Resolve connections early.

Fixes #101.

rq/connections.py

@@ -51,6 +51,20 @@ def get_current_connection():
     return _connection_stack.top
 
 
+def resolve_connection(connection=None):
+    """Convenience function to resolve the given or the current connection.
+    Raises an exception if it cannot resolve a connection now.
+    """
+    if connection is not None:
+        return connection
+
+    connection = get_current_connection()
+    if connection is None:
+        raise NoRedisConnectionException(
+                'Could not resolve a Redis connection.')
+    return connection
+
+
 _connection_stack = LocalStack()
 
 __all__ = ['Connection',

rq/decorators.py

@@ -1,14 +1,15 @@
 from functools import wraps
 from .queue import Queue
+from .connections import resolve_connection
 
 
 class job(object):
 
     def __init__(self, queue, connection=None, timeout=None):
         """A decorator that adds a ``delay`` method to the decorated function,
-        which in turn creates a RQ job when called. Accepts a required ``queue``
-        argument that can be either a ``Queue`` instance or a string denoting
-        the queue name.  For example:
+        which in turn creates a RQ job when called. Accepts a required
+        ``queue`` argument that can be either a ``Queue`` instance or a string
+        denoting the queue name.  For example:
 
             @job(queue='default')
             def simple_add(x, y):
@@ -17,7 +18,7 @@ class job(object):
             simple_add.delay(1, 2) # Puts simple_add function into queue
         """
         self.queue = queue
-        self.connection = connection
+        self.connection = resolve_connection(connection)
         self.timeout = timeout
 
     def __call__(self, f):

rq/queue.py

@@ -1,5 +1,5 @@
 import times
-from .connections import get_current_connection
+from .connections import resolve_connection
 from .job import Job
 from .exceptions import NoSuchJobError, UnpickleError, InvalidJobOperationError
 from .compat import total_ordering
@@ -23,8 +23,7 @@ class Queue(object):
         """Returns an iterable of all Queues.
         """
         prefix = cls.redis_queue_namespace_prefix
-        if connection is None:
-            connection = get_current_connection()
+        connection = resolve_connection(connection)
 
         def to_queue(queue_key):
             return cls.from_queue_key(queue_key, connection=connection)
@@ -43,9 +42,7 @@ class Queue(object):
         return cls(name, connection=connection)
 
     def __init__(self, name='default', default_timeout=None, connection=None):
-        if connection is None:
-            connection = get_current_connection()
-        self.connection = connection
+        self.connection = resolve_connection(connection)
         prefix = self.redis_queue_namespace_prefix
         self.name = name
         self._key = '%s%s' % (prefix, name)
@@ -187,8 +184,7 @@ class Queue(object):
         Until Redis receives a specific method for this, we'll have to wrap it
         this way.
         """
-        if connection is None:
-            connection = get_current_connection()
+        connection = resolve_connection(connection)
         if blocking:
             queue_key, job_id = connection.blpop(queue_keys)
             return queue_key, job_id

tests/fixtures.py

@@ -3,7 +3,7 @@ This file contains all jobs that are used in tests.  Each of these test
 fixtures has a slighty different characteristics.
 """
 import time
-
+from rq import Connection
 from rq.decorators import job
 
 
@@ -51,6 +51,8 @@ class Calculator(object):
     def calculate(self, x, y):
         return x * y / self.denominator
 
-@job(queue='default')
-def decorated_job(x, y):
-    return x + y
+
+with Connection():
+    @job(queue='default')
+    def decorated_job(x, y):
+        return x + y