Terminology change: waitlist -> dependents.

rq/job.py

@@ -232,9 +232,9 @@ class Job(object):
         return b'rq:job:' + job_id.encode('utf-8')
 
     @classmethod
-    def waitlist_key_for(cls, job_id):
+    def dependents_key_for(cls, job_id):
         """The Redis key that is used to store job hash under."""
-        return 'rq:job:%s:waitlist' % (job_id,)
+        return 'rq:job:%s:dependents' % (job_id,)
 
     @property
     def key(self):
@@ -242,9 +242,9 @@ class Job(object):
         return self.key_for(self.id)
 
     @property
-    def waitlist_key(self):
+    def dependents_key(self):
         """The Redis key that is used to store job hash under."""
-        return self.waitlist_key_for(self.id)
+        return self.dependents_key_for(self.id)
 
     @property  # noqa
     def job_tuple(self):
@@ -422,16 +422,17 @@ class Job(object):
             connection.expire(self.key, ttl)
 
     def register_dependency(self):
-        """Jobs may have a waitlist. Jobs in this waitlist are enqueued
-        only if the dependency job is successfully performed. We maintain this
-        waitlist in a Redis set, with key that looks something like:
-            
-            rq:job:job_id:waitlist = {'job_id_1', 'job_id_2'}
-        
-        This method puts the job on it's dependency's waitlist.
+        """Jobs may have dependencies. Jobs are enqueued only if the job they
+        depend on is successfully performed. We record this relation as
+        a reverse dependency (a Redis set), with a key that looks something
+        like:
+
+            rq:job:job_id:dependents = {'job_id_1', 'job_id_2'}
+
+        This method adds the current job in its dependency's dependents set.
         """
         # TODO: This can probably be pipelined
-        self.connection.sadd(Job.waitlist_key_for(self._dependency_id), self.id)
+        self.connection.sadd(Job.dependents_key_for(self._dependency_id), self.id)
 
     def __str__(self):
         return '<Job %s: %s>' % (self.id, self.description)

rq/queue.py

@@ -156,7 +156,7 @@ class Queue(object):
                          description=description, depends_on=depends_on)
 
         # If job depends on an unfinished job, register itself on it's
-        # parent's waitlist instead of enqueueing it.
+        # parent's dependents instead of enqueueing it.
         # If WatchError is raised in the process, that means something else is
         # modifying the dependency. In this case we simply retry
         if depends_on is not None:
@@ -243,15 +243,15 @@ class Queue(object):
             job.save()
         return job
 
-    def enqueue_waitlist(self, job):
-        """Enqueues all jobs in the waitlist and clears it"""
+    def enqueue_dependents(self, job):
+        """Enqueues all jobs in the given job's dependents set and clears it."""
         # TODO: can probably be pipelined
         while True:
-            job_id = as_text(self.connection.spop(job.waitlist_key))
+            job_id = as_text(self.connection.spop(job.dependents_key))
             if job_id is None:
                 break
-            waitlisted_job = Job.fetch(job_id, connection=self.connection)
-            self.enqueue_job(waitlisted_job)
+            dependent = Job.fetch(job_id, connection=self.connection)
+            self.enqueue_job(dependent)
 
     def pop_job_id(self):
         """Pops a given job ID from this Redis queue."""

rq/worker.py

@@ -327,7 +327,7 @@ class Worker(object):
                 self.fork_and_perform_job(job)
                 self.connection.expire(self.key, self.default_worker_ttl)
                 if job.status == 'finished':
-                    queue.enqueue_waitlist(job)
+                    queue.enqueue_dependents(job)
 
                 did_perform_work = True
         finally:

tests/test_job.py

@@ -284,9 +284,9 @@ class TestJob(RQTestCase):
         self.assertRaises(NoSuchJobError, Job.fetch, job.id, self.testconn)
 
     def test_register_dependency(self):
-        """Test that jobs updates the correct job waitlist"""
+        """Test that jobs updates the correct job dependents."""
         job = Job.create(func=say_hello)
         job._dependency_id = 'id'
         job.save()
         job.register_dependency()
-        self.assertEqual(as_text(self.testconn.spop('rq:job:id:waitlist')), job.id)
+        self.assertEqual(as_text(self.testconn.spop('rq:job:id:dependents')), job.id)

tests/test_queue.py

@@ -289,8 +289,8 @@ class TestQueue(RQTestCase):
         # Queue.all() should still report the empty queues
         self.assertEquals(len(Queue.all()), 3)
 
-    def test_enqueue_waitlist(self):
-        """Enqueueing a waitlist pushes all jobs in waitlist to queue"""
+    def test_enqueue_dependents(self):
+        """Enqueueing the dependent jobs pushes all jobs in the depends set to the queue."""
         q = Queue()
         parent_job = Job.create(func=say_hello)
         parent_job.save()
@@ -301,11 +301,11 @@ class TestQueue(RQTestCase):
         job_2.save()
         job_2.register_dependency()
 
-        # After waitlist is enqueued, job_1 and job_2 should be in queue
+        # After dependents is enqueued, job_1 and job_2 should be in queue
         self.assertEqual(q.job_ids, [])
-        q.enqueue_waitlist(parent_job)
+        q.enqueue_dependents(parent_job)
         self.assertEqual(set(q.job_ids), set([job_1.id, job_2.id]))
-        self.assertFalse(self.testconn.exists(parent_job.waitlist_key))
+        self.assertFalse(self.testconn.exists(parent_job.dependents_key))
 
     def test_enqueue_job_with_dependency(self):
         """Jobs are enqueued only when their dependencies are finished"""

tests/test_worker.py

@@ -236,7 +236,7 @@ class TestWorker(RQTestCase):
         self.assertEqual(job.is_failed, True)
 
     def test_job_dependency(self):
-        """Enqueue waitlisted jobs only if their parents don't fail"""
+        """Enqueue dependent jobs only if their parents don't fail"""
         q = Queue()
         w = Worker([q])
         parent_job = q.enqueue(say_hello)