sorry for all the questions lately, but here's ano...
# prefect-community
sorry for all the questions lately, but here's another one: When running a shell task in my flows I keep getting this error -
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May 26th 2020 at 12:39:41pm | prefect.CloudTaskRunner
ERROR lens
Failed to set task state with error: ClientError([{'message': "{'cached_inputs': defaultdict(<class 'dict'>, {'command': {'value': {'type': ['Unsupported value: ConstantResult']}}})}", 'locations': [{'line': 6, 'column': 13}], 'path': ['set_task_run_states', 'states', 0, 'id'], 'extensions': {'code': 'INTERNAL_SERVER_ERROR'}}])
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/prefect/engine/cloud/", line 123, in call_runner_target_handlers
  File "/usr/local/lib/python3.7/site-packages/prefect/client/", line 1104, in set_task_run_state
  File "/usr/local/lib/python3.7/site-packages/prefect/client/", line 226, in graphql
    raise ClientError(result["errors"])
prefect.utilities.exceptions.ClientError: [{'message': "{'cached_inputs': defaultdict(<class 'dict'>, {'command': {'value': {'type': ['Unsupported value: ConstantResult']}}})}", 'locations': [{'line': 6, 'column': 13}], 'path': ['set_task_run_states', 'states', 0, 'id'], 'extensions': {'code': 'INTERNAL_SERVER_ERROR'}}]
and then my flow just hangs in a pending state afterwards, any idea what this could be?
Absolutely no reason to apologize for all the questions-- this is good stuff! Taking a look at your stack trace now.
Is your shell task the only task that fails in this manner? Trying to narrow down the culprit.
yes any Shell task fails, i have a previous non-shell task before this works fine
Are you using Cloud or Server as your orchestration layer?
Gotcha. Do you know offhand what version of Server you're running? I'm wondering if this is due to running an older version of Server with a flow registered with a more recent version of Prefect Core.
ah this is definetly the case, i'm using server version 10.4, but the flow was made with 11.1
updating now and trying
ok i think that did it. There should be a better way to tell between flow and server version mis-matches. The server already knows what version each flow was registered under
There’s definitely room for us to improve there— thank you for putting it on our radar.