refactor(logging): preserve explicit LiteLLM logger levels

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "infermesh"
-version = "0.3.1"
+version = "0.3.2"
 description = "Run large LLM batches from notebooks and scripts without rewriting concurrency or rate-limit glue."
 readme = "README.md"
 license = { text = "Apache-2.0" }

src/infermesh/_client_runtime.py

@@ -524,7 +524,16 @@ def _create_litellm_module(self) -> Any:
         import litellm
         import litellm._logging
 
-        litellm._logging.verbose_logger.setLevel(logging.WARNING)
+        self._set_default_litellm_logger_level(litellm._logging.verbose_logger)
         if hasattr(litellm._logging, "verbose_router_logger"):
-            litellm._logging.verbose_router_logger.setLevel(logging.WARNING)
+            self._set_default_litellm_logger_level(
+                litellm._logging.verbose_router_logger
+            )
         return litellm
+
+    @staticmethod
+    def _set_default_litellm_logger_level(litellm_logger: logging.Logger) -> None:
+        """Keep LiteLLM quiet unless the caller already configured its logger."""
+
+        if litellm_logger.level == logging.NOTSET:
+            litellm_logger.setLevel(logging.WARNING)

tests/test_client_runtime.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import base64
+import logging
 from pathlib import Path
 from typing import Any
 from unittest.mock import AsyncMock, patch
@@ -18,6 +19,51 @@
 )
 
 
+def _litellm_verbose_loggers() -> list[logging.Logger]:
+    """Return LiteLLM loggers that ``LMClient`` quiets by default."""
+
+    import litellm._logging
+
+    loggers = [litellm._logging.verbose_logger]
+    router_logger = getattr(litellm._logging, "verbose_router_logger", None)
+    if router_logger is not None:
+        loggers.append(router_logger)
+    return loggers
+
+
+def _restore_logger_levels(levels: dict[logging.Logger, int]) -> None:
+    for logger, level in levels.items():
+        logger.setLevel(level)
+
+
+def test_litellm_debug_loggers_are_preserved() -> None:
+    loggers = _litellm_verbose_loggers()
+    original_levels = {logger: logger.level for logger in loggers}
+    for logger in loggers:
+        logger.setLevel(logging.DEBUG)
+
+    client = LMClient(model="openai/test", api_base="http://localhost")
+    try:
+        assert all(logger.level == logging.DEBUG for logger in loggers)
+    finally:
+        client.close()
+        _restore_logger_levels(original_levels)
+
+
+def test_litellm_loggers_default_to_warning_when_unconfigured() -> None:
+    loggers = _litellm_verbose_loggers()
+    original_levels = {logger: logger.level for logger in loggers}
+    for logger in loggers:
+        logger.setLevel(logging.NOTSET)
+
+    client = LMClient(model="openai/test", api_base="http://localhost")
+    try:
+        assert all(logger.level == logging.WARNING for logger in loggers)
+    finally:
+        client.close()
+        _restore_logger_levels(original_levels)
+
+
 @pytest.mark.asyncio
 async def test_generate_responses_path(fake_client: LMClient) -> None:
     result = await fake_client.agenerate(