         var query = this.create_query ();
 
         try {
-            yield query.execute (this.resources);
+            yield query.execute (RootContainer.connection);
 
             /* Iterate through all the values */
             while (query.result.next ()) {
@@ -106,6 +96,8 @@ public abstract class Rygel.Tracker.MetadataContainer : Rygel.SimpleContainer {
 
                 this.add_child_container (container);
             }
+
+            query.result.close ();
         } catch (Error error) {
             critical (_("Error getting all values for “%s”: %s"),
                       this.id,
diff --git a/src/plugins/tracker3/rygel-tracker-metadata-values.vala b/src/plugins/tracker3/rygel-tracker-metadata-values.vala
index e9fd1606..1c443df7 100644
--- a/src/plugins/tracker3/rygel-tracker-metadata-values.vala
+++ b/src/plugins/tracker3/rygel-tracker-metadata-values.vala
@@ -48,6 +48,9 @@ public abstract class Rygel.Tracker.MetadataValues : MetadataContainer {
         this.triplets.add (new QueryTriplet (SelectionQuery.ITEM_VARIABLE,
                                              "a",
                                              this.item_factory.category));
+        this.triplets.add (new QueryTriplet (SelectionQuery.ITEM_VARIABLE,
+                                             "nie:isStoredAs",
+                                             SelectionQuery.STORAGE_VARIABLE));
         this.fetch_metadata_values.begin ();
     }
 
@@ -58,7 +61,9 @@ public abstract class Rygel.Tracker.MetadataValues : MetadataContainer {
                       property_map[this.property] +
                       " AS ?x");
 
-        return new SelectionQuery (selected, triplets, null, "?x");
+        var q = new SelectionQuery (selected, triplets, null, "?x");
+        critical(q.to_string());
+        return q;
     }
 
     protected override SearchContainer create_container (string id,
diff --git a/src/plugins/tracker3/rygel-tracker-music.vala b/src/plugins/tracker3/rygel-tracker-music.vala
index dc81cf00..f0f9abb9 100644
--- a/src/plugins/tracker3/rygel-tracker-music.vala
+++ b/src/plugins/tracker3/rygel-tracker-music.vala
@@ -31,8 +31,8 @@ public class Rygel.Tracker.Music : CategoryContainer {
         base (id, parent, title, new MusicItemFactory ());
 
         this.add_child_container (new Artists (this));
-        this.add_child_container (new Albums (this));
-        this.add_child_container (new Genre (this));
+        //this.add_child_container (new Albums (this));
+        //this.add_child_container (new Genre (this));
         this.search_classes.add (AudioItem.UPNP_CLASS);
         this.search_classes.add (MusicItem.UPNP_CLASS);
         this.add_create_class (AudioItem.UPNP_CLASS);
diff --git a/src/plugins/tracker3/rygel-tracker-new.vala b/src/plugins/tracker3/rygel-tracker-new.vala
index efabcc86..f2055b97 100644
--- a/src/plugins/tracker3/rygel-tracker-new.vala
+++ b/src/plugins/tracker3/rygel-tracker-new.vala
@@ -29,7 +29,6 @@ using Gee;
 public class Rygel.Tracker.New : Rygel.Tracker.SearchContainer {
     private const string ADDED_PREDICATE = "tracker:added";
     private const string ADDED_VARIABLE = "?added";
-    private const long THREE_DAYS_AS_SEC = 259200;
 
     public New (MediaContainer parent, ItemFactory item_factory) {
         var triplets = new QueryTriplets ();
@@ -42,11 +41,11 @@ public class Rygel.Tracker.New : Rygel.Tracker.SearchContainer {
                                         ADDED_VARIABLE));
 
         var now = new DateTime.now_utc ();
-        now.add_days (-3);
+        now = now.add_days (-3);
         var three_days_ago = "%sZ".printf (now.format ("%Y-%m-%dT%H:%M:%S"));
 
         var filters = new ArrayList<string> ();
-        filters.add (ADDED_VARIABLE + " > \"" + three_days_ago + "\"");
+        filters.add (ADDED_VARIABLE + " > \"" + three_days_ago + "\"^^xsd:dateTime");
 
