[gnome-photos/sam/tracker3] Use TrackerNotifier to monitor for local changes

[Sam Thursfield <sthursfield src gnome org>]

commit 121695cb3c7e88d0c88c0af5bfd7fec5356a8f8c
Author: Sam Thursfield <sam afuera me uk>
Date:   Sun Aug 2 15:57:42 2020 +0200

    Use TrackerNotifier to monitor for local changes
    
    Closes https://gitlab.gnome.org/GNOME/gnome-photos/-/issues/59

 src/meson.build                     |  12 -
 src/photos-item-manager.c           |  56 +++--
 src/photos-tracker-change-event.c   | 136 -----------
 src/photos-tracker-change-event.h   |  64 -----
 src/photos-tracker-change-monitor.c | 468 ------------------------------------
 src/photos-tracker-change-monitor.h |  42 ----
 src/photos-tracker-queue.c          |  65 +++--
 src/photos-tracker-queue.h          |   2 +
 src/photos-tracker-resources.xml    |  31 ---
 9 files changed, 63 insertions(+), 813 deletions(-)
---
diff --git a/src/meson.build b/src/meson.build
index eb538a87..fef9f759 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -118,8 +118,6 @@ sources = files(
   'photos-tool-filter-button.c',
   'photos-tool-filters.c',
   'photos-tool.c',
-  'photos-tracker-change-event.c',
-  'photos-tracker-change-monitor.c',
   'photos-tracker-collection-view-controller.c',
   'photos-tracker-collections-controller.c',
   'photos-tracker-controller.c',
@@ -340,16 +338,6 @@ sources += gnome.gdbus_codegen(
   autocleanup: 'all',
 )
 
-tracker_resources = 'photos-tracker-resources'
-
-sources += gnome.gdbus_codegen(
-  tracker_resources,
-  tracker_resources + '.xml',
-  interface_prefix: 'org.freedesktop.Tracker3.',
-  namespace: 'Tracker',
-  autocleanup: 'all',
-)
-
 cflags = [
   '-DPACKAGE_LIBEXEC_DIR="@0@"'.format(photos_libexecdir),
   '-DPACKAGE_LOCALE_DIR="@0@"'.format(photos_localedir),
diff --git a/src/photos-item-manager.c b/src/photos-item-manager.c
index a431ebb7..549606e5 100644
--- a/src/photos-item-manager.c
+++ b/src/photos-item-manager.c
@@ -41,8 +41,6 @@
 #include "photos-query.h"
 #include "photos-search-context.h"
 #include "photos-single-item-job.h"
-#include "photos-tracker-change-event.h"
-#include "photos-tracker-change-monitor.h"
 #include "photos-tracker-queue.h"
 #include "photos-utils.h"
 
@@ -60,7 +58,7 @@ struct _PhotosItemManager
   PhotosBaseItem *active_collection;
   PhotosBaseManager **item_mngr_chldrn;
   PhotosLoadState load_state;
-  PhotosTrackerChangeMonitor *monitor;
+  TrackerNotifier *notifier;
   PhotosTrackerQueue *queue;
   PhotosWindowMode mode;
   gboolean fullscreen;
@@ -529,21 +527,23 @@ photos_item_manager_item_created (PhotosItemManager *self, const gchar *urn)
 
 
 static void
-photos_item_manager_changes_pending_foreach (gpointer key, gpointer value, gpointer user_data)
+photos_item_manager_changes_pending_foreach (gpointer data,
+                                             gpointer user_data)
 {
   PhotosItemManager *self = PHOTOS_ITEM_MANAGER (user_data);
-  PhotosTrackerChangeEvent *change_event = (PhotosTrackerChangeEvent *) value;
-  PhotosTrackerChangeEventType change_type;
+  TrackerNotifierEvent *event = (TrackerNotifierEvent *) data;
+  TrackerNotifierEventType change_type;
   const gchar *change_urn;
 
-  change_type = photos_tracker_change_event_get_type (change_event);
-  change_urn = photos_tracker_change_event_get_urn (change_event);
+  change_type = tracker_notifier_event_get_event_type (event);
+  change_urn = tracker_notifier_event_get_urn (event);
 
