[LingYi-Liang]

Overview

Add request_body_log_level to --logging-config and use the resolved value in both API and render servers, following the post-merge request on #60630.

Claims

• JSON, dotted CLI and YAML settings override VLLM_REQUEST_BODY_LOG_LEVEL.
• Existing environment defaults, level aliases, invalid-level warning behavior and body truncation remain supported.

Validation

uv run --offline --no-project --python .venv/bin/python -m pytest \
  tests/entrypoints/serve/utils/test_request_logger.py \
  tests/entrypoints/common/test_cli_args.py tests/test_logger.py \
  tests/entrypoints/launchers/render/test_app_state.py -q

After syncing with main b439421, the same 113 tests passed on bdb65b8 in six serial batches to fit the local memory budget (0 failures, errors or skips). Applicable pre-commit hooks also passed, including mypy and test CI wiring.

The earlier HTTP/GPU checks below ran on 0eee4d1, before that main sync; they were not rerun for bdb65b8.

Normal render-server HTTP checks confirmed INFO/DEBUG overrides in both directions and environment-only compatibility. All three changed-source response JSONs matched the baseline.

A normal API-server GPU smoke check with a local two-layer synthetic Llama and dummy weights returned four identical token IDs, text and usage before/after; the CLI-selected INFO body record was emitted with an environment default of DEBUG. This checks configuration and serving, not model quality or performance. Both sources logged EngineDeadError during requested shutdown after successful generation; owned processes exited and no serving-time error was observed.

Details

The string field retains Python logging aliases and warn-and-skip behavior for invalid legacy values, including when --log-level or --log-config-file reconstructs the configuration. Logger/handler thresholds still apply.

This does not duplicate #62108, which guards serialization when logging is disabled, or #58712, which adds color/stream configuration. Their changes are outside this patch. AI assistance was used for investigation, implementation and validation.

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Pull Request Checklist

• I used vLLM's /pr-checklist skill. (Mandatory for agents, optional for humans).

• AI assistance was used during the creation of this PR.

• Design Fit: Minimizes impact on core components, reuses existing functionality, and justifies added complexity.

• Testing and Validation: Validates the change and ensures any added tests are meaningful and reliable, with CI coverage or documented CI resource constraints and validation performed outside CI.

• Code Quality and Style: Keeps code and comments clear and concise, and updates relevant documentation and examples.

• Pull Request Contents: Includes a brief summary and relevant links, supports claims with evidence, explains root causes and implementation trade-offs, and follows the contributing guide.

[claude]

Claude Code Review

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[mergify]

Documentation preview: https://vllm--62328.org.readthedocs.build/en/62328/

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @LingYi-Liang.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[LingYi-Liang]

Hi @markmc, thank you for the guidance in your comment on #60630. I've followed your suggestion to configure request body log levels through LoggingConfig in both API and render servers, preserving the environment defaults and level aliases. The 113 tests and scoped pre-commit checks passed on bdb65b8. When you have time, I'd appreciate your feedback on whether this matches what you had in mind.