         base (parent.id + "New",
               parent,
diff --git a/src/plugins/tracker3/rygel-tracker-plugin-factory.vala b/src/plugins/tracker3/rygel-tracker-plugin-factory.vala
index e7c74c92..06f8149b 100644
--- a/src/plugins/tracker3/rygel-tracker-plugin-factory.vala
+++ b/src/plugins/tracker3/rygel-tracker-plugin-factory.vala
@@ -38,22 +38,11 @@ public void module_init (PluginLoader loader) {
 }
 
 public class Rygel.Tracker.PluginFactory {
-    private const string TRACKER_SERVICE = "org.freedesktop.Tracker1";
-    private const string STATISTICS_OBJECT =
-                                        "/org/freedesktop/Tracker1/Statistics";
-
-    StatsIface stats;
     PluginLoader loader;
 
     public PluginFactory (PluginLoader loader) throws IOError, DBusError {
-        this.stats = Bus.get_proxy_sync (BusType.SESSION,
-                                         TRACKER_SERVICE,
-                                         STATISTICS_OBJECT,
-                                         DBusProxyFlags.DO_NOT_LOAD_PROPERTIES);
         this.loader = loader;
 
-        this.stats.get ();
-
         this.loader.add_plugin (new Tracker.Plugin ());
     }
 }
diff --git a/src/plugins/tracker3/rygel-tracker-plugin.vala b/src/plugins/tracker3/rygel-tracker-plugin.vala
index d01cb528..84a29369 100644
--- a/src/plugins/tracker3/rygel-tracker-plugin.vala
+++ b/src/plugins/tracker3/rygel-tracker-plugin.vala
@@ -21,9 +21,10 @@
  */
 
 using Gee;
+using Tracker;
 
 public class Rygel.Tracker.Plugin : Rygel.MediaServerPlugin {
-    public const string NAME = "Tracker";
+    public const string NAME = "Tracker3";
 
     private static RootContainer root;
 
diff --git a/src/plugins/tracker3/rygel-tracker-root-container.vala b/src/plugins/tracker3/rygel-tracker-root-container.vala
index 88a7d3af..c5d3b25a 100644
--- a/src/plugins/tracker3/rygel-tracker-root-container.vala
+++ b/src/plugins/tracker3/rygel-tracker-root-container.vala
@@ -24,11 +24,24 @@
 
 using GUPnP;
 using Gee;
+using Tracker;
 
 /**
  * Represents the root container for Tracker media content hierarchy.
  */
 public class Rygel.Tracker.RootContainer : Rygel.SimpleContainer {
+    private const string TRACKER_SERVICE = "org.freedesktop.Tracker3.Miner.Files";
+
+    public static Sparql.Connection connection;
+
+    static construct {
+        try {
+            RootContainer.connection = Sparql.Connection.bus_new (TRACKER_SERVICE, null);
+        } catch (Error err) {
+            error ("Failed to connect to tracker: %s", err.message);
+        }
+    }
+
     public RootContainer (string title) {
         base.root (title);
 
@@ -52,7 +65,7 @@ public class Rygel.Tracker.RootContainer : Rygel.SimpleContainer {
         var config = MetaConfig.get_default ();
 
         try {
-            value = config.get_bool ("Tracker", key);
+            value = config.get_bool ("Tracker3", key);
         } catch (GLib.Error error) {}
 
         return value;
diff --git a/src/plugins/tracker3/rygel-tracker-search-container.vala b/src/plugins/tracker3/rygel-tracker-search-container.vala
index 4310e090..965d8294 100644
--- a/src/plugins/tracker3/rygel-tracker-search-container.vala
+++ b/src/plugins/tracker3/rygel-tracker-search-container.vala
@@ -38,7 +38,9 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
     public SelectionQuery query;
     public ItemFactory item_factory;
 
-    private Sparql.Connection resources;
+    static construct {
+        update_id_hash = new HashMap<string, uint> ();
+    }
 
     private static HashMap<string, uint> update_id_hash;
 
@@ -50,10 +52,6 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
                             ArrayList<string>? filters = null) {
         base (id, parent, title);
 
