winston-wrap

This library is a simple wrapper around winston logger initialisation. Default config returns a logger with 2 transports (file and console) pre-configured.

Setup

npm install winston-wrap

Usage

winston-wrap exposes a single function; simply pass to this function a label name, and, why not, some options (as shown bellow) and it will return a winston logger object ready to be used.

Default Usage

With no parameters passed to the require, 2 transports are created with the following pre-configured caracteristics :

console :

config.file = {
	level: 'debug',
	filename: `./output-${appName}.log`,
	handleExceptions: true,
	maxsize: 5242880, // 5MB
	maxFiles: 5,
	format: format,
};

file :

config.console = {
	handleExceptions: true,
	format: combine(
		logformat.colorize(),
		format,
	),
};

colors :

config.colors = {
	error: 'red',
	warn: 'magenta',
	info: 'green',
	verbose: 'yellow',
	debug: 'cyan',
	silly: 'white',
};

finally, the logger :

config.logger = {
	level: 'debug',
	exitOnError: false, // do not exit on handled exceptions
	transports: [
		new transports.File(config.file),
		new transports.Console(config.console),
	],
};

In short, logs are sent to a file (filename: ./output-${appName}.log,) and simultaneously to the console (with some colorization for the latter).

Example with all defaults :

const logger = require('winston-wrap');
const options = { file: null, console: { level: 'verbose' } }

logger.debug('options %o', options);

will output the following text in console and in ./output.log :

2019-01-02 14:40:30 [debug]: options { file: null, console: { level: 'verbose' } }

Usage with a label

If you pass a string to the require creating the logger, you will add a label to each log line. This label can be used to identify the module which generated the line :

Logs are still sent to a file (filename: ./output-${appName}.log,) and to the console.

Example :

const logger = require('winston-wrap')('index.js');
const options = { file: null, console: { level: 'verbose' } }

logger.debug('options %o', options);

will output the following text in console and in ./output.log :

2019-01-02 14:40:30 [debug]: index.js - options { file: null, console: { level: 'verbose' } }

Usage with winston options

You can also pass an option object when calling the require. This object accepts the following attributes :

options = {
	file: {},
	console: {},
	colors: {},
	logger:{},
}

These attributes will simply be merged with the default config (described above) to allow you to overide it if needed. If you want to deactivate a transport, just affect a null attribute.

The configuration of each sub-object has to follow winston rules as shown in their documentation. file is a transport.File configuration object, console a transport.Console one, etc...

Example 1 :

const options = { file: null, console: { level: 'verbose' } }
const logger = require('winston-wrap')('index.js', options);

logger.debug('options %o', options);

will output nothing, ...anywhere. (file output is disabled and console output is elevated to verbose)

Example 2 :

const options = { file: null, console: { level: 'verbose' } }
const logger = require('winston-wrap')('index.js', options);

logger.warn('options %o', options);

will output the following to the console (and no file) :

2019-01-02 14:40:30 [warn]: index.js - options { file: null, console: { level: 'verbose' } }

Example 3 :

const app = 'myApp';
const options = { file: { filename: `/home/pi/output-${app}.log` } }
const logger = require('winston-wrap')('index.js', options);

logger.info('options %o', options);

will output anything to the console and the following to an app dedicated output log in your /home/pi directory :

2019-01-02 14:40:30 [info]: index.js - options { file: { filename: '/home/pi/output-myApp.log' } }