loglevel plugin that adds colored level prefix (node only)

Downloads in past


1.0.07 years ago7 years agoMinified + gzip package size for loglevel-colored-level-prefix in KB


loglevel plugin that adds colored level prefix (node only)
!Build Statusbuild-badgebuild !Code Coveragecoverage-badgecoverage !Dependenciesdependencyci-badgedependencyci !versionversion-badgepackage !downloadsdownloads-badgenpm-stat !MIT Licenselicense-badgeLICENSE
All Contributors !PRs Welcomeprs-badgeprs !Donatedonate-badgedonate !Code of Conductcoc-badgecoc !Roadmaproadmap-badgeroadmap !Examplesexamples-badgeexamples
!Watch on GitHubgithub-watch-badgegithub-watch !Star on GitHubgithub-star-badgegithub-star !Tweettwitter-badgetwitter

The problem

loglevelloglevel 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 chalkchalk.


This module is distributed via npmnpm which is bundled with nodenode and should be installed as one of your project's dependencies:
npm install --save loglevel-colored-level-prefix


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...



?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.


?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.


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


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

Other Solutions

I'm unaware of other plugins for loglevel that do what this one does. But there are many logging solutions out there...


Thanks goes to these people (emoji keyemojis):
Kent C. Dodds

💻 📖 🚇 ⚠️ | | :---: |
This project follows the all-contributorsall-contributors specification. Contributions of any kind welcome!