-        if (unlikely (update_id_hash == null)) {
-            update_id_hash = new HashMap<string, uint> ();
-        }
-
         if (update_id_hash.has_key (this.id)) {
             this.update_id = update_id_hash[this.id];
         }
@@ -80,6 +78,10 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
                                 (SelectionQuery.ITEM_VARIABLE,
                                  "a",
                                  item_factory.category));
+        our_triplets.add (new QueryTriplet
+                                (SelectionQuery.ITEM_VARIABLE,
+                                 "nie:isStoredAs",
+                                SelectionQuery.STORAGE_VARIABLE));
 
         var property_map = UPnPPropertyMap.get_property_map ();
         foreach (var property in this.item_factory.properties) {
@@ -88,7 +90,7 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
 
         var order_by = MODIFIED_PROPERTY +
                        "(" +
-                       SelectionQuery.ITEM_VARIABLE +
+                       SelectionQuery.STORAGE_VARIABLE +
                        ")";
 
         this.query = new SelectionQuery (variables,
@@ -96,13 +98,7 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
                                          filters,
                                          order_by);
 
-        try {
-            this.resources = Sparql.Connection.bus_new ("org.freedesktop.Tracker3.Miner.Files", null);
-
-            this.get_children_count.begin ();
-        } catch (Error error) {
-            critical (_("Failed to get Tracker connection: %s"), error.message);
-        }
+        this.get_children_count.begin ();
     }
 
     public override async MediaObjects? get_children (uint       offset,
@@ -140,7 +136,7 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
                                        sort_criteria);
 
         if (query != null) {
-            yield query.execute (this.resources);
+            yield query.execute (RootContainer.connection);
 
             /* Iterate through all items */
             while (yield query.result.next_async ()) {
@@ -154,6 +150,8 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
                                                      query.result);
                 results.add (item);
             }
+
+            query.result.close ();
         }
 
         total_matches = results.size;
@@ -217,13 +215,14 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
                                  SelectionQuery.ITEM_VARIABLE +
                                  ") AS ?x");
 
-            yield query.execute (this.resources);
+            yield query.execute (RootContainer.connection);
 
             if (query.result.next ()) {
                 this.child_count = int.parse (query.result.get_string (0));
                 this.updated ();
             }
 
+            query.result.close ();
         } catch (GLib.Error error) {
             critical (_("Error getting item count under category “%s”: %s"),
                       this.item_factory.category,
@@ -284,10 +283,12 @@ public class Rygel.Tracker.SearchContainer : SimpleContainer {
 
          foreach (string s in sort_props) {
              var key = key_chain_map[s.substring(1)];
-             if (key.index_of (SelectionQuery.ITEM_VARIABLE) == 0) {
+             if (key.index_of (SelectionQuery.ITEM_VARIABLE) == 0 ||
+                 key.index_of (SelectionQuery.STORAGE_VARIABLE) == 0) {
                  continue;
              }
 
+
              if (s.has_prefix("-")) {
                  order += "DESC (" +
                            key + ") ";
diff --git a/src/plugins/tracker3/rygel-tracker-selection-query.vala b/src/plugins/tracker3/rygel-tracker-selection-query.vala
index 9a0f8282..7fd9c580 100644
--- a/src/plugins/tracker3/rygel-tracker-selection-query.vala
+++ b/src/plugins/tracker3/rygel-tracker-selection-query.vala
@@ -29,17 +29,19 @@ using Tracker;
  */
 public class Rygel.Tracker.SelectionQuery : Query {
     public const string ITEM_VARIABLE = "?item";
-    private const string SHARED_FILTER = "(!BOUND(nmm:uPnPShared(" +
+    public const string STORAGE_VARIABLE = "?storage";
+
+    private const string SHARED_FILTER = ""; /*"(!BOUND(nmm:uPnPShared(" +
                                          ITEM_VARIABLE + ")) ||" +
                                          " nmm:uPnPShared(" +
                                          ITEM_VARIABLE +
                                          ") = true) && " +
-                                         "(BOUND(nie:url(" +
-                                         ITEM_VARIABLE + ")))";
+                                         "(BOUND(nie:isStoredAs(" +
+                                         ITEM_VARIABLE + ")))";*/
     private const string STRICT_SHARED_FILTER = "(BOUND(nmm:dlnaProfile(" +
                                                 ITEM_VARIABLE + ")))";
-    private const string AVAILABLE_FILTER = "(tracker:available(" +
-                                            ITEM_VARIABLE + ") = true)";
+    private const string AVAILABLE_FILTER = "(tracker:available(nie:isStoredAs(" +
+                                            ITEM_VARIABLE + ")) = true)";
 
     private string uri_filter;
 
