Allow instance methods to be enqueued

Only works for picklable instances

rq/job.py

@@ -1,4 +1,5 @@
 import importlib
+import inspect
 import times
 from uuid import uuid4
 from cPickle import loads, dumps, UnpicklingError
@@ -50,7 +51,11 @@ class Job(object):
         """
         connection = kwargs.pop('connection', None)
         job = cls(connection=connection)
-        job._func_name = '%s.%s' % (func.__module__, func.__name__)
+        if inspect.ismethod(func):
+            job._instance = func.im_self
+            job._func_name = func.__name__
+        else:
+            job._func_name = '%s.%s' % (func.__module__, func.__name__)
         job._args = args
         job._kwargs = kwargs
         job.description = job.get_call_string()
@@ -66,10 +71,17 @@ class Job(object):
         if func_name is None:
             return None
 
+        if self.instance:
+            return getattr(self.instance, func_name)
+
         module_name, func_name = func_name.rsplit('.', 1)
         module = importlib.import_module(module_name)
         return getattr(module, func_name)
 
+    @property
+    def instance(self):
+        return self._instance
+
     @property
     def args(self):
         return self._args
@@ -100,6 +112,7 @@ class Job(object):
         self._id = id
         self.created_at = times.now()
         self._func_name = None
+        self._instance = None
         self._args = None
         self._kwargs = None
         self.description = None
@@ -141,7 +154,7 @@ class Job(object):
     def job_tuple(self):
         """Returns the job tuple that encodes the actual function call that
         this job represents."""
-        return (self.func_name, self.args, self.kwargs)
+        return (self.func_name, self.instance, self.args, self.kwargs)
 
     @property
     def return_value(self):
@@ -190,7 +203,7 @@ class Job(object):
             else:
                 return times.to_universal(date_str)
 
-        self._func_name, self._args, self._kwargs = unpickle(data)
+        self._func_name, self._instance, self._args, self._kwargs = unpickle(data)
         self.created_at = to_date(created_at)
         self.origin = origin
         self.description = description

tests/fixtures.py

@@ -39,3 +39,12 @@ def create_file(path):
 def create_file_after_timeout(path, timeout):
     time.sleep(timeout)
     create_file(path)
+
+
+class Calculator(object):
+    """Test instance methods."""
+    def __init__(self, denominator):
+        self.denominator = denominator
+
+    def calculate(x, y):
+        return x * y / self.denominator

tests/test_job.py

@@ -1,7 +1,7 @@
 import times
 from datetime import datetime
 from tests import RQTestCase
-from tests.fixtures import some_calculation, say_hello
+from tests.fixtures import Calculator, some_calculation, say_hello
 from tests.helpers import strip_milliseconds
 from cPickle import loads
 from rq.job import Job
@@ -19,6 +19,7 @@ class TestJob(RQTestCase):
 
         # ...and nothing else
         self.assertIsNone(job.func)
+        self.assertIsNone(job.instance)
         self.assertIsNone(job.args)
         self.assertIsNone(job.kwargs)
         self.assertIsNone(job.origin)
@@ -35,6 +36,7 @@ class TestJob(RQTestCase):
         self.assertIsNotNone(job.id)
         self.assertIsNotNone(job.created_at)
         self.assertIsNotNone(job.description)
+        self.assertIsNone(job.instance)
 
         # Job data is set...
         self.assertEquals(job.func, some_calculation)
@@ -46,6 +48,15 @@ class TestJob(RQTestCase):
         self.assertIsNone(job.enqueued_at)
         self.assertIsNone(job.return_value)
 
+    def test_create_instance_method_job(self):
+        """Creation of jobs for instance methods."""
+        c = Calculator(2)
+        job = Job.create(c.calculate, 3, 4)
+
+        # Job data is set
+        self.assertEquals(job.func, c.calculate)
+        self.assertEquals(job.instance, c)
+        self.assertEquals(job.args, (3, 4))
 
     def test_save(self):  # noqa
         """Storing jobs."""
@@ -64,7 +75,7 @@ class TestJob(RQTestCase):
         """Fetching jobs."""
         # Prepare test
         self.testconn.hset('rq:job:some_id', 'data',
-                "(S'tests.fixtures.some_calculation'\np0\n(I3\nI4\ntp1\n(dp2\nS'z'\np3\nI2\nstp4\n.")  # noqa
+                "(S'tests.fixtures.some_calculation'\nN(I3\nI4\nt(dp1\nS'z'\nI2\nstp2\n.")  # noqa
         self.testconn.hset('rq:job:some_id', 'created_at',
                 "2012-02-07 22:13:24+0000")
 
@@ -72,6 +83,7 @@ class TestJob(RQTestCase):
         job = Job.fetch('some_id')
         self.assertEquals(job.id, 'some_id')
         self.assertEquals(job.func_name, 'tests.fixtures.some_calculation')
+        self.assertIsNone(job.instance)
         self.assertEquals(job.args, (3, 4))
         self.assertEquals(job.kwargs, dict(z=2))
         self.assertEquals(job.created_at, datetime(2012, 2, 7, 22, 13, 24))

tests/test_queue.py

@@ -1,5 +1,5 @@
 from tests import RQTestCase
-from tests.fixtures import say_hello, div_by_zero
+from tests.fixtures import Calculator, say_hello, div_by_zero
 from rq import Queue, get_failed_queue
 from rq.job import Job
 from rq.exceptions import InvalidJobOperationError
@@ -132,6 +132,19 @@ class TestQueue(RQTestCase):
         # ...and assert the queue count when down
         self.assertEquals(q.count, 0)
 
+    def test_dequeue_instance_method(self):
+        """Dequeueing instance method jobs from queues."""
+        q = Queue()
+        c = Calculator(2)
+        result = q.enqueue(c.calculate, 3, 4)
+
+        job = q.dequeue()
+        # The instance has been pickled and unpickled, so it is now a separate
+        # object. Test for equality using each object's __dict__ instead.
+        self.assertEquals(job.instance.__dict__, c.__dict__)
+        self.assertEquals(job.func.__name__, 'calculate')
+        self.assertEquals(job.args, (3, 4))
+
     def test_dequeue_ignores_nonexisting_jobs(self):
         """Dequeuing silently ignores non-existing jobs."""