promiser

Promiser

promiser is a simple manager of deferreds by name. Rather than creating and maintaining references to jQuery.Deferred objects, simply register a handler by name and resolve or reject it by name.

promiser.done('test', function() {
    console.log('hello world');
});

promiser.resolve('test');

promiser.isResolved('test'); // true

The promiser API includes all the methods on the jQuery Deferred object.

Chaining works as expected:

promiser
    .done('test1', function() { ... })
    .done('test2', function() { ... })
    .done('test3', function() { ... });

For a more elegant approach, an object can be passed:

promiser.done({
    test1: function() { ... },
    test2: function() { ... },
    test3: function() { ... }
});

It supports the when method:

promiser.when('test1', 'test2', 'test3', function() {
    console.log('all done!');
});

Promiser can manage other deferred for you:

promiser.manage('ajax', $.ajax({ ... }));

It can also stop managing a deferred:

var xhr = promiser.unmanage('ajax');

You can even reset a deferred. This provides a clean alternative to passing around references to deferred objects:

promiser.reset('test1');

Deferreds can be watched for when they are initially created. This makes it easy to only execute something if another object needs it:

// Watch for the first time the 'lazy-data' deferrred it bound to
promiser.watch('lazy-data', function() {
    $.ajax({
        success: function(data) {
            promiser.resolve('lazy-data', data);
        },
        error: function(xhr, text, err) {
            promiser.reject('lazy-data', xhr, text, err);
        }
    });
});

// This executes the watch handler above
promiser.done('lazy-data', function(data) {
    // do something...
});

Install

Bower

bower install promiser

NPM

npm install promiser

Setup

promiser.js works in the browser as well as the Node and AMD environments.

Usage

The promiser object can be used three ways:

Singleton

// It can be used directly
promiser.done('foo', function() { ... });

Constructor

// Create promiser objects
var p1 = new promiser;
p1 instanceof promiser; // true

Function

// Create a new plain object
var p1 = promiser();

// Extend an existing object
var p2 = promiser({});