-  if (change_type == PHOTOS_TRACKER_CHANGE_EVENT_CHANGED)
+  if (change_type == TRACKER_NOTIFIER_EVENT_UPDATE)
     {
       GObject *object;
 
       object = photos_base_manager_get_object_by_id (PHOTOS_BASE_MANAGER (self), change_urn);
+      g_message ("UPDATE event for %s, object %p", change_urn, object);
       if (object != NULL)
         {
           photos_base_item_refresh (PHOTOS_BASE_ITEM (object));
@@ -557,15 +557,17 @@ photos_item_manager_changes_pending_foreach (gpointer key, gpointer value, gpoin
             }
         }
     }
-  else if (change_type == PHOTOS_TRACKER_CHANGE_EVENT_CREATED)
+  else if (change_type == TRACKER_NOTIFIER_EVENT_CREATE)
     {
+      g_message ("CREATE event for %s", change_urn);
       photos_item_manager_item_created (self, change_urn);
     }
-  else if (change_type == PHOTOS_TRACKER_CHANGE_EVENT_DELETED)
+  else if (change_type == TRACKER_NOTIFIER_EVENT_DELETE)
     {
       GObject *object;
 
       object = photos_base_manager_get_object_by_id (PHOTOS_BASE_MANAGER (self), change_urn);
+      g_message ("DELETE event for %s, object %p", change_urn, object);
       if (object != NULL)
         {
           photos_base_item_destroy (PHOTOS_BASE_ITEM (object));
@@ -577,9 +579,13 @@ photos_item_manager_changes_pending_foreach (gpointer key, gpointer value, gpoin
 
 
 static void
-photos_item_manager_changes_pending (PhotosItemManager *self, GHashTable *changes)
+photos_item_manager_changes_pending (PhotosItemManager *self,
+                                     const gchar       *service,
+                                     const gchar       *graph,
+                                     GPtrArray         *events,
+                                     gpointer           user_data)
 {
-  g_hash_table_foreach (changes, photos_item_manager_changes_pending_foreach, self);
+  g_ptr_array_foreach (events, photos_item_manager_changes_pending_foreach, self);
 }
 
 
@@ -1038,7 +1044,7 @@ photos_item_manager_dispose (GObject *object)
   g_clear_object (&self->active_object);
   g_clear_object (&self->loader_cancellable);
   g_clear_object (&self->active_collection);
-  g_clear_object (&self->monitor);
+  g_clear_object (&self->notifier);
   g_clear_object (&self->queue);
 
   G_OBJECT_CLASS (photos_item_manager_parent_class)->dispose (object);
@@ -1093,20 +1099,24 @@ photos_item_manager_init (PhotosItemManager *self)
 
   self->mode = PHOTOS_WINDOW_MODE_NONE;
 
-  self->monitor = photos_tracker_change_monitor_dup_singleton (NULL, NULL);
-  if (G_LIKELY (self->monitor != NULL))
-    g_signal_connect_object (self->monitor,
-                             "changes-pending",
-                             G_CALLBACK (photos_item_manager_changes_pending),
-                             self,
-                             G_CONNECT_SWAPPED);
-
   {
     g_autoptr (GError) error = NULL;
 
     self->queue = photos_tracker_queue_dup_singleton (NULL, &error);
     if (G_UNLIKELY (error != NULL))
-      g_warning ("Unable to create PhotosTrackerQueue: %s", error->message);
+      {
+        g_warning ("Unable to create PhotosTrackerQueue: %s", error->message);
+        self->notifier = NULL;
+      }
+    else
+      {
+        self->notifier = photos_tracker_queue_get_notifier (self->queue);
+        g_signal_connect_object (self->notifier,
+                                 "events",
+                                 G_CALLBACK (photos_item_manager_changes_pending),
+                                 self,
+                                 G_CONNECT_SWAPPED);
+      }
   }
 