@@ -77,7 +79,7 @@ public class Rygel.Tracker.SelectionQuery : Query {
         var config = MetaConfig.get_default ();
 
         try {
-            uris = config.get_string_list ("Tracker", "only-export-from");
+            uris = config.get_string_list ("Tracker3", "only-export-from");
         } catch (Error error) {
             uris = new ArrayList<string> ();
         }
@@ -162,17 +164,17 @@ public class Rygel.Tracker.SelectionQuery : Query {
         var filters = new ArrayList<string> ();
         filters.add_all (this.filters);
         // Make sure we don't expose items that are marked not to be shared
-        filters.add (SHARED_FILTER);
+        // filters.add (SHARED_FILTER);
 
         // Make sure we don't expose items on removable media that isn't
         // mounted
-        filters.add (AVAILABLE_FILTER);
+        //filters.add (AVAILABLE_FILTER);
 
         // If strict sharing is enabled, only expose files that have a DLNA
         // profile set
         try {
             var config = MetaConfig.get_default ();
-            if (config.get_bool ("Tracker", "strict-sharing")) {
+            if (config.get_bool ("Tracker3", "strict-sharing")) {
                 filters.add (STRICT_SHARED_FILTER);
             }
         } catch (Error error) {};
diff --git a/src/plugins/tracker3/rygel-tracker-upnp-property-map.vala b/src/plugins/tracker3/rygel-tracker-upnp-property-map.vala
index 7670b57c..298d0eea 100644
--- a/src/plugins/tracker3/rygel-tracker-upnp-property-map.vala
+++ b/src/plugins/tracker3/rygel-tracker-upnp-property-map.vala
@@ -23,6 +23,16 @@
 
 using Gee;
 
+internal class Rygel.Tracker.QueryVariable {
+    public string base_variable;
+    public string alias;
+
+    public QueryVariable(string base_variable, string alias) {
+        this.base_variable = base_variable;
+        this.alias = alias;
+    }
+}
+
 /**
  * A map of UPnP properties to tracker property functions, coalesces,
  * subqueries or other custom functions
@@ -30,6 +40,7 @@ using Gee;
 public class Rygel.Tracker.UPnPPropertyMap : Object {
     HashMap<string, ArrayList<string>> property_map;
     HashMap<string, string> functions;
+    HashMap<string, QueryVariable> variables;
     private static UPnPPropertyMap instance;
 
     public static UPnPPropertyMap get_property_map () {
@@ -43,45 +54,84 @@ public class Rygel.Tracker.UPnPPropertyMap : Object {
     private UPnPPropertyMap () {
         this.property_map = new HashMap<string, ArrayList<string>> ();
         this.functions = new HashMap<string, string> ();
+        this.variables = new HashMap<string, QueryVariable> ();
+
+        this.add_variable ("upnp:class", SelectionQuery.ITEM_VARIABLE, "?_cls");
 
         // Item
         this.add_key_chain ("res", "nie:url");
+        this.add_variable ("res", SelectionQuery.STORAGE_VARIABLE, "?_url");
         this.add_function ("place_holder",
                       "tracker:coalesce((SELECT false WHERE { { %s a ?o } " +
                       "FILTER (?o IN (nfo:FileDataObject, " +
                       "nfo:RemoteDataObject)) }), true)");
+        this.add_variable ("place_holder", SelectionQuery.STORAGE_VARIABLE, "?_ph");
         this.add_key_chain ("fileName", "nfo:fileName");
-        this.add_alternative ("dc:title", "nie:title", "nfo:fileName");
+        this.add_variable ("fileName", SelectionQuery.STORAGE_VARIABLE, "?_fn");
+
+        this.add_alternative ("dc:title", "nie:title", "?_fn");
+        this.add_function ("dc:title", "tracker:coalesce(nie:title(%s), nfo:fileName(?storage))");
+        this.add_variable ("dc:title", SelectionQuery.ITEM_VARIABLE, "?_title");
+
         this.add_key_chain ("dlnaProfile", "nmm:dlnaProfile");
+        this.add_variable ("dlnaProfile", SelectionQuery.ITEM_VARIABLE, "?_profile");
+
         this.add_alternative ("mimeType", "nmm:dlnaMime", "nie:mimeType");
+        this.add_variable ("mimeType", SelectionQuery.ITEM_VARIABLE, "?_mime");
+
         this.add_alternative ("res@size", "nfo:fileSize", "nie:byteSize");
-        this.add_alternative ("date",
-                              "nie:contentCreated",
-                              "nfo:fileLastModified");
+        this.add_variable ("res@size", SelectionQuery.STORAGE_VARIABLE, "?_mime");
+
+        this.add_function ("date", "tracker:coalesce(nie:contentCreated(%s), nfo:fileLastModified(?storage))");
+        this.add_variable ("date", SelectionQuery.ITEM_VARIABLE, "?_date");
 
