fix: enable JSON logging via configuration and add regression test

[Jetemple]

Relevant issues

Fixes json_logs: true in config file not enabling JSON logging when using CONFIG_FILE_PATH #19036

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Type

🐛 Bug Fix

Changes

Bug: When using CONFIG_FILE_PATH environment variable (common in Helm/Kubernetes/Docker deployments), setting json_logs: true under litellm_settings in the config YAML file does not enable JSON logging.

Root cause: The CLI path (proxy_cli.py:672-682) correctly calls litellm._turn_on_json(), but the server startup path (proxy_server.py) only sets the attribute via setattr() without calling _turn_on_json() to reconfigure the logging handlers.

Fix: Added explicit handling for json_logs in ProxyConfig.load_config() that calls litellm._turn_on_json() when json_logs: true is set in the config.

Test: Added test_json_logs_calls_turn_on_json() regression test that verifies _turn_on_json() is called when loading a config with json_logs: true.

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Project	Deployment	Review	Updated (UTC)
litellm	Ready	Preview, Comment	Jan 13, 2026 4:43pm

[Sameerlite]

LGTM! Thanks!