[fix][5889686] AutoCast: Fix logger

Previously relied on quantization logger, which caused logs to be suppressed when
onnx.autocast was used directly
Instead:
- Inherit format and level if called from onnx.quantization
- Configure independent format and level if called from onnx.autocast

Signed-off-by: Gal Hubara Agam <96368689+galagam@users.noreply.github.com>

Author: galagam

modelopt/onnx/autocast/logging_config.py

@@ -22,26 +22,41 @@
 
 import logging
 import os
+import sys
 
-# Create a parent logger for all AutoCast components
-logger = logging.getLogger("autocast")
+# Create a logger for all AutoCast components as a child of modelopt.onnx
+# This ensures autocast inherits log level and format when called from quantization
+logger = logging.getLogger("modelopt.onnx.autocast")
 
 
 def configure_logging(level=logging.INFO, log_file=None):
     """Configure logging for all AutoCast components.
 
     Args:
-        level: The logging level to use (default: logging.INFO).
+        level: The logging level to use. Can be a string (e.g., "DEBUG", "INFO") or
+               a logging constant (e.g., logging.DEBUG). Default: logging.INFO.
         log_file: Optional path to a log file. If provided, logs will be written to this file
                  in addition to stdout (default: None).
     """
-    # Set level for the parent logger and all child loggers
+    # Check if parent logger (modelopt.onnx) already has handlers configured
+    parent_logger = logging.getLogger("modelopt.onnx")
+    parent_has_handlers = len(parent_logger.handlers) > 0
+
+    # If parent is configured and no explicit level provided, inherit parent's level
+    if parent_has_handlers and level == logging.INFO:
+        level = parent_logger.level
+
+    # Set level for the autocast logger (accepts both string and int)
     logger.setLevel(level)
 
     # Remove any existing handlers to ensure clean configuration
     for handler in logger.handlers[:]:
         logger.removeHandler(handler)
 
+    formatter = logging.Formatter(
+        "%(asctime)s - %(name)s - %(levelname)s - %(filename)s - %(message)s"
+    )
+
     # Add file handler if log_file is specified
     if log_file:
         try:
@@ -50,24 +65,28 @@ def configure_logging(level=logging.INFO, log_file=None):
             if log_dir:
                 os.makedirs(log_dir, exist_ok=True)
 
-            formatter = logging.Formatter(
-                "%(asctime)s - %(name)s - %(levelname)s - %(filename)s - %(message)s"
-            )
             file_handler = logging.FileHandler(log_file)
             file_handler.setFormatter(formatter)
             logger.addHandler(file_handler)
             logger.info(f"Logging configured to write to file: {log_file}")
         except Exception as e:
             logging.error(f"Failed to setup file logging to {log_file}: {e!s}")
 
-    # Allow log messages to propagate to the root logger for testing compatibility
-    # This enables pytest's caplog fixture to capture logs while still maintaining
-    # our custom formatting through the handlers above
-    logger.propagate = True
+    if parent_has_handlers:
+        # Parent logger is configured (called from quantization/other onnx modules)
+        # Propagate to parent to use its handlers and format
+        logger.propagate = True
+    else:
+        # Standalone mode (called directly via python3 -m modelopt.onnx.autocast)
+        # Add our own console handler with autocast-specific format
+        console_handler = logging.StreamHandler(sys.stdout)
+        console_handler.setFormatter(formatter)
+        logger.addHandler(console_handler)
+        logger.propagate = False
 
     # Ensure all child loggers inherit the level setting
     for name in logging.root.manager.loggerDict:
-        if name.startswith("autocast"):
+        if name.startswith("modelopt.onnx.autocast"):
             logging.getLogger(name).setLevel(level)