Hi everyone I am getting this error when calling create flow Prefect Community #ask-community

Hi everyone. I am getting this error when calling ...

Trevor Kramer

07/27/2021, 5:41 PM

Hi everyone. I am getting this error when calling create_flow_run from one flow to call another. This used to work. Is this still supported?

Unexpected error: TypeError('Object of type SUCCESS is not JSON serializable')

Traceback (most recent call last):

File "/root/.local/lib/python3.8/site-packages/prefect/engine/runner.py", line 48, in inner

new_state = method(self, state, *args, **kwargs)

File "/root/.local/lib/python3.8/site-packages/prefect/engine/task_runner.py", line 911, in get_task_run_state

result = self.result.write(value, **formatting_kwargs)

File "/root/.local/lib/python3.8/site-packages/prefect/engine/results/prefect_result.py", line 62, in write

new.location = self.serializer.serialize(new.value).decode("utf-8")

File "/root/.local/lib/python3.8/site-packages/prefect/engine/serializers.py", line 110, in serialize

return json.dumps(value).encode()

File "/usr/local/lib/python3.8/json/__init__.py", line 231, in dumps

return _default_encoder.encode(obj)

File "/usr/local/lib/python3.8/json/encoder.py", line 199, in encode

chunks = self.iterencode(o, _one_shot=True)

File "/usr/local/lib/python3.8/json/encoder.py", line 257, in iterencode

return _iterencode(o, 0)

File "/usr/local/lib/python3.8/json/encoder.py", line 179, in default

raise TypeError(f'Object of type {o.__class__.__name__} '

TypeError: Object of type SUCCESS is not JSON serializable

Kevin Kho

07/27/2021, 5:44 PM

Hey @Trevor Kramer, do you have an example of the code causing this? Yes

Client.create_flow_run

is still supported. what Prefect version are you on?

Trevor Kramer

07/27/2021, 5:45 PM

version 0.15.2

Trevor Kramer

07/27/2021, 5:46 PM

Copy code

flow_run_id = client.create_flow_run(
    flow_id,
    run_name=prefect.context.get("flow_run_name"),
    parameters={
        "input": yi,
        "stack": stack,
        "pruned_locations": pruned_locations,
        "image": image,
        "commit": commit,
    },
)

while True:
    time.sleep(10)
    flow_run_state = client.get_flow_run_info(flow_run_id).state
    if flow_run_state.is_finished():
        raise signal_from_state(flow_run_state)(
            f"{flow_run_id} finished in state {flow_run_state}"
        )

Trevor Kramer

07/27/2021, 5:49 PM

I am using prefect results - result=PrefectResult()

Kevin Kho

07/27/2021, 5:49 PM

Was the Flow kicked off and did it succeed? I’m wondering if this error is related to the Flow that ran.

Trevor Kramer

07/27/2021, 5:49 PM

it did succeed

Kevin Kho

07/27/2021, 5:59 PM

It seems the error is caused by the raise that is being serialized into the PrefectResult. Did that

raise

signal into the Prefect Result work before?

Kevin Kho

07/27/2021, 6:16 PM

The PrefectResult needs to be JSON Serializable and the raise is that is being returned so you need something other than the signal.

Trevor Kramer

07/27/2021, 9:14 PM

Thanks.

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