Add option to log non-error output to stdout

- No change to default behaviour
- Adds CLI argument: --log-stdout
- With this arg present, any logging of a level below logging.ERROR will be sent to stdout instead of stderr

app/logger.py

@@ -51,7 +51,7 @@ def on_flush(callback):
     if stderr_interceptor is not None:
         stderr_interceptor.on_flush(callback)
 
-def setup_logger(log_level: str = 'INFO', capacity: int = 300):
+def setup_logger(log_level: str = 'INFO', capacity: int = 300, use_stdout: bool = False):
     global logs
     if logs:
         return
@@ -70,4 +70,15 @@ def setup_logger(log_level: str = 'INFO', capacity: int = 300):
 
     stream_handler = logging.StreamHandler()
     stream_handler.setFormatter(logging.Formatter("%(message)s"))
+
+    if use_stdout:
+        # Only errors and critical to stderr
+        stream_handler.addFilter(lambda record: not record.levelno < logging.ERROR)
+
+        # Lesser to stdout
+        stdout_handler = logging.StreamHandler(sys.stdout)
+        stdout_handler.setFormatter(logging.Formatter("%(message)s"))
+        stdout_handler.addFilter(lambda record: record.levelno < logging.ERROR)
+        logger.addHandler(stdout_handler)
+
     logger.addHandler(stream_handler)

comfy/cli_args.py

@@ -141,6 +141,7 @@ parser.add_argument("--disable-all-custom-nodes", action="store_true", help="Dis
 parser.add_argument("--multi-user", action="store_true", help="Enables per-user storage.")
 
 parser.add_argument("--verbose", default='INFO', const='DEBUG', nargs="?", choices=['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], help='Set the logging level')
+parser.add_argument("--log-stdout", action="store_true", help="Send normal process output to stdout instead of stderr (default).")
 
 # The default built-in provider hosted under web/
 DEFAULT_VERSION_STRING = "comfyanonymous/ComfyUI@latest"

main.py

@@ -17,7 +17,7 @@ if __name__ == "__main__":
     os.environ['DO_NOT_TRACK'] = '1'
 
 
-setup_logger(log_level=args.verbose)
+setup_logger(log_level=args.verbose, use_stdout=args.log_stdout)
 
 def apply_custom_paths():
     # extra model paths