Javascript promises short example

promises-example.js

function one(){
	var promise = new Promise(function(resolve, reject){
		setTimeout(function(){
			console.log(1)
			resolve()
		}, 998)
	})
	return promise
}

function two(){
	var promise = new Promise(function(resolve, reject){
		setTimeout(function(){
			console.log(2)
			resolve("two-param")
		}, 999)
	})

	return promise
}

function three(param){
	var promise = new Promise(function(resolve, reject){
		setTimeout(function(){
			console.log(3)
			console.log("Receving param from function two() ", param);
			resolve()
		}, 1000)
	})

	return promise
}

function four(){
	var promise = new Promise(function(resolve, reject){
		setTimeout(function(){
			console.log(4)
			resolve()
		}, 900)
	})

	return promise
}

function five(){
	var promise = new Promise(function(resolve, reject){
		setTimeout(function(){
			console.log(5)
			reject("Something wrong...")
		}, 995)
	})

	return promise
}

function six(){
	var promise = new Promise(function(resolve, reject){
		setTimeout(function(){
			console.log(6)
			resolve()
		}, 800)
	})

	return promise
}

function errorHandle(err){
	console.log(err)
}

one()
	.then(two)
	.then(three)
	.then(four)
	.then(five)
	.then(six)
	.catch(errorHandle)