[serve] Add tracing support for Windows and enable test_tracing_utils

[TriNguyen1208]

Description

This PR enables test_tracing_utils for Windows by addressing file locking issues and cross-platform line ending discrepancies. It also ensures that tracing tests are no longer skipped on Windows.

Key Changes

• Re-enabled Windows Tests: Removed pytest.mark.skipif for the win32 platform to allow tracing tests to run in Windows environments.
• Fixed File Handle Leak in ConsoleSpanExporter: ConsoleSpanExporter was initialized with an inline open() call that was never explicitly closed, causing a PermissionError on Windows when attempting to delete span files after tests. Fixed by subclassing ConsoleSpanExporter with a shutdown() method that explicitly flushes and closes the file handle. provider.shutdown() is now called inside safe_remove() to trigger the cleanup chain before deletion.
• Improved Span Parsing: Replaced .split("}\n{") with re.split(r'}\s*\n\s*{', file_contents) in load_spans. This regex-based approach correctly handles different newline sequences (\n vs \r\n) and potential whitespace variations between JSON objects, preventing decoding failures.
• Explicit Exporter Path: Added tracing_exporter_import_path=DEFAULT_TRACING_EXPORTER_IMPORT_PATH across multiple test cases to ensure consistent tracing configuration.

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Related issues

Closes #61443

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Additional information

• Cleanup Refactor: Replaced all instances of shutil.rmtree and os.remove with safe_remove_directory for span directory management.
• Windows Compatibility Fix: The load_spans fix is critical for Windows where ConsoleSpanExporter may output CRLF (\r\n) line endings, which previously broke the manual JSON string splitting logic.

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Test Verification

• Platform: Windows 11 / Windows 10
• Command: pytest -v python/ray/serve/tests/test_tracing_utils.py
• Result: Verified that all tests in test_tracing_utils.py pass locally on Windows after applying these changes.

[gemini-code-assist]

Code Review

This pull request introduces a safe_remove_directory utility to handle Windows file locking issues during test cleanup and updates tracing tests to utilize a consistent exporter import path. Feedback was provided to improve the robustness of the safe_remove_directory function by addressing potential silent failures, ensuring idempotency, and reducing code duplication. Additionally, it is recommended to remove commented-out code in the load_spans function to improve readability.

[phmkhoi]

Hi @abrarsheikh @akyang-anyscale,

Could you please take a look at this PR when you have a chance? All available CI checks have passed, though Buildkite premerge is still waiting to be triggered.

Happy to make any changes based on your feedback. Thank you!

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{Reviewed by Cursor Bugbot for commit eaaf573. Configure here.}

[cursor]

Test relies on env var to reach error path

Medium Severity

Removing tracing_exporter_import_path=DEFAULT_TRACING_EXPORTER_IMPORT_PATH from the test_missing_dependencies call to setup_tracing causes the test to depend on the RAY_SERVE_TRACING_EXPORTER_IMPORT_PATH env var being set externally (by Bazel). Without it, the env var defaults to "", and setup_tracing returns False at the tracing_exporter_import_path == "" check before ever reaching the if not trace: check that raises ImportError. The pytest.raises(ImportError) block then fails because no exception is raised. Unlike other tests that inherently need tracing enabled, this test specifically needs a non-empty import path to exercise the dependency-check error path.

 

^{Reviewed by Cursor Bugbot for commit eaaf573. Configure here.}

[phmkhoi]

Hi @abrarsheikh,

Could you please take a look at this PR again when you have a chance? I have adjusted the code with your previous reviews, and all checks have passed.
Happy to make any changes based on your feedback. Thank you!

[abrarsheikh]

@TriNguyen1208 thanks for your contribution, I see you have access to a windows machine, if you wish to maintain serve for windows please reach out over slack, there are many other tests in the repo we are skipping for windows purely because the team doesn't have the bandwidth to maintain it. LMK.