Merge pull request #2598 from ByteInternet/fix-exception-marshalling-with-json-serializer

Fix Exception marshalling with JSON serializer

celery/backends/amqp.py

@@ -195,7 +195,7 @@ class AMQPBackend(BaseBackend):
 
         def callback(meta, message):
             if meta['status'] in states.READY_STATES:
-                results[meta['task_id']] = meta
+                results[meta['task_id']] = self.meta_from_decoded(meta)
 
         consumer.callbacks[:] = [callback]
         time_start = now()

celery/tests/backends/test_amqp.py

@@ -13,6 +13,7 @@ from celery import states
 from celery.backends.amqp import AMQPBackend
 from celery.exceptions import TimeoutError
 from celery.five import Empty, Queue, range
+from celery.result import AsyncResult
 from celery.utils import uuid
 
 from celery.tests.case import (
@@ -246,10 +247,20 @@ class test_AMQPBackend(AppCase):
         with self.assertRaises(TimeoutError):
             b.wait_for(tid, timeout=0.01, cache=False)
 
-    def test_drain_events_remaining_timeouts(self):
+    def test_drain_events_decodes_exceptions_in_meta(self):
+        tid = uuid()
+        b = self.create_backend(serializer="json")
+        b.store_result(tid, RuntimeError("aap"), states.FAILURE)
+        result = AsyncResult(tid, backend=b)
 
-        class Connection(object):
+        with self.assertRaises(Exception) as cm:
+            result.get()
 
+        self.assertEqual(cm.exception.__class__.__name__, "RuntimeError")
+        self.assertEqual(str(cm.exception), "aap")
+
+    def test_drain_events_remaining_timeouts(self):
+        class Connection(object):
             def drain_events(self, timeout=None):
                 pass
 

tox.ini

@@ -48,7 +48,7 @@ deps = -r{toxinidir}/requirements/default.txt
        -r{toxinidir}/requirements/dev.txt
 setenv = C_DEBUG_TEST = 1
 commands = {toxinidir}/extra/release/removepyc.sh {toxinidir}
-           pip install -U -r{toxinidir}/requirements/dev.txt
+           pip install -q -U -r{toxinidir}/requirements/dev.txt
            nosetests -xsv --with-coverage --cover-inclusive --cover-erase []
 
 [testenv:pypy3]
@@ -59,7 +59,7 @@ deps = -r{toxinidir}/requirements/default.txt
        -r{toxinidir}/requirements/dev.txt
 setenv = C_DEBUG_TEST = 1
 commands = {toxinidir}/extra/release/removepyc.sh {toxinidir}
-           pip install -U -r{toxinidir}/requirements/dev.txt
+           pip install -q -U -r{toxinidir}/requirements/dev.txt
            nosetests -xsv --with-coverage --cover-inclusive --cover-erase []
 
 [testenv:docs]