[gnome-music/wip/garnacho/performance-improvements: 4/5] albumArtCache: blacklist failed items on all exceptions

[Carlos Garnacho <carlosg src gnome org>]

commit aa5ecaabecb5941369b2d8591c835506e99abed7
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Feb 15 15:11:17 2015 +0100

    albumArtCache: blacklist failed items on all exceptions
    
    Blacklisting has moved to finish(), which has been ensured to be called
    on all error paths. items are also checked early in the blacklist on the
    lookup process.
    
    This, most notably, ensures we don't continuously spawn threads to look
    up items that previously failed, the worker/download threads will be
    spawn just once for each of these.

 gnomemusic/albumArtCache.py |   28 +++++++++++++++++++---------
 1 files changed, 19 insertions(+), 9 deletions(-)
---
diff --git a/gnomemusic/albumArtCache.py b/gnomemusic/albumArtCache.py
index 73eb19d..6bf984c 100644
--- a/gnomemusic/albumArtCache.py
+++ b/gnomemusic/albumArtCache.py
@@ -172,6 +172,10 @@ class AlbumArtCache:
 
     @log
     def lookup(self, item, width, height, callback, itr, artist, album):
+        if artist in self.blacklist and album in self.blacklist[artist]:
+            self.finish(item, None, None, callback, itr)
+            return
+
         try:
             # Make sure we don't lookup the same iterators several times
             with self.threading_lock:
@@ -206,12 +210,21 @@ class AlbumArtCache:
             width = width or -1
             height = height or -1
             pixbuf = GdkPixbuf.Pixbuf.new_from_file_at_scale(path, width, height, True)
-            self.finish(item, _make_icon_frame(pixbuf), path, callback, itr)
+            self.finish(item, _make_icon_frame(pixbuf), path, callback, itr, width, height)
         except Exception as e:
             logger.warn("Error: %s" % e)
 
     @log
-    def finish(self, item, pixbuf, path, callback, itr):
+    def finish(self, item, pixbuf, path, callback, itr, width=-1, height=-1, artist=None, album=None):
+        if (pixbuf is None and artist is not None):
+            # Blacklist artist-album combination
+            if artist not in self.blacklist:
+                self.blacklist[artist] = []
+            self.blacklist[artist].append(album)
+
+        if pixbuf is None:
+            pixbuf = self.get_default_icon(width, height, False)
+
         try:
             if path:
                 item.set_thumbnail(GLib.filename_to_uri(path, None))
@@ -232,6 +245,7 @@ class AlbumArtCache:
             self.thread_queue.put(t)
         except Exception as e:
             logger.warn("Error: %s" % e)
+            self.finish(item, None, None, callback, itr, width, height, artist, album)
 
     @log
     def album_art_for_item_callback(self, source, param, item, count, data, error):
@@ -242,20 +256,15 @@ class AlbumArtCache:
 
             uri = item.get_thumbnail()
             if uri is None:
-                # Blacklist artist-album combination
-                if artist not in self.blacklist:
-                    self.blacklist[artist] = []
-                self.blacklist[artist].append(album)
-
                 logger.warn("can't find artwork for album '%s' by %s" % (album, artist))
-                noArtworkIcon = self.get_default_icon(width, height, False)
-                self.finish(item, noArtworkIcon, None, callback, itr)
+                self.finish(item, None, None, callback, itr, width, height, artist, album)
                 return
 
             t = Thread(target=self.download_worker, args=(item, width, height, path, callback, itr, artist, 
album, uri))
             self.thread_queue.put(t)
         except Exception as e:
             logger.warn("Error: %s" % e)
+            self.finish(item, None, None, callback, itr, width, height, artist, album)
 
     @log
     def download_worker(self, item, width, height, path, callback, itr, artist, album, uri):
@@ -266,3 +275,4 @@ class AlbumArtCache:
             self.lookup_worker(item, width, height, callback, itr, artist, album)
         except Exception as e:
             logger.warn("Error: %s" % e)
+            self.finish(item, None, None, callback, itr, width, height, artist, album)