feat(logging): Add environment-based logger configuration and cleanup logging init

kubectl_mcp_tool/mcp_server.py

@@ -11,6 +11,9 @@
 from typing import Dict, Any, List, Optional, Callable, Awaitable
 
 import warnings
+
+from kubectl_mcp_tool.utils.logging_util import set_logger_with_envs
+
 warnings.filterwarnings(
     "ignore",
     category=RuntimeWarning,
@@ -36,8 +39,8 @@
 from .natural_language import process_query
 
 # Configure logging
-logging.basicConfig(level=logging.DEBUG, format="%(asctime)s - %(name)s - %(levelname)s - %(message)s")
 logger = logging.getLogger("mcp-server")
+set_logger_with_envs(logger)
 
 class MCPServer:
     """MCP server implementation."""
@@ -899,4 +902,4 @@ async def serve_sse(self, port: int):
     except Exception as e:
         logger.error(f"Server exited with error: {e}", exc_info=True)
     finally:
-        logger.info("Shutting down server.")
+        logger.info("Shutting down server.")

kubectl_mcp_tool/utils/logging_util.py

@@ -0,0 +1,42 @@
+import logging
+import os
+import sys
+
+
+def set_logger_with_envs(logger: logging.Logger):
+    """
+    Set the logger with logging related environment variables
+
+    TODO: This is temporary logger setting function. logger setting needs to be organized in the future.
+
+    Args:
+        logger: logger to set with environment variables
+    """
+
+    logger.propagate = False
+
+    # log level setting
+    if os.environ.get("MCP_DEBUG", "").lower() in ("1", "true"):
+        # MCP_DEBUG has higher priority than KUBECTL_MCP_LOG_LEVEL
+        log_level = logging.DEBUG
+    elif log_level_str := os.environ.get("KUBECTL_MCP_LOG_LEVEL"):
+        # log_level_str is "DEBUG", "INFO", "WARNING", or "ERROR"
+        log_level = getattr(logging, log_level_str.upper())
+    else:
+        log_level = logging.INFO
+
+    logger.setLevel(level=log_level)
+
+    # NOTE: some script (e.g. mcp_server.py) loads logger twice when it runs. To prevent duplicate logging.
+    if not logger.handlers:
+        # logger handler setting
+        log_file = os.environ.get("MCP_LOG_FILE")
+        if log_file:
+            os.makedirs(os.path.dirname(log_file), exist_ok=True)
+            handler = logging.FileHandler(log_file)
+        else:
+            handler = logging.StreamHandler(sys.stderr)
+
+        formatter = logging.Formatter("%(asctime)s - %(levelname)s - %(name)s - %(message)s")
+        handler.setFormatter(formatter)
+        logger.addHandler(handler)