   self->fullscreen = FALSE;
diff --git a/src/photos-tracker-queue.c b/src/photos-tracker-queue.c
index 32e3fb18..83f1b181 100644
--- a/src/photos-tracker-queue.c
+++ b/src/photos-tracker-queue.c
@@ -37,7 +37,8 @@ struct _PhotosTrackerQueue
   GObject parent_instance;
   GError *initialization_error;
   GQueue *queue;
-  TrackerSparqlConnection *connection;
+  TrackerSparqlConnection *local_connection;
+  TrackerSparqlConnection *miner_fs_connection;
   gboolean is_initialized;
   gboolean running;
   gboolean miner_fs_ready;
@@ -187,7 +188,7 @@ photos_tracker_queue_check (PhotosTrackerQueue *self)
   switch (data->query_type)
     {
     case PHOTOS_TRACKER_QUERY_SELECT:
-      tracker_sparql_connection_query_async (self->connection,
+      tracker_sparql_connection_query_async (self->local_connection,
                                              sparql,
                                              data->cancellable,
                                              photos_tracker_queue_collector,
@@ -195,7 +196,7 @@ photos_tracker_queue_check (PhotosTrackerQueue *self)
       break;
 
     case PHOTOS_TRACKER_QUERY_UPDATE:
-      tracker_sparql_connection_update_async (self->connection,
+      tracker_sparql_connection_update_async (self->local_connection,
                                               sparql,
                                               data->cancellable,
                                               photos_tracker_queue_collector,
@@ -203,7 +204,7 @@ photos_tracker_queue_check (PhotosTrackerQueue *self)
       break;
 
     case PHOTOS_TRACKER_QUERY_UPDATE_BLANK:
-      tracker_sparql_connection_update_blank_async (self->connection,
+      tracker_sparql_connection_update_blank_async (self->local_connection,
                                                     sparql,
                                                     data->cancellable,
                                                     photos_tracker_queue_collector,
@@ -219,13 +220,12 @@ photos_tracker_queue_check (PhotosTrackerQueue *self)
 static const gchar *
 photos_tracker_queue_start_session_miner_fs (PhotosTrackerQueue *self, GError **error)
 {
-  g_autoptr(TrackerSparqlConnection) miner_fs = NULL;
   const gchar *busname = "org.freedesktop.Tracker3.Miner.Files";
 
-  miner_fs = tracker_sparql_connection_bus_new (busname, NULL, NULL, error);
+  photos_debug (PHOTOS_DEBUG_TRACKER, "Connecting to %s", busname);
+  self->miner_fs_connection = tracker_sparql_connection_bus_new (busname, NULL, NULL, error);
   if (*error)
     {
-      /* Creating the connection should always succeed, so this is weird. */
       g_warning ("Unable to create connection for session-wide Tracker indexer: %s", (*error)->message);
       return NULL;
     }
@@ -236,30 +236,10 @@ photos_tracker_queue_start_session_miner_fs (PhotosTrackerQueue *self, GError **
 static const gchar *
 photos_tracker_queue_start_local_miner_fs (PhotosTrackerQueue *self, GError **error)
 {
-  GDBusConnection *bus;
   const gchar *busname = "org.gnome.Photos.Tracker3.Miner.Files";
 
-  bus = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, error);
-
-  if (*error)
-    {
-      g_critical ("Could not connect to session bus: %s", (*error)->message);
-      return NULL;
-    }
-
-  photos_debug (PHOTOS_DEBUG_TRACKER, "Contacting %s", busname);
-  g_dbus_connection_call_sync (bus,
-                               busname,
-                               "/org/freedesktop/Tracker3/Miner/Files",
-                               "org.freedesktop.DBus.Peer",
-                               "Ping",
-                               NULL,
-                               NULL,
-                               G_DBUS_CALL_FLAGS_NONE,
-                               5000, /* Startup timeout for miner-fs in msec */
-                               NULL,
-                               error);
-
+  photos_debug (PHOTOS_DEBUG_TRACKER, "Connecting to %s", busname);
+  self->miner_fs_connection = tracker_sparql_connection_bus_new (busname, NULL, NULL, error);
   if (*error)
     {
       g_critical ("Could not start local Tracker indexer at %s: %s", busname, (*error)->message);
@@ -298,7 +278,8 @@ photos_tracker_queue_dispose (GObject *object)
 {
   PhotosTrackerQueue *self = PHOTOS_TRACKER_QUEUE (object);
 
