Merge pull request #1548 from croneter/fix-race

Fix a racing condition that could lead to the sync process getting stuck

resources/lib/backgroundthread.py

@@ -135,43 +135,6 @@ class ProcessingQueue(Queue.Queue, object):
     def _qsize(self):
         return self._current_queue._qsize() if self._current_queue else 0
 
-    def _total_qsize(self):
-        """
-        This method is BROKEN as it can lead to a deadlock when a single item
-        from the current section takes longer to download then any new items
-        coming in
-        """
-        return sum(q._qsize() for q in self._queues) if self._queues else 0
-
-    def put(self, item, block=True, timeout=None):
-        """
-        PKC customization of Queue.put. item needs to be the tuple
-            (count [int], {'section': [Section], 'xml': [etree xml]})
-        """
-        self.not_full.acquire()
-        try:
-            if self.maxsize > 0:
-                if not block:
-                    if self._qsize() == self.maxsize:
-                        raise Queue.Full
-                elif timeout is None:
-                    while self._qsize() == self.maxsize:
-                        self.not_full.wait()
-                elif timeout < 0:
-                    raise ValueError("'timeout' must be a non-negative number")
-                else:
-                    endtime = _time() + timeout
-                    while self._qsize() == self.maxsize:
-                        remaining = endtime - _time()
-                        if remaining <= 0.0:
-                            raise Queue.Full
-                        self.not_full.wait(remaining)
-            self._put(item)
-            self.unfinished_tasks += 1
-            self.not_empty.notify()
-        finally:
-            self.not_full.release()
-
     def _put(self, item):
         for i, section in enumerate(self._sections):
             if item[1]['section'] == section:
@@ -188,16 +151,13 @@ class ProcessingQueue(Queue.Queue, object):
         Once the get()-method returns None, you've received the sentinel and
         you've thus exhausted the queue
         """
-        self.not_full.acquire()
+        with self.not_full:
-        try:
             section.number_of_items = 1
             self._add_section(section)
             # Add the actual sentinel to the queue we just added
             self._queues[-1]._put((None, None))
             self.unfinished_tasks += 1
             self.not_empty.notify()
-        finally:
-            self.not_full.release()
 
     def add_section(self, section):
         """
@@ -207,11 +167,8 @@ class ProcessingQueue(Queue.Queue, object):
         Be sure to set section.number_of_items correctly as it will signal
         when processing is completely done for a specific section!
         """
-        self.mutex.acquire()
+        with self.mutex:
-        try:
             self._add_section(section)
-        finally:
-            self.mutex.release()
 
     def _add_section(self, section):
         self._sections.append(section)

resources/lib/library_sync/fill_metadata_queue.py

@@ -46,6 +46,10 @@ class FillMetadataQueue(common.LibrarySyncMixin,
                 if (not self.repair and
                         plexdb.checksum(plex_id, section.plex_type) == checksum):
                     continue
+                if not do_process_section:
+                    do_process_section = True
+                    self.processing_queue.add_section(section)
+                    LOG.debug('Put section in processing queue: %s', section)
                 try:
                     self.get_metadata_queue.put((count, plex_id, section),
                                                 timeout=QUEUE_TIMEOUT)
@@ -54,16 +58,13 @@ class FillMetadataQueue(common.LibrarySyncMixin,
                               'aborting sync now', plex_id)
                     section.sync_successful = False
                     break
+                else:
                     count += 1
-                if not do_process_section:
-                    do_process_section = True
-                    self.processing_queue.add_section(section)
-                    LOG.debug('Put section in queue with %s items: %s',
-                              section.number_of_items, section)
         # We might have received LESS items from the PMS than anticipated.
         # Ensures that our queues finish
-        LOG.debug('%s items to process for section %s', count, section)
         section.number_of_items = count
+        LOG.debug('%s items to process for section %s',
+                  section.number_of_items, section)
 
     def _run(self):
         while not self.should_cancel():

resources/lib/library_sync/sections.py

@@ -93,6 +93,7 @@ class Section(object):
                 "'name': '{self.name}', "
                 "'section_id': {self.section_id}, "
                 "'section_type': '{self.section_type}', "
+                "'plex_type': '{self.plex_type}', "
                 "'sync_to_kodi': {self.sync_to_kodi}, "
                 "'last_sync': {self.last_sync}"
                 "}}").format(self=self).encode('utf-8')