psobot opened a new issue, #25401: URL: https://github.com/apache/beam/issues/25401
### What happened? When launching a Beam pipeline in Python, the `--save_main_session` flag can be used to serialize the local session's state and load it on the workers. However, if the deserialization of this main session fails, the pipeline continues to execute - just without its global state, causing `NameError`s in various places. These `NameError` exceptions don't hint at the original root cause (which is that the main session state failed to deserialize, for whatever reason) which causes a large amount of confusion, especially for those unfamiliar with the intricacies of how Beam works under the hood. I resolved [a similar issue back in Beam 2.31](https://github.com/apache/beam/pull/14706) (https://github.com/apache/beam/pull/14706) that failed to stop a job if the main session was corrupted; this seems similar. Expected behaviour: if a main session is present but fails to deserialize, this is considered a "hard error" that stops the entire Beam job from running and forces the programmer to deal with the cause of the failure, rather than proceeding to run the job's code in a half-working state. ### Issue Priority Priority: 2 (default / most bugs should be filed as P2) ### Issue Components - [X] Component: Python SDK - [ ] Component: Java SDK - [ ] Component: Go SDK - [ ] Component: Typescript SDK - [ ] Component: IO connector - [ ] Component: Beam examples - [ ] Component: Beam playground - [ ] Component: Beam katas - [ ] Component: Website - [ ] Component: Spark Runner - [ ] Component: Flink Runner - [ ] Component: Samza Runner - [ ] Component: Twister2 Runner - [ ] Component: Hazelcast Jet Runner - [X] Component: Google Cloud Dataflow Runner -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
