sync-node

This tiny node module will help you to make your tasks synchronous without blocking the main JavaScript thread.

$ npm install sync-node

The problem

JavaScript is single threaded; thus forces you to write asynchronous code. But there are scenarios where we may want some functions or tasks to run one after another. Promises are one of the best things to be used in these scenarios, but if you have a number of tasks like that, well putting .then() one after another will certainly make an ugly looking code.

In the other hand, there are libraries which makes things purely synchronous. But the problem with that is, JavaScript has only one thread, blocking which will paralyse your application for a while.

The solution

This plugin works with a middle way, where it doesn't block anything, but still makes things synchronous.

The concept here is to provide you with a job queue, where you can push your functions one after another and they will be executed in the sequence they pushed. If a function is asynchronous, the next one of that will not be run till it gets resolved.

Example

    var SN = require('sync-node');
    var pn = SN.createQueue();
    pn.pushJob(function(){
        return new Promise(function (resolve, reject) {
            //I am using setTimeout to make the function async
            setTimeout(function() {
                console.log("I am supposed to be first!!");
                resolve("fox");
            }, 5000);
    
        })
    });
    pn.pushJob(function(res){
            console.log("I should come second!! Previous response was "+res);
    });
    
    pn.pushJob(function(){
        return new Promise(function (resolve, reject) {
            setTimeout(function() {
                console.log("Yes, I am third!!");
                resolve();
            }, 1000);
    
        })
    });
    
    
    pn.pushJob(function(){
            console.log("Oh no.. I'm last!!");
    });

Note

If you have any asynchronous function, than it must return a promise, else the queue will not come to know when the actual execution of that function is finished. A better tutorial can be found in Void Canvas.