Prevent exception on transcoding failure (bug 460)

Fix an unhandled exception when video fails to transcode for some
reason. Closes bug 460.

mediagoblin/media_types/video/processing.py

@@ -252,13 +252,15 @@ class CommonVideoProcessor(MediaProcessor):
         # metadata itself has container-related data in tags, like video-codec
         store_metadata(self.entry, metadata)
 
+        orig_dst_dimensions = (metadata.get_video_streams()[0].get_width(),
+                metadata.get_video_streams()[0].get_height())
+
         # Figure out whether or not we need to transcode this video or
         # if we can skip it
         if skip_transcode(metadata, medium_size):
             _log.debug('Skipping transcoding')
 
-            dst_dimensions = (metadata.get_video_streams()[0].get_width(),
-                    metadata.get_video_streams()[0].get_height())
+            dst_dimensions = orig_dst_dimensions
 
             # If there is an original and transcoded, delete the transcoded
             # since it must be of lower quality then the original
@@ -273,8 +275,10 @@ class CommonVideoProcessor(MediaProcessor):
                                       vorbis_quality=vorbis_quality,
                                       progress_callback=progress_callback,
                                       dimensions=tuple(medium_size))
+            if self.transcoder.dst_data:
                 video_info = self.transcoder.dst_data.get_video_streams()[0]
-            dst_dimensions = (video_info.get_width(), video_info.get_height())
+                dst_dimensions = (video_info.get_width(),
+                                  video_info.get_height())
                 self._keep_best()
 
                 # Push transcoded video to public storage
@@ -286,6 +290,8 @@ class CommonVideoProcessor(MediaProcessor):
                 self.entry.set_file_metadata('webm_video', **file_metadata)
 
                 self.did_transcode = True
+            else:
+                dst_dimensions = orig_dst_dimensions
 
         # Save the width and height of the transcoded video
         self.entry.media_data_init(

mediagoblin/media_types/video/transcoders.py

@@ -358,6 +358,7 @@ class VideoTranscoder(object):
                     _log.info('{percent}% done...'.format(percent=percent))
         elif message.type == Gst.MessageType.ERROR:
             _log.error('Got error: {0}'.format(message.parse_error()))
+            self.dst_data = None
             self.__stop()
 
     def __stop(self):