Improved logging setup with debug log files

backend/logging.py

@@ -1,27 +1,138 @@
 #-*- coding: utf-8 -*-
 
 import logging
+import logging.config
+from os.path import exists
+from typing import Any
 
+from backend.helpers import folder_path
+
+
+class InfoOnlyFilter(logging.Filter):
+	def filter(self, record: logging.LogRecord) -> bool:
+		return record.levelno == logging.INFO
+
+
+class DebuggingOnlyFilter(logging.Filter):
+	def filter(self, record: logging.LogRecord) -> bool:
+		return LOGGER.level == logging.DEBUG
+
+
+class ErrorColorFormatter(logging.Formatter):
+	def format(self, record: logging.LogRecord) -> Any:
+		result = super().format(record)
+		return f'\033[1;31:40m{result}\033[0m'
+
+
+LOGGER_NAME = "MIND"
+LOGGER_DEBUG_FILENAME = "MIND_debug.log"
+LOGGER = logging.getLogger(LOGGER_NAME)
+LOGGING_CONFIG = {
+	"version": 1,
+	"disable_existing_loggers": False,
+	"formatters": {
+		"simple": {
+			"format": "[%(asctime)s][%(levelname)s] %(message)s",
+			"datefmt": "%H:%M:%S"
+		},
+		"simple_red": {
+			"()": ErrorColorFormatter,
+			"format": "[%(asctime)s][%(levelname)s] %(message)s",
+			"datefmt": "%H:%M:%S"
+		},
+		"detailed": {
+			"format": "%(asctime)s | %(threadName)s | %(filename)sL%(lineno)s | %(levelname)s | %(message)s",
+			"datefmt": "%Y-%m-%dT%H:%M:%S%z",
+		}
+	},
+	"filters": {
+		"only_info": {
+			"()": InfoOnlyFilter
+		},
+		"only_if_debugging": {
+			"()": DebuggingOnlyFilter
+		}
+	},
+	"handlers": {
+		"console_error": {
+			"class": "logging.StreamHandler",
+			"level": "WARNING",
+			"formatter": "simple_red",
+			"stream": "ext://sys.stderr"
+		},
+		"console": {
+			"class": "logging.StreamHandler",
+			"level": "INFO",
+			"formatter": "simple",
+			"filters": ["only_info"],
+			"stream": "ext://sys.stdout"
+		},
+		"debug_file": {
+			"class": "logging.StreamHandler",
+			"level": "DEBUG",
+			"formatter": "detailed",
+			"filters": ["only_if_debugging"],
+			"stream": ""
+		}
+	},  
+	"loggers": {
+		LOGGER_NAME: {
+			"level": "INFO"
+		}
+	},
+	"root": {
+		"level": "DEBUG",
+		"handlers": [
+			"console",
+			"console_error",
+			"debug_file"
+		]
+	}
+}
 
 def setup_logging() -> None:
 	"Setup the basic config of the logging module"
-	logging.basicConfig(
-		level=logging.INFO,
-		format='[%(asctime)s][%(threadName)s][%(levelname)s] %(message)s',
-		datefmt='%Y-%m-%d %H:%M:%S',
-		force=True
-	)
+	logging.config.dictConfig(LOGGING_CONFIG)
 	return
 
-def set_log_level(level: int) -> None:
+def get_debug_log_filepath() -> str:
+	"""
+	Get the filepath to the debug logging file.
+	Not in a global variable to avoid unnecessary computation.
+	"""
+	return folder_path(LOGGER_DEBUG_FILENAME)
+
+def set_log_level(
+	level: int,
+	clear_file: bool = True
+) -> None:
 	"""Change the logging level
 
 	Args:
 		level (int): The level to set the logging to.
 			Should be a logging level, like `logging.INFO` or `logging.DEBUG`.
+
+		clear_file (bool, optional): Empty the debug logging file.
+			Defaults to True.
 	"""
-	logging.debug(f'Setting logging level: {level}')
-	logging.getLogger().setLevel(
-		level=level
-	)
+	LOGGER.debug(f'Setting logging level: {level}')
+	LOGGER.setLevel(level)
+
+	if level == logging.DEBUG:
+		stream_handler = logging.getLogger().handlers[
+			LOGGING_CONFIG["root"]["handlers"].index('debug_file')
+		]
+
+		file = get_debug_log_filepath()
+
+		if clear_file:
+			if exists(file):
+				open(file, "w").close()
+			else:
+				open(file, "x").close()
+
+		stream_handler.setStream(
+			open(file, "a")
+		)
+
 	return