Logging

By default, all logs are printed to the console and saved to file in the logs/ folder. The log files will not exceed 5 MB.

In production mode, only logs with the level info or higher will be output to the console and saved to file. All logs are saved to the logs/combined.log file. Additionally, all error logs are saved to logs/error.log for easy inspection of program errors.

Customizing

You can customize the log formats in /helpers/logger.mjs. The config variable is worth mentioning here, as it contains the basic configuration for the file and console transports.

For example, you could output the file logs in prettyprinted JSON with timestamps:

 file: {
     level: environment === "production" ? "info" : "debug",
     filename: "logs/log.log",
     maxsize: 5000000, // 5MB
     maxFiles: 5,
     format: winston.format.combine(
         winston.format.errors({ stack: true }),
         winston.format.splat(),
         winston.format.uncolorize(),
-        winston.format.simple()
+        winston.format.timestamp(),
+        winston.format.prettyPrint(),
+        winston.format.json()
     )
 }

Find out more about customizing winston logs on the winston homepage (opens new window)