Flask context inside of delayed job.

AUTHORS

@@ -9,4 +9,6 @@ Development Lead
 Patches and Suggestions
 ```````````````````````
 
-- Jean-Philippe Serafin <https://github.com/jeanphix>
+- Jean-Philippe Serafin <https://github.com/jeanphix>
+- Mikhail Kashkin <https://github.com/xen>
+

CHANGES

@@ -3,6 +3,14 @@ Flask-RQ Changelog
 
 Here you can see the full list of changes between each Flask-RQ release.
 
+Version 0.3
+-----------
+
+Released August 14 2013
+
+- Added `ctx_delay` method. Allow to work inside of flask context in delayed job
+
+
 Version 0.2
 -----------
 

README.rst

@@ -69,6 +69,42 @@ A specific queue name can also be passed as argument:
 
     process.delay(2)
 
+Sometimes you need to access application configuration context in your job. 
+There is special way to be able to work inside of context. Please note this is 
+not the same context. This is new, specially created context with the same 
+configuration, but without blueprints or extensions that you probably expect.
+For example after long task you want to send email with result report:
+
+.. code-block:: python
+
+    @job()
+    def context_process():
+
+        #  Long stuff to process
+
+        from flask import current_app
+        from flask.ext.mail import Mail, Message
+        mail = Mail()
+        # current_app.config is almost the same as in Flask application
+        # that call your code 
+        mail.init_app(current_app)  
+        msg = Message("Report",
+                  sender="from@example.com",
+                  recipients=["to@example.com"])
+        mail.send(msg)
+
+
+    # inside of your view
+
+    @app.route('/make_long_report')
+    def report(project_id):
+        context_process.ctx_delay()
+        return 'Check your inbox in few minutes!'
+
+
+If you need to differentiate contexts then name of Flask application inside of 
+worker job is `worker`.
+
 
 ``get_queue`` function
 ~~~~~~~~~~~~~~~~~~~~~~

flask_rq.py

@@ -14,7 +14,7 @@
 
 import redis
 
-from flask import current_app
+from flask import current_app, Flask
 from redis._compat import urlparse
 from rq import Queue, Worker
 
@@ -73,6 +73,21 @@ def get_worker(*queues):
         connection=get_connection(queues[0]))
 
 
+class Cfg:
+    # Flask doesn't know how to read config from dictionary
+    # so we need to create "class-like" config
+    def __init__(self, **entries):
+        self.__dict__.update(entries)
+
+
+def ctx_run(fn, cfg, *args, **kwargs):
+    # call wrapper that create Flask context with stored config dict
+    app = Flask('worker')
+    app.config.from_object(cfg)
+    with app.app_context():
+        fn(*args, **kwargs)
+
+
 def job(func_or_queue=None):
     if callable(func_or_queue):
         func = func_or_queue
@@ -86,7 +101,13 @@ def delay(*args, **kwargs):
             q = get_queue(queue)
             return q.enqueue(fn, *args, **kwargs)
 
+        def ctx_delay(*args, **kwargs):
+            q = get_queue(queue)
+            cfg = Cfg(**dict(current_app.config))
+            return q.enqueue(ctx_run, fn, cfg, *args, **kwargs)
+
         fn.delay = delay
+        fn.ctx_delay = ctx_delay
         return fn
 
     if func is not None:

setup.py

@@ -19,7 +19,7 @@
 
 setup(
     name='Flask-RQ',
-    version='0.2',
+    version='0.3',
     url='http://packages.python.org/Flask-RQ/',
     license='MIT',
     author='Matthew Wright',

tests/flaskrq_tests.py

@@ -53,6 +53,11 @@ def test_job_default(self):
         self.assertEqual(len(get_queue().jobs), 1)
         get_worker().work(True)
 
+    def test_ctx_job(self):
+        simple.ctx_delay(0)
+        self.assertEqual(len(get_queue().jobs), 1)
+        get_worker().work(True)
+
     def test_job_specified_queue(self):
         specified.delay(3)
         self.assertEqual(len(get_queue('low').jobs), 1)

tests/jobs.py

@@ -13,3 +13,9 @@ def simple(i):
 def specified(i):
     time.sleep(5)
     return i
+
+@job
+def simple_ctx():
+    from flask import current_app
+    time.sleep(5)
+    return current_app.name