feat: use flush in atexit to not block results

lib/crewai/src/crewai/crew.py

@@ -732,7 +732,6 @@ class Crew(FlowTrackable, BaseModel):
             )
             raise
         finally:
-            crewai_event_bus.flush()
             detach(token)
 
     def kickoff_for_each(
@@ -881,7 +880,6 @@ class Crew(FlowTrackable, BaseModel):
             )
             raise
         finally:
-            await asyncio.to_thread(crewai_event_bus.flush)
             detach(token)
 
     async def akickoff_for_each(

lib/crewai/src/crewai/events/event_bus.py

@@ -556,6 +556,9 @@ class CrewAIEventsBus:
             wait: If True, wait for all pending tasks to complete before stopping.
                   If False, cancel all pending tasks immediately.
         """
+        if wait:
+            self.flush()
+
         with self._rwlock.w_locked():
             self._shutting_down = True
             loop = getattr(self, "_loop", None)

lib/crewai/src/crewai/flow/flow.py

@@ -1448,7 +1448,6 @@ class Flow(Generic[T], metaclass=FlowMeta):
 
             return final_output
         finally:
-            await asyncio.to_thread(crewai_event_bus.flush)
             detach(flow_token)
 
     async def akickoff(

lib/crewai/tests/cassettes/events/TestAgentEventOrdering.test_agent_events_have_event_ids.yaml

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lib/crewai/tests/cassettes/events/TestAgentEventOrdering.test_llm_events_have_parent.yaml

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lib/crewai/tests/cassettes/events/TestCrewEventOrdering.test_crew_completed_after_started.yaml

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lib/crewai/tests/cassettes/events/TestCrewEventOrdering.test_crew_events_have_event_ids.yaml

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lib/crewai/tests/cassettes/events/TestCrewEventOrdering.test_task_parent_is_crew.yaml

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lib/crewai/tests/events/test_event_ordering.py

@@ -129,6 +129,7 @@ class TestCrewEventOrdering:
         )
         crew = Crew(agents=[agent], tasks=[task], verbose=False)
         crew.kickoff()
+        crewai_event_bus.flush()
 
         started = collector.first(CrewKickoffStartedEvent)
         completed = collector.first(CrewKickoffCompletedEvent)
@@ -157,6 +158,7 @@ class TestCrewEventOrdering:
         )
         crew = Crew(agents=[agent], tasks=[task], verbose=False)
         crew.kickoff()
+        crewai_event_bus.flush()
 
         started = collector.first(CrewKickoffStartedEvent)
         completed = collector.first(CrewKickoffCompletedEvent)
@@ -183,6 +185,7 @@ class TestCrewEventOrdering:
         )
         crew = Crew(agents=[agent], tasks=[task], verbose=False)
         crew.kickoff()
+        crewai_event_bus.flush()
 
         crew_started = collector.first(CrewKickoffStartedEvent)
         task_started = collector.first(TaskStartedEvent)
@@ -272,6 +275,7 @@ class TestFlowWithCrewEventOrdering:
 
         flow = SimpleFlow()
         flow.kickoff()
+        crewai_event_bus.flush()
 
         flow_started = collector.first(FlowStartedEvent)
         flow_finished = collector.first(FlowFinishedEvent)
@@ -305,6 +309,7 @@ class TestFlowWithCrewEventOrdering:
 
         flow = FlowWithMethod()
         flow.kickoff()
+        crewai_event_bus.flush()
 
         flow_started = collector.first(FlowStartedEvent)
         method_started = collector.first(MethodExecutionStartedEvent)
@@ -336,6 +341,7 @@ class TestFlowWithCrewEventOrdering:
 
         flow = FlowWithCrew()
         flow.kickoff()
+        crewai_event_bus.flush()
 
         method_started = collector.first(MethodExecutionStartedEvent)
         crew_started = collector.first(CrewKickoffStartedEvent)
@@ -387,6 +393,7 @@ class TestFlowWithMultipleCrewsEventOrdering:
 
         flow = TwoCrewFlow()
         flow.kickoff()
+        crewai_event_bus.flush()
 
         crew_started_events = collector.all_of(CrewKickoffStartedEvent)
 
@@ -432,6 +439,7 @@ class TestFlowWithMultipleCrewsEventOrdering:
 
         flow = SequentialCrewFlow()
         flow.kickoff()
+        crewai_event_bus.flush()
 
         crew_started_events = collector.all_of(CrewKickoffStartedEvent)
 
@@ -482,6 +490,7 @@ class TestFlowWithMultipleCrewsEventOrdering:
 
         flow = ParentTestFlow()
         flow.kickoff()
+        crewai_event_bus.flush()
 
         crew_started_events = collector.all_of(CrewKickoffStartedEvent)
         task_started_events = collector.all_of(TaskStartedEvent)
@@ -496,4 +505,4 @@ class TestFlowWithMultipleCrewsEventOrdering:
         task2_parent = task_started_events[1].parent_event_id
 
         assert task1_parent == crew1_id
-        assert task2_parent == crew2_id
+        assert task2_parent == crew2_id