         // Music Item
         this.add_key_chain ("res@duration", "nfo:duration");
+        this.add_variable ("res@duration", SelectionQuery.ITEM_VARIABLE, "?_duration");
+
         this.add_key_chain ("upnp:artist", "nmm:performer", "nmm:artistName");
+        this.add_variable ("upnp:artist", SelectionQuery.ITEM_VARIABLE, "?_artist");
+
         this.add_key_chain ("dc:creator", "nmm:performer", "nmm:artistName");
+        this.add_variable ("dc:creator", SelectionQuery.ITEM_VARIABLE, "?_artist");
+
         this.add_key_chain ("upnp:album", "nmm:musicAlbum", "nie:title");
+        this.add_variable ("upnp:album", SelectionQuery.ITEM_VARIABLE, "?_album");
+
         this.add_key_chain ("upnp:originalTrackNumber", "nmm:trackNumber");
+        this.add_variable ("upnp:originalTrackNumber", SelectionQuery.ITEM_VARIABLE, "?_track");
+
         this.add_key_chain ("upnp:genre", "nfo:genre");
+        this.add_variable ("upnp:genre", SelectionQuery.ITEM_VARIABLE, "?_genre");
+
         this.add_key_chain ("sampleRate", "nfo:sampleRate");
+        this.add_variable ("sampleRate", SelectionQuery.ITEM_VARIABLE, "?_rate");
+
         this.add_key_chain ("upnp:nrAudioChannels", "nfo:channels");
+        this.add_variable ("upnp:nrAudioChannels", SelectionQuery.ITEM_VARIABLE, "?_channels");
+
         this.add_key_chain ("upnp:bitsPerSample", "nfo:bitsPerSample");
+        this.add_variable ("upnp:bitsPerSample", SelectionQuery.ITEM_VARIABLE, "?_bps");
+
         this.add_key_chain ("upnp:bitrate", "nfo:averageBitrate");
+        this.add_variable ("upnp:bitrate", SelectionQuery.ITEM_VARIABLE, "?_rate");
 
         // Picture & Video Items
         this.add_key_chain ("width", "nfo:width");
+        this.add_variable ("width", SelectionQuery.ITEM_VARIABLE, "?_w");
+
         this.add_key_chain ("height", "nfo:height");
+        this.add_variable ("height", SelectionQuery.ITEM_VARIABLE, "?_h");
 
         this.add_key_chain ("rygel:originalVolumeNumber",
                             "nmm:musicAlbumDisc",
                             "nmm:setNumber");
+        this.add_variable ("rygel:originalVolumeNumber", SelectionQuery.ITEM_VARIABLE, "?_vol");
     }
 
     public new string @get (string property) {
-        var str = SelectionQuery.ITEM_VARIABLE;
+        var variable = this.variables[property];
+        var str = variable.base_variable;
 
         if (this.property_map.has_key (property)) {
             foreach (var key in this.property_map[property]) {
@@ -91,7 +141,11 @@ public class Rygel.Tracker.UPnPPropertyMap : Object {
             str = this.functions[property].printf (str);
         }
 
-        return str;
+        return str; // + " AS " + variable.alias;
+    }
+
+    private void add_variable (string property, string base_item, string alias) {
+        this.variables[property] = new QueryVariable(base_item, alias);
     }
 
     private void add_key_chain (string property, ...) {
@@ -120,7 +174,11 @@ public class Rygel.Tracker.UPnPPropertyMap : Object {
 
         string alternative = list.arg ();
         while (alternative != null) {
-            str.append_printf ("%s(%%1$s),", alternative);
+            if (alternative.has_prefix ("?")) {
+                str.append (alternative);
+            } else {
+                str.append_printf ("%s(%%1$s),", alternative);
+            }
             alternative = list.arg ();
         }