Promises Chaining Example

promises.js

/* --------------------------------
get user id

get commit history

get first commit

get first file name

-------------------------------- */
'use strict';

function getUserId(text){
  return new Promise(function(resolve){
     setTimeout(function(){
     	text+= 'For user = shidhin and ';
     	resolve(['shidhin', text]);
     }, 1000);
  });
}

function getCommitHistory(args){
  var 
  	userId = args[0],
	text = args[1];	
  return new Promise(function(resolve){
     setTimeout(function(){
     	text+='for commit = adsfasd879897 and ';
     	resolve(['adsfasd879897', text]);
     }, 1000);
  });
}

function getFirstCommit(args){
  var 
  	commitHistory = args[0],
	text = args[1];
  return new Promise(function(resolve){
     setTimeout(function(){
     	text+= 'for firstCommit = '+ commitHistory.slice(3,12);
     	resolve([commitHistory.slice(3,12), text]);
     }, 1000);
  });
}

function getFirstFilename(args){
	var 
  	firstCommit = args[0],
	text = args[1];
  return new Promise(function(resolve){
     setTimeout(function(){
     	text+='for filename = fileName_'+firstCommit+'.txt';
     	resolve(['fileName_'+firstCommit+'.txt', text]);
     }, 1000);
  });
}

getUserId('Hey, ')
	.then(getCommitHistory)
	.then(getFirstCommit)
	.then(getFirstFilename)
	.then(function(args){
		console.log(args[0]);
		console.log(args[1]);
	});