@ashcorr/loglevel-colored-level-prefix NPM

loglevel-colored-level-prefix

Forked from https://github.com/kentcdodds/loglevel-colored-level-prefix

loglevel plugin that adds colored level prefix (node only)

The problem

loglevel is great, and I find that I often want the log output to be formatted the same way every time. Also I don't really like some of the implementation of loglevel (specifically the fact that it uses some browser APIs for some things.

This solution

This exposes a function to get a logger (singleton) with colored prefixes for the level. Note that this only works in Node because it uses chalk.

Installation

This module is distributed via npm which is bundled with node and should be installed as one of your project's dependencies:

npm install --save loglevel-colored-level-prefix

Usage

const getLogger = require('loglevel-colored-level-prefix')
const options = {prefix: 'your-prefix', level: 'trace'}
const logger = getLogger(options)
logger.trace('WOW! What the stack trace!?')
// Trace: your-prefix [TRACE]: WOW! What the stack trace!?
//     at Logger.trace (<full-path>/node_modules/loglevel-colored-level-prefix/dist/index.js:54:24)
//     at ... etc
logger.debug('sup debug?')
// your-prefix [DEBUG]: sup debug?
logger.info('Hey info')
// your-prefix [INFO]: Hey info
logger.warn('Hi warn')
// your-prefix [WARN]: Hi warn
logger.error('Hello error')
// your-prefix [ERROR]: Hello error

Let's look at what that actually looks like...

options

prefix

?String - Whatever you want your prefix to be. Normally this is the tool that you're logging for. The getLogger function will return the same instance of the logger based on the given prefix.

level

?String - What you want the initial level to be set to. This defaults to: process.env.LOG_LEVEL || 'warn'. Possible options are (in order of verbosity): trace, debug, info, warn, error.

returns

An instance of a loglevel logger. Learn more about that API from the loglevel docs.

Inspiration

I wrote this because I wanted to use the plugin I created for prettier-eslint in prettier-eslint-cli. And I'll probably use it in other projects/tools as well.