Introduction

bracketslogger is an enhanced console logger with the following features:

• the primary reason for its existence - accurate line numbering (note: provided source mapping is working correctly!)
• object output in firefox/chrome browser console
• node util.format() compatible sprintf() style replacements
  • the library detects the context (browser, Android, ...) and replaces %O and/or %j with JSON.stringify() as needed
  • the library detects the context (browser, Android, ...) and combines comma arguments, to workaround how Android console.log(A,B,C) will only output A
• colourisation in both Firefox/Chrome and the Android logcat output
  • uses CSS in browser
  • uses ansistyles in Android logcat

bracketslogger combines the best parts of both the debug and log-level packages. It is able to do this by sacrificing just a little bit of elegance - it produces accurate line numbers by returning a function that must be called to produce the actual console log output. Hence the name, bracketslogger

There is also a very small performance hit because a new anonymous function is created for each log output.

bracketslogger comes with a tslint rule that will warn if the brackets are missing. This wont help if you are using it from pure javascript however. See http://github.com/platfarm-com/bracketslogger-tslint-rules.git

This library is being used in a real (proprietary) Android app under development.

Usage

Typescript example:

import { Logging } from 'bracketslogger';
const Log = Logging.get('page.home');

// ...

Log.Debug('Hello, World')();
Log.Error('Something bad happened: %O', e)();

TODO

There is a whole bunch of stuff missing, Contributions gratefully accepted!

• Unit test suite
• Minifcation
• Linting
  • the library itself
  • an eslint rule to detect missing brackets when used from pure javascript
• Robustness
  • I've only used it from Ionic3 in browser and Android webview
• Examples
• Improve how options are exposed to the caller
  • at the moment there is a dogy heiristic that switches behaviour between Android logcat and browser
  • there are options to turn on/off colourisation and prefixes, these need to be exposed
• Test in pure javascript - I've only tested from typescript
• Test what happens in iOS
• Test in Internet Explorer or Safari (only tested in Firefox, Chrome and logcat)
• Test in Android in situations other than Ionic/Cordova webview (chromium) output
• Test in node.js CLI

Inspiration

I was frustrated at not having accurate line numbering of console output in the browser, but I liked how the use of css to colour the results made it easy to pick various component logs out.

bracketslogger uses the bind mechanism used by log-level and the colour and substitution flexibility of debug.

• debug - https://www.npmjs.com/package/debug
• log-level - https://github.com/pimterry/loglevel

License

Bracketslogger is licensed under the MPL (see https://www.mozilla.org/en-US/MPL/2.0/FAQ/

Briefly paraphrased, you can use Teuthis in a commercial setting, and the MPL does not have the "viral" component of the GPL. However modifications to files that are part of Teuthis that you wish to redistribute (by using in a web page or hybrid mobile app) must be made available, and also cannot be re-licensed.

The easiest way to make available is to submit a pull request :-)

Please contact Platfarm (http://www.platfarm.com) to negotiate a commercial license if compliance with the MPL 2.0 license is does not fit your use case.