Restructure some code.

No functional change, but leave the BLPOP'ing to the Queue, as the
queues know how to pop themselves.

rq/exceptions.py

@@ -0,0 +1,5 @@
+class NoQueueError(Exception):
+    pass
+
+class NoMoreWorkError(Exception):
+    pass

rq/queue.py

@@ -1,7 +1,7 @@
 import uuid
 from pickle import loads, dumps
 from .proxy import conn
-
+from .exceptions import NoMoreWorkError
 
 class DelayedResult(object):
     def __init__(self, key):
@@ -18,7 +18,6 @@ class DelayedResult(object):
         return self._rv
 
 
-
 def to_queue_key(queue_name):
     return 'rq:%s' % (queue_name,)
 
@@ -56,5 +55,28 @@ class Queue(object):
         s = conn.lpop(self.key)
         return loads(s)
 
+    @classmethod
+    def _dequeue_any(cls, queues):
+        # Redis' BLPOP command takes multiple queue arguments, but LPOP can
+        # only take a single queue.  Therefore, we need to loop over all
+        # queues manually, in order, and return None if no more work is
+        # available
+        for queue in queues:
+            value = conn.lpop(queue)
+            if value is not None:
+                return (queue, value)
+        return None
+
+    @classmethod
+    def dequeue_any(cls, queues, blocking):
+        if blocking:
+            queue, msg = conn.blpop(queues)
+        else:
+            value = cls._dequeue_any(queues)
+            if value is None:
+                raise NoMoreWorkError('No more work.')
+            queue, msg = value
+        return (queue, msg)
+
     def __str__(self):
         return self.name

rq/worker.py

@@ -10,13 +10,11 @@ except ImportError:
 from pickle import loads, dumps
 from .queue import Queue
 from .proxy import conn
+from .exceptions import NoMoreWorkError, NoQueueError
 
 def iterable(x):
     return hasattr(x, '__iter__')
 
-class NoQueueError(Exception): pass
-class NoMoreWorkError(Exception): pass
-
 class Worker(object):
     def __init__(self, queues, rv_ttl=500):
         if isinstance(queues, Queue):
@@ -57,35 +55,13 @@ class Worker(object):
         procname.setprocname('rq: %s' % (message,))
 
 
-    def multi_lpop(self, queues):
-        # Redis' BLPOP command takes multiple queue arguments, but LPOP can
-        # only take a single queue.  Therefore, we need to loop over all
-        # queues manually, in order, and raise an exception is no more work
-        # is available
-        for queue in queues:
-            value = conn.lpop(queue)
-            if value is not None:
-                return (queue, value)
-        return None
-
-    def pop_next_job(self, blocking):
-        queues = self.queue_keys()
-        if blocking:
-            queue, msg = conn.blpop(queues)
-        else:
-            value = self.multi_lpop(queues)
-            if value is None:
-                raise NoMoreWorkError('No more work.')
-            queue, msg = value
-        return (queue, msg)
-
     def _work(self, quit_when_done=False):
         did_work = False
         while True:
             self.procline('Waiting on %s' % (', '.join(self.queue_names()),))
             try:
                 wait_for_job = not quit_when_done
-                queue, msg = self.pop_next_job(wait_for_job)
+                queue, msg = Queue.dequeue_any(self.queues, wait_for_job)
                 did_work = True
             except NoMoreWorkError:
                 break