Documented the task message protocol.

docs/internals/protocol.rst

@@ -0,0 +1,49 @@
+=======================
+ Task Message Protocol
+=======================
+
+    * task
+        ``string``
+
+        Name of the task. **required**
+
+    * id
+        ``string``
+
+        Unique id of the task (UUID). **required**
+
+    * args
+        ``list``
+
+        List of arguments. Will be an empty list if not provided.
+
+    * kwargs
+        ``dictionary``
+
+        Dictionary of keyword arguments. Will be an empty dictionary if not
+        provided.
+
+    * retries
+        ``int``
+
+        Current number of times this task has been retried.
+        Defaults to ``0`` if not specified.
+
+    * eta
+        ``string`` (ISO 8601)
+
+        Estimated time of arrival. This is the date and time in ISO 8601
+        format. If not provided the message is not scheduled, but will be
+        executed asap.
+
+Example
+=======
+
+This is an example invocation of the ``celery.task.PingTask`` task in JSON
+format::
+
+    {"task": "celery.task.PingTask",
+     "args": [],
+     "kwargs": {},
+     "retries": 0,
+     "eta": "2009-11-17T12:30:56.527191"}