Pages with tag Asynchronous Programming

Asynchronous array operations in ES7 JavaScript async/await functions

A glaring problem with the most excellent async/await feature in JavaScript is all the existing coding structures that only work with synchronous code. In an async/await function it's trivially easy to write a simple "for" loop that contains whatever async/await calls you want. But as soon as you try "Array.forEach" with an async callback function it will fail miserably. That's because this function, like so many existing interfaces which take a callback function, assumes the callback is synchronous. Instead of waiting for the Promise to resolve, it plows on ahead executing the next iteration.

How do function(err,data) callbacks work in Node? Those new to Node programming might find the callback function pattern a little difficult to understand.  For example how does the data get into the arguments to the function call, and how does the callback function get called?
Java, Twitter, and asynchronous event driven architecture

Twitter famously launched using the then-popular Ruby on Rails web framework. Since then they suffered scalability problems which they famously made light of with the Fail Whale. Word has been that they started using Scala a while back, and it turns out they've been doing an intense study of methods to scale their service to handle the traffic volume they've been facing. A recent article on InfoQ went over some of the things they did, and surprisingly they did not use any Node.js software.

New Book: Asynchronous JavaScript with Promises, Generators and async/await The JavaScript language is changing, and among the changes are three new features which will revolutionize the way we write asynchronous code in JavaScript. The problem with the old callback-oriented asynchronous coding practice is the Callback Hell resulting from stacking callbacks within callbacks within callbacks. Between Promises, Generators and the proposed async/await feature, JavaScript programmers can largely free themselves from Callback Hell, and write clean asynchronous code that's easier to write, easier to understand, easier to maintain, and more robust.
Streamline Mocha/SuperTest REST tests with async functions

Mocha is an excellent unit testing framework for Node.js, and SuperTest is an excellent library for testing REST services. SuperTest is based on SuperAgent which makes it pretty darn easy to write code interfacing with a REST service. The problem with this combination is the test code can get pretty darn caught up in boilerplate callback functions, if you use Mocha and SuperTest the way its documented. Fortunately it's pretty easy to make SuperTest return a Promise, which then plays well with async functions, and Mocha is easily able to use an async function in a test scenario. So let's get started.

The advent of async/await for Node.js - Node.js v7 has now arrived

With today's first release of Node.js version 7, we now have async/await as a base feature of the platform. This is a significant milestone that wasn't even mentioned in the commit message. The async/await feature is so important that I'm preparing a short book to discuss JavaScript asynchronous programming patterns, that highly features async/await.

Troubles with Asynchronous code flows in JavaScript, and the async/await solution of ES-2017

Asynchronous coding is one of those powerful tools that can bite, if you're not careful. Passing around anonymous so-called "callback" functions is easy, and we do it all the time in JavaScript. Asynchronous callback functions are called, when needed, as needed, sometime in the future. The key result is that code execution is out-of-order with the order-of-appearance in the code.

Useful reading to understand the Promises, Generators and the async/await feature for Node.js/JavaScript

The long-awaited async/await feature for JavaScript promises to make our lives much easier. Instead of asynchronous JavaScript programming being tricky and error-prone, with async/await our code will look like regular synchronous code we write in other languages, but will accommodate asynchronous code execution while retaining the single-threaded nature of JavaScript. With this feature we declare async functions, and within their boundary magic occurs - we can put the "await" keyword in front of a function which produces a Promise, and automagically JavaScript will wait for the Promise to resolve and give us the result or else throw the error. What follows is a list of posts describing how to use async/await.

