Promise

Require about 150 lines of javascript code to utilize Promise class for implementing asynchronous processes with chaining, series and joining capabilities.

js-promise supports AMD loaders.

package.json

{
  "dependencies": {
    "js-promise": "*"
  }
}

Sample usage

var Promise = require("js-promise");

function myTimeout(ms, logMsg){
    return new Promise(function(onSuccess, onError){
        setTimeout(function(){
                console.info(logMsg || ("-- Timeout ended on: " + (new Date()).toISOString()));
                onSuccess(ms);
            },
            ms
        );
    });
}

var startTime = Date.now();

console.log("Testing chains of (1+2+3+5+6)=17 seconds on " + (new Date()).toISOString());

myTimeout(1000)
.then(function(delay){
        console.log("Done " + delay + " ms!");
        return myTimeout(2000);
    }
).then(function(delay){
        console.log("Done " + delay + " ms!");
        return myTimeout(3000);
    }
).then(function(delay){
        console.log("Done " + delay + " ms!");
        return testJoin();
    }
).then(function(){
        return testSeries();
    }
).done(function(){
        var totalSeconds = ( Date.now() - startTime ) / 1000;
        console.log("Test Passed! in " + totalSeconds + " Seconds, expected: 17");
    }
);

function testJoin() {
    console.log("Waiting for 3 joined promises to finishes in (2|1|5)=5 seconds on:" + (new Date()).toISOString());
    return Promise.join([
        myTimeout(2000),
        myTimeout(1000),
        myTimeout(5000),
    ]).then(function(){
        console.log("Done Promise.join on: " + (new Date()).toISOString());
    })
}

function testSeries() {
    console.log("Testing a series of 3 timeouts (2+1+3) seconds total 6 ");
    return Promise.series([
        function() {
            return myTimeout(2000);
        },
        function() {
            return myTimeout(1000);
        },
        function() {
            return myTimeout(3000);
        }
    ]).then(function(result){
        console.log("Promise.series result = " + JSON.stringify(result));
        console.log("Done Promise.series on " + (new Date()).toISOString());
    })
}