[tracker/wip/carlosg/tracker-3.0-api-breaks: 27/56] libtracker-sparql: Proxy database changes through endpoint GraphUpdated

[Carlos Garnacho <carlosg src gnome org>]

commit 1ae9e1b8254dcffc56162e24950a6bac29af3030
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Dec 22 12:08:40 2019 +0100

    libtracker-sparql: Proxy database changes through endpoint GraphUpdated
    
    This internally connects a TrackerNotifier, which ::event signal is
    serialized into the DBus signal we emit.

 src/libtracker-sparql/tracker-endpoint-dbus.c | 59 +++++++++++++++++++++++++--
 src/libtracker-sparql/tracker-notifier.c      |  4 +-
 2 files changed, 58 insertions(+), 5 deletions(-)
---
diff --git a/src/libtracker-sparql/tracker-endpoint-dbus.c b/src/libtracker-sparql/tracker-endpoint-dbus.c
index 00307a9c0..80b34dbe9 100644
--- a/src/libtracker-sparql/tracker-endpoint-dbus.c
+++ b/src/libtracker-sparql/tracker-endpoint-dbus.c
@@ -46,8 +46,8 @@ static const gchar introspection_xml[] =
        "      <arg type='h' name='input_stream' direction='in' />"
        "      <arg type='aaa{ss}' name='result' direction='out' />"
        "    </method>"
-       "    <signal name='GraphUpdate'>"
-       "      <arg type='sa(ii)' name='updates' />"
+       "    <signal name='GraphUpdated'>"
+       "      <arg type='sa{ii}' name='updates' />"
        "    </signal>"
        "  </interface>"
        "</node>";
@@ -66,6 +66,7 @@ struct _TrackerEndpointDBus {
        guint register_id;
        GDBusNodeInfo *node_info;
        GCancellable *cancellable;
+       TrackerNotifier *notifier;
 };
 
 typedef struct {
@@ -452,12 +453,54 @@ endpoint_dbus_iface_method_call (GDBusConnection       *connection,
        }
 }
 
+static void
+notifier_events_cb (TrackerNotifier *notifier,
+                    const gchar     *service,
+                    const gchar     *graph,
+                    GPtrArray       *events,
+                    gpointer         user_data)
+{
+       TrackerEndpointDBus *endpoint_dbus = user_data;
+       GVariantBuilder builder;
+       GError *error = NULL;
+       gint i;
+
+       g_variant_builder_init (&builder, G_VARIANT_TYPE ("(sa{ii})"));
+       g_variant_builder_add (&builder, "s", graph ? graph : "");
+       g_variant_builder_open (&builder, G_VARIANT_TYPE ("a{ii}"));
+
+       for (i = 0; i < events->len; i++) {
+               TrackerNotifierEvent *event;
+               gint event_type, id;
+
+               event = g_ptr_array_index (events, i);
+               event_type = tracker_notifier_event_get_event_type (event);
+               id = tracker_notifier_event_get_id (event);
+               g_variant_builder_add (&builder, "{ii}", event_type, id);
+       }
+
+       g_variant_builder_close (&builder);
+
+       if (!g_dbus_connection_emit_signal (endpoint_dbus->dbus_connection,
+                                           NULL,
+                                           endpoint_dbus->object_path,
+                                           "org.freedesktop.Tracker1.Endpoint",
+                                           "GraphUpdated",
+                                           g_variant_builder_end (&builder),
+                                           &error)) {
+               g_warning ("Could not emit GraphUpdated signal: %s", error->message);
+               g_error_free (error);
+       }
+}
+
 static gboolean
 tracker_endpoint_dbus_initable_init (GInitable     *initable,
                                      GCancellable  *cancellable,
                                      GError       **error)
 {
-       TrackerEndpointDBus *endpoint_dbus = TRACKER_ENDPOINT_DBUS (initable);
+       TrackerEndpoint *endpoint = TRACKER_ENDPOINT (initable);
+       TrackerEndpointDBus *endpoint_dbus = TRACKER_ENDPOINT_DBUS (endpoint);
+       TrackerSparqlConnection *conn;
 
        endpoint_dbus->node_info = g_dbus_node_info_new_for_xml (introspection_xml,
                                                                 error);
@@ -476,6 +519,12 @@ tracker_endpoint_dbus_initable_init (GInitable     *initable,
                                                   endpoint_dbus,
                                                   NULL,
                                                   error);
+
+       conn = tracker_endpoint_get_sparql_connection (endpoint);
+       endpoint_dbus->notifier = tracker_sparql_connection_create_notifier (conn, 0);
+       g_signal_connect (endpoint_dbus->notifier, "events",
+                         G_CALLBACK (notifier_events_cb), endpoint);
+
        return TRUE;
 }
 
@@ -498,6 +547,7 @@ tracker_endpoint_dbus_finalize (GObject *object)
                endpoint_dbus->register_id = 0;
        }
 
+       g_clear_object (&endpoint_dbus->notifier);
        g_clear_object (&endpoint_dbus->cancellable);
        g_clear_object (&endpoint_dbus->dbus_connection);
        g_clear_pointer (&endpoint_dbus->object_path, g_free);
@@ -591,6 +641,9 @@ tracker_endpoint_dbus_new (TrackerSparqlConnection  *sparql_connection,
        g_return_val_if_fail (!cancellable || G_IS_CANCELLABLE (cancellable), NULL);
        g_return_val_if_fail (!error || !*error, NULL);
 
+       if (!object_path)
+               object_path = "/org/freedesktop/Tracker1/Endpoint";
+
        return g_initable_new (TRACKER_TYPE_ENDPOINT_DBUS, cancellable, error,
                               "dbus-connection", dbus_connection,
                               "sparql-connection", sparql_connection,
diff --git a/src/libtracker-sparql/tracker-notifier.c b/src/libtracker-sparql/tracker-notifier.c
index 2ee9e2d63..e7f5f8b01 100644
--- a/src/libtracker-sparql/tracker-notifier.c
+++ b/src/libtracker-sparql/tracker-notifier.c
@@ -251,7 +251,7 @@ handle_events (TrackerNotifier           *notifier,
 {
        gint32 type, resource;
 
-       while (g_variant_iter_loop (iter, "(ii)", &type, &resource))
+       while (g_variant_iter_loop (iter, "{ii}", &type, &resource))
                _tracker_notifier_event_cache_push_event (cache, resource, type);
 }
 
@@ -424,7 +424,7 @@ graph_updated_cb (GDBusConnection *connection,
        const gchar *graph;
        gchar *service;
 
-       g_variant_get (parameters, "(&sa(ii))", &graph, &events);
+       g_variant_get (parameters, "(sa{ii})", &graph, &events);
 
        service = g_strdup_printf ("dbus:%s", sender_name);
        cache = _tracker_notifier_event_cache_new (notifier, sender_name, graph);