2016 Election Acer C720 Ad block AkashaCMS Amazon Amazon Kindle Amiga Android Anti-Fascism AntiVirus Software Apple Apple Hardware History Apple iPhone Apple iPhone Hardware April 1st Arduino ARM Compilation Astronomy Asynchronous Programming Authoritarianism Automated Social Posting Ayo.JS Bells Law Big Brother Big Finish Bitcoin Mining Black Holes Blade Runner Blockchain Blogger Blogging Books Botnet Botnets Cassette Tapes Cellphones Christopher Eccleston Chrome Chrome Apps Chromebook Chromebooks Chromebox ChromeOS CIA CitiCards Citizen Journalism Civil Liberties Clinton Cluster Computing Command Line Tools Comment Systems Computer Hardware Computer Repair Computers Cross Compilation Crouton Cryptocurrency Curiosity Rover Cyber Security Cybermen Daleks Darth Vader Data backup Data Storage Database Database Backup Databases David Tenant DDoS Botnet Detect Adblocker Developers Editors Digital Photography Diskless Booting Disqus DIY DIY Repair DNP3 Do it yourself Docker Docker MAMP Docker Swarm Doctor Who Doctor Who Paradox Drobo Drupal Drupal Themes DVD E-Books E-Readers Early Computers Election Hacks Electric Bicycles Electric Vehicles Electron Emdebian Encabulators Energy Efficiency Enterprise Node EPUB ESP8266 Ethical Curation Eurovision Event Driven Asynchronous Express Facebook Fake News Fedora VirtualBox File transfer without iTunes FireFly Fraud Freedom of Speech Gallifrey git Gitlab GMAIL Google Google Chrome Google Gnome Google+ Government Spying Great Britain Heat Loss Hibernate Hoax Science Home Automation HTTPS Human ID I2C Protocol Image Analysis Image Conversion Image Processing ImageMagick In-memory Computing InfluxDB Infrared Thermometers Insulation Internet Internet Advertising Internet Law Internet of Things Internet Policy Internet Privacy iOS Devices iPad iPhone iPhone hacking Iron Man Iternet of Things iTunes Java JavaScript JavaScript Injection JDBC John Simms Journalism Joyent Kaspersky Labs Kindle Kindle Marketplace Lets Encrypt LibreOffice Linux Linux Hints Linux Single Board Computers Logging Mac OS Mac OS X Machine Readable ID macOS MacOS X setup Make Money Online MariaDB Mars Matt Lucas MEADS Anti-Missile Mercurial Michele Gomez Micro Apartments Military Hardware Minification Minimized CSS Minimized HTML Minimized JavaScript Missy Mobile Applications MODBUS Mondas MongoDB Mongoose Monty Python MQTT Music Player Music Streaming MySQL NanoPi Nardole NASA Net Neutrality Node Web Development Node.js Node.js Database Node.js Testing Node.JS Web Development Node.x North Korea npm NY Times Online advertising Online Community Online Fraud Online Journalism Online Video Open Media Vault Open Source Governance Open Source Licenses Open Source Software OpenAPI OpenVPN Paywalls Personal Flight Peter Capaldi Photography PHP Plex Plex Media Server Political Protest Postal Service Power Control Privacy Production use Public Violence Raspberry Pi Raspberry Pi 3 Raspberry Pi Zero Recycling Refurbished Computers Remote Desktop Republicans Retro-Technology Reviews Right to Repair River Song Robotics Rocket Ships RSS News Readers rsync Russia Russia Troll Factory Russian Hacking SCADA Scheme Science Fiction Search Engine Ranking Season 1 Season 10 Season 11 Security Security Cameras Server-side JavaScript Shell Scripts Silence Simsimi Skype Social Media Social Media Warfare Social Networks Software Development Space Flight Space Ship Reuse Space Ships SpaceX Spear Phishing Spring Spring Boot SQLite3 SSD Drives SSD upgrade SSH SSH Key SSL Swagger Synchronizing Files Telescopes Terrorism The Cybermen The Daleks The Master Time-Series Database Torchwood Total Information Awareness Trump Trump Administration Trump Campaign Ubuntu UDOO Virtual Private Networks VirtualBox VLC VNC VOIP Web Applications Web Developer Resources Web Development Web Development Tools Web Marketing Website Advertising Weeping Angels WhatsApp Window Insulation Wordpress YouTube YouTube Monetization