acho

acho

An extremely simple (but powerful) logging system for NodeJS and browser.

Why

• Very easy to use, customize and extend.
• Expressive API with chaineable methods.
• Mininum dependencies, just focussing on one thing.

Install

npm install acho

If you want to use it in the browser (powered by Browserify):

bower install acho --save

and later add it to your HTML:

<script src="bower_components/acho/dist/acho.js"></script>

Usage

First steps

To use it, you just create a new logger instance.

var Acho = require('acho');
var acho = new Acho({color: true});

It's time to use it!

acho.info('hello world');
// => 'hello world'

All public methods are chaineables:

acho
.info('hello world')
.error('something bad happens');
// => 'info: hello world'
// => 'error: 'something bard happens'

Maybe you don't want to output the message, but store it for later use:

acho.push('success', 'good job!');
console.log(acho.messages.success);
// => ['good job']

If you want to print previously stored messages, just call the method print:

acho.print()
// => 'success: good job!'

You might be thinking: Can I combine both, to store and both print a message? Absolutely!

acho.add('info', 'this message is printed and stored');
// => 'info: 'this message is printed and stored'
console.log(acho.messages.info)
// => ['this message is printed and stored']

You can also modify the print method!

acho.print = function() {
  // You are in the acho scope, so you can use the properties
  // of the object. Check the API documentation.
  console.log();
  var _this = this;
  Object.keys(this.types).forEach(function(type) {
    _this.messages[type].forEach(function(message) {
      _this.printLine(type, message);
    });
  });
};

You can completely customize the library to your requirements: changes colors, add more types, sort the priorities... the internal structure of the object is public and you can edit it dynamically. You have the power.

Defining the level

Establishing the loglevel is a good way to filter out undesired information from output. The available levels are:

• error: Display calls to .error() messages.
• warning: Display calls from .error(), .warning() messages.
• success: Display calls from .error(), .warning(), success() messages.
• info: Display calls from .error(), .warning(), success(), info() messages.
• verbose: Display calls from .error(), .warning(), success(), info(), verbose() messages.
• debug: Display calls from .error(), .warning(), success(), info(), verbose(), debug() messages.
• silly: Display calls from .error(), .warning(), success(), info(), verbose(), debug(), silly() messages.
• silent: Avoid all output.

The default log level is info. You can define it in the the constructor:

var acho = new Acho({level: 'silly'})

or at runtime:

acho.level = 'debug';

Customization

By default the messages structure is brief: Just the message type followed by the message itself.

But you can easily modify the output. For example, let's add a timestamp to each message.

To customize the output we offer two methods, outputType and outputMessage:

acho = new Acho({
  color: true,
  level: 'silly',
  outputType: function(type) {
    return '[' + type + '] »';
  },

  outputMessage: function(message) {
    return Date() + ' :: ' + message;
  }
});

This results in your awesome output:

acho.info('I am hungry');
// => '[ info ] » Fri Mar 13 2015 18:12:48 GMT+0100 (CET) :: I am hungry'

You can modify the outputted message at any time.

API

.constructor({Object} [options])

Create a new logger. Available options:

• color {Boolean}: Enable or disable colorized output. false by default.
• level {String}: Provide the logging level. info by default.
• types {Object}: You can provide the types and priorities.
• outputType {Function}: Provide a function to customize the type in the output.
• outputMessage {Function}: Provide a function to customize the message in the output.
• print {Function}: Provide a function to print the messages.

.push({String} <type>, {String} <message>)

Store a message of given type internally.

.add({String} <type>, {String} <message>)

Store a message of given type internally and also output it.

.error({String} <message>)

Output a error message.

.warning({String} <message>)

Output a warning message.

.success({String} <message>)

Output a success message.

.info({String} <message>)

Output a info message.

.verbose({String} <message>)

Output a verbose message.

.debug({String} <message>)

Output a debug message.

.silly({String} <message>)

Output a silly message.

.isPrintable({String} <type>)

Determines if a type of message should be outputted.

.colorize({String} <color> {String} <message>)

Determines is a instance of acho is outputted with colors.

.printLine({String} <type> {String} <message>)

Combine .isPrintable and .colorize to print a line correctly.

.print()

Default loop to print the messages that are stored internally. By default it uses .printLine in each message iteration.

License

MIT © Kiko Beats

Changelog

1.0.2 (2015-03-17)

• 1.0.2 releases (fa3b7d1)
• Fix example.html, export proper module name to global space (f6ef959)
• refactor (1786df2)
• Removed makefile, added npm script for build (c441376)
• Update README.md (c61aeb7)
• updated (c217034)
• updated mocha reference to local dependency (7fc622c)
• Usability changes. Added a makefile for quick task execution. Added component.json so that we can (9e73dd4)

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