angular-simple-logger

A simple logger for AngularJS 1.x with configurable log levels and optional debug integration.

Why does this still exist?

Good question. AngularJS hit end-of-life in 2022 and yet this package still pulls ~7,000 downloads per week (365k+ per year). That's because the real world doesn't care about deprecation notices — enterprise apps built on AngularJS are still running in production, and they still need their dependencies maintained.

This library is a dependency of angular-google-maps and other AngularJS packages that are, for better or worse, still in active use. As long as people are downloading it, we'll keep the lights on: modern builds, working CI, and security patches.

What about Angular 2+?

No plans — and here's why it doesn't make sense:

This library exists because AngularJS 1.x had its own dependency injection system and module lifecycle. You couldn't just import a logger — you needed it wrapped as an AngularJS service/provider to play nice with $log, $provide.decorator, and the digest cycle. That's what nemLogging does.

Angular 2+ doesn't have this problem. Modern Angular uses standard ES modules and TypeScript imports. There's no special DI wrapper needed to use a logging library — you just import it directly. The entire reason this package exists is an AngularJS-specific constraint that no longer applies.

If you're on Angular 2+ (or any modern framework), use these instead:

• debug-fabulous (GitHub) — lazy-eval wrapper around debug that won't eat your CPU when disabled. Drop-in replacement with zero framework coupling.
• debug (GitHub) — the OG. Tiny, namespaced, colored output. Works everywhere.

// That's it. No module wrapper needed.
import debug from 'debug-fabulous';
const log = debug('myApp:component');
log('just works');

If you've migrated to modern Angular, you've already outgrown this package. Congratulations. 🎓

Installation

npm install angular-simple-logger

Light version (no debug dependency)

If you don't need the debug module integration:

import 'angular-simple-logger/light';
// or
require('angular-simple-logger/light');

Usage

As a module dependency

import angular from 'angular';
import 'angular-simple-logger';

angular.module('myApp', ['nemLogging']);

Basic logging

angular.module('myApp').controller('MyCtrl', ['nemSimpleLogger', function(nemSimpleLogger) {
  // Default level is 'error' — only error and log will output
  nemSimpleLogger.error('This will show');
  nemSimpleLogger.debug('This will NOT show');

  // Enable all levels
  nemSimpleLogger.currentLevel = nemSimpleLogger.LEVELS.debug;
  nemSimpleLogger.debug('Now this shows!');
}]);

Log levels

Levels are ordered: debug (0) < info (1) < warn (2) < error (3) < log (4).

Setting currentLevel to a value means that level and all higher levels will output.

nemSimpleLogger.currentLevel = nemSimpleLogger.LEVELS.warn;
// warn, error, and log will output. debug and info will not.

Disable all logging

nemSimpleLogger.doLog = false;

Spawn independent loggers

// From an existing logger object
const childLogger = nemSimpleLogger.spawn();
childLogger.currentLevel = childLogger.LEVELS.debug; // independent level

// With debug namespace (full version only)
const dbgLogger = nemSimpleLogger.spawn('myApp:worker');
dbgLogger.debug('colored debug output via visionmedia/debug');

Decorate $log

angular.module('myApp').config(function($provide, nemSimpleLoggerProvider) {
  $provide.decorator(...nemSimpleLoggerProvider.decorator);
});

// Now $log has level filtering:
angular.module('myApp').run(function($log) {
  $log.debug('works with levels!');
});

Enable debug namespaces

angular.module('myApp').config(function(nemDebugProvider) {
  nemDebugProvider.debug.enable('myApp:*');
});

API

nemSimpleLogger

| Property/Method | Description | |---|---| | debug(...) | Log at debug level | | info(...) | Log at info level | | warn(...) | Log at warn level | | error(...) | Log at error level | | log(...) | Log at log level | | currentLevel | Current minimum log level (default: LEVELS.error) | | doLog | Boolean to enable/disable all logging (default: true) | | LEVELS | Object with level constants: { debug: 0, info: 1, warn: 2, error: 3, log: 4 } | | spawn([logger\|namespace]) | Create a child logger. Pass a string for debug namespace (full version). |

nemDebug (full version only)

The debug module, available as both a service and provider.

Migrating from 0.1.x

• Source converted from CoffeeScript to ES6
• Build system changed from Gulp to Rollup
• Now provides UMD + ESM bundles
• debug upgraded to v4
• Public API is unchanged

Sponsor

If you find this useful, consider sponsoring @nmccready.

License

MIT