FrankYang0529 opened a new pull request, #75538: URL: https://github.com/apache/airflow/pull/75538
### Why - #74690 let a Java task see when Airflow asks it to stop. #75421 reverted it because the K8s Lang-SDK test (`test_lang_sdk_mixed_language`) started to hang. A Java task sent its first request to the supervisor and then stopped logging. - #74690 added `@Synchronized` to `LogSender.configure` and `LogSender.send`. `LogSender` writes each log line with `runBlocking`. While `runBlocking` waits, it also runs other coroutines that are ready on the calling thread. - When the log connection opens, `configure` writes the messages that were logged before the connection opened. If the startup details arrive during that write, `configure` can run the task while it holds the `LogSender` lock. The task sends its first request. The thread that reads replies then blocks on the lock when it tries to log `Received` at debug level for the reply. As a result, the task waits for the reply forever. ### How - `LogSender` keeps its lock, but a separate thread writes each line while the caller waits with `Future.get()`. A thread that waits in `Future.get()` runs no coroutines, so a caller that holds the lock cannot run the task. - A caller that is already interrupted still gets its line written and keeps its interrupt status, as it did with `runBlocking`. On its own, `Future.get()` would throw `InterruptedException` at once for such a caller. --- ##### Was generative AI tooling used to co-author this PR? <!-- If generative AI tooling has been used in the process of authoring this PR, please change below checkbox to `[X]` followed by the name of the tool, uncomment the "Generated-by". --> - [X] Yes - Claude Code <!-- Generated-by: [Tool Name] following [the guidelines](https://github.com/apache/airflow/blob/main/contributing-docs/05_pull_requests.rst#gen-ai-assisted-contributions) --> -- 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]
