Make sure to disconnect from the database when finished with the processes

util/queueprocess.py

@@ -13,12 +13,13 @@ class QueueProcess(object):
   """ Helper class which invokes a worker in a process to produce
       data for one (or more) queues.
   """
-  def __init__(self, get_producer, chunk_size, max_size, args):
+  def __init__(self, get_producer, chunk_size, max_size, args, finished=None):
     self._get_producer = get_producer
     self._queues = []
     self._chunk_size = chunk_size
     self._max_size = max_size
     self._args = args or []
+    self._finished = finished
 
   def create_queue(self):
     """ Adds a multiprocessing queue to the list of queues. Any queues added
@@ -29,14 +30,21 @@ class QueueProcess(object):
     return queue
 
   @staticmethod
-  def run_process(target, args):
-    Process(target=target, args=args).start()
+  def run_process(target, args, finished=None):
+    def _target(tar, arg, fin):
+      try:
+        tar(*args)
+      finally:
+        if fin:
+          fin()
+
+    Process(target=_target, args=(target, args, finished)).start()
 
   def run(self):
     # Important! gipc is used here because normal multiprocessing does not work
     # correctly with gevent when we sleep.
     args = (self._get_producer, self._queues, self._chunk_size, self._args)
-    QueueProcess.run_process(_run, args)
+    QueueProcess.run_process(_run, args, finished=self._finished)
 
 def _run(get_producer, queues, chunk_size, args):
   producer = get_producer(*args)