Remote function returning non-serializable type no longer shuts worker down (#384)

* Moved put_objects in main_loop to inside of try block

* Added test for failed serialization

* Fixed naming

* Minor

lib/python/ray/worker.py

@@ -964,6 +964,7 @@ def main_loop(worker=global_worker):
       outputs = worker.functions[function_name].executor(arguments) # execute the function
       if len(return_objectids) == 1:
         outputs = (outputs,)
+      store_outputs_in_objstore(return_objectids, outputs, worker) # store output in local object store
     except Exception as e:
       # If the task threw an exception, then record the traceback. We determine
       # whether the exception was thrown in the task execution by whether the
@@ -975,8 +976,6 @@ def main_loop(worker=global_worker):
       # Notify the scheduler that the task failed.
       raylib.notify_failure(worker.handle, function_name, str(failure_object), raylib.FailedTask)
       _logger().info("While running function {}, worker threw exception with message: \n\n{}\n".format(function_name, str(failure_object)))
-    else:
-      store_outputs_in_objstore(return_objectids, outputs, worker) # store output in local object store
     # Notify the scheduler that the task is done. This happens regardless of
     # whether the task succeeded or failed.
     raylib.ready_for_new_task(worker.handle)

test/failure_test.py

@@ -34,6 +34,18 @@ class FailureTest(unittest.TestCase):
 
     ray.worker.cleanup()
 
+  def testUnknownSerialization(self):
+    reload(test_functions)
+    ray.init(start_ray_local=True, num_workers=1, driver_mode=ray.SILENT_MODE)
+
+    test_functions.test_unknown_type.remote()
+    time.sleep(0.2)
+    task_info = ray.task_info()
+    self.assertEqual(len(task_info["failed_tasks"]), 1)
+    self.assertEqual(len(task_info["running_tasks"]), 0)
+
+    ray.worker.cleanup()
+
 class TaskStatusTest(unittest.TestCase):
   def testFailedTask(self):
     reload(test_functions)

test/test_functions.py

@@ -116,3 +116,11 @@ def test_return1():
 @ray.remote([], [int, float])
 def test_return2():
   return 2.0, 3.0
+
+class TestClass(object):
+  def __init__(self):
+    self.a = 5
+
+@ray.remote([], [TestClass])
+def test_unknown_type():
+  return TestClass()