-  g_clear_object (&self->connection);
+  g_clear_object (&self->local_connection);
+  g_clear_object (&self->miner_fs_connection);
 
   G_OBJECT_CLASS (photos_tracker_queue_parent_class)->dispose (object);
 }
@@ -396,7 +377,7 @@ photos_tracker_queue_initable_init (GInitable *initable, GCancellable *cancellab
 
   if (self->is_initialized)
     {
-      if (self->connection != NULL)
+      if (self->local_connection != NULL && self->miner_fs_connection != NULL)
         ret_val = TRUE;
       else
         g_assert_nonnull (self->initialization_error);
@@ -418,11 +399,11 @@ photos_tracker_queue_initable_init (GInitable *initable, GCancellable *cancellab
   store = g_file_new_build_filename (g_get_user_data_dir (), "gnome-photos", NULL);
 
   photos_debug (PHOTOS_DEBUG_TRACKER, "Opening local database at %s", g_file_peek_path (store));
-  self->connection = tracker_sparql_connection_new (tracker_flags,
-                                                    store,
-                                                    tracker_sparql_get_ontology_nepomuk (),
-                                                    cancellable,
-                                                    &self->initialization_error);
+  self->local_connection = tracker_sparql_connection_new (tracker_flags,
+                                                          store,
+                                                          tracker_sparql_get_ontology_nepomuk (),
+                                                          cancellable,
+                                                          &self->initialization_error);
 
   if (G_UNLIKELY (self->initialization_error != NULL))
     goto out;
@@ -444,7 +425,8 @@ photos_tracker_queue_initable_init (GInitable *initable, GCancellable *cancellab
   else
     {
       photos_debug (PHOTOS_DEBUG_TRACKER, "Initialization failed due to %s", 
self->initialization_error->message);
-      g_clear_object (&self->connection);
+      g_clear_object (&self->miner_fs_connection);
+      g_clear_object (&self->local_connection);
       ret_val = FALSE;
     }
 
@@ -493,6 +475,15 @@ photos_tracker_queue_get_miner_fs_busname (PhotosTrackerQueue *self)
   return self->miner_fs_busname;
 }
 
+TrackerNotifier *
+photos_tracker_queue_get_notifier (PhotosTrackerQueue *self)
+{
+  /* We want notifications on filesystem changes, we don't need them for the
+   * local database which we manage ourselves.
+   */
+  return tracker_sparql_connection_create_notifier (self->miner_fs_connection);
+}
+
 void
 photos_tracker_queue_select (PhotosTrackerQueue *self,
                              PhotosQuery *query,
diff --git a/src/photos-tracker-queue.h b/src/photos-tracker-queue.h
index 2a7118fc..20a62e26 100644
--- a/src/photos-tracker-queue.h
+++ b/src/photos-tracker-queue.h
@@ -24,6 +24,7 @@
 #define PHOTOS_TRACKER_QUEUE_H
 
 #include <gio/gio.h>
+#include <libtracker-sparql/tracker-sparql.h>
 
 #include "photos-query.h"
 
@@ -35,6 +36,7 @@ G_DECLARE_FINAL_TYPE (PhotosTrackerQueue, photos_tracker_queue, PHOTOS, TRACKER_
 PhotosTrackerQueue    *photos_tracker_queue_dup_singleton          (GCancellable *cancellable, GError 
**error);
 
 const gchar *          photos_tracker_queue_get_miner_fs_busname   (PhotosTrackerQueue *self);
+TrackerNotifier *      photos_tracker_queue_get_notifier           (PhotosTrackerQueue *self);
 
 void                   photos_tracker_queue_select                 (PhotosTrackerQueue *self,
                                                                     PhotosQuery *query,