just-enough-logger

Minimal logger for nodejs

Installation

npm install just-enough-logger

or

yarn add just-enough-logger

Usage

const { Logger } = require("just-enough-logger");
// or
// [DEPRECATED] const Logger = require("just-enough-logger").default;
// Default export is available for backward compatibility. It'll be removed in next version.

let log = new Logger();

// let log = new Logger(options?); // Check options

// By default, prints to a file and console
// Default file is current_directory/log.log
// Check the options for more details

log.info("this is info message");
// 10/2/2019, 12:57:14 AM : [INFO] : this is info message

log.warn("this is warn message");
// 10/2/2019, 12:57:14 AM : [WARN] : this is warn message

log.error("this is error message");
// 10/2/2019, 12:57:14 AM : [ERROR] : this is error message

Options

Pass the options object to Logger constructor.

transports

• Where to print log message
• Type: Array
• Valid Values: ["file", "console"]
• Default: ["file", "console"]

Example:

let log = new Logger({
  transports: ["console"], // Only prints on console
});

file

• Path of log file
• Type: Path String
• Valid Values: /path/to/log.log
• Default: [current_directory]/log.log

Example:

let log = new Logger({
  file: path.resolve(__dirname, "logs", "my-log.log"),
});

formatter

• Custom formatter
• Type: Function
• Signature: (message: string, level: "info" | "warn" | "error") => string
• Default: Returns log in format ${new Date().toLocaleString()} : [${level.toUpperCase()}] : ${message}

Example:

let log = new Logger({
  formatter: (message, level) => {
    return `${new Date()} ${level} ${message}`;
  },
});

Methods

Methods work on instance of Logger

getLogFilePath()

• Returns the path of log file.

let logger = new Logger();
console.log(logger.getLogFilePath()); // c:\Programming\my-project\log.log

getLogStream()

• Returns WriteStream of log file or null if file transports is not present.

let logger = new Logger();
console.log(logger.getLogStream());

License

MIT - @saisandeepvaddi