Node.js
- Getting started with Node.js
- Awesome Book
- Awesome Community
- Awesome Course
- Awesome Tutorial
- Awesome YouTube
- Arduino communication with nodeJs
- async.js
- async.each(To handle array of data efficiently)
- async.series(To handle events one by one)
- async.times(To handle for loop in better way)
- Parallel : multi-tasking
- Series : independent mono-tasking
- Waterfall : dependent mono-tasking
- Async/Await
- Asynchronous programming
- Autoreload on changes
- Avoid callback hell
- Bluebird Promises
- Callback to Promise
- Cassandra Integration
- CLI
- Client-server communication
- Cluster Module
- Connect to Mongodb
- Creating a Node.js Library that Supports Both Promises and Error-First Callbacks
- Creating API's with Node.js
- csv parser in node js
- Database (MongoDB with Mongoose)
- Debugging Node.js application
- Deliver HTML or any other sort of file
- Dependency Injection
- Deploying Node.js application without downtime.
- Deploying Node.js applications in production
- ECMAScript 2015 (ES6) with Node.js
- Environment
- Event Emitters
- Eventloop
- Exception handling
- Executing files or commands with Child Processes
- Exporting and Consuming Modules
- Exporting and Importing Module in node.js
- File upload
- Filesystem I/O
- Getting started with Nodes profiling
- Good coding style
- Graceful Shutdown
- grunt
- Hack
- Handling POST request in Node.js
- How modules are loaded
- http
- Installing Node.js
- Interacting with Console
- Keep a node application constantly running
- Koa Framework v2
- Lodash
- Loopback - REST Based connector
- metalsmith
- Mongodb integration
- MongoDB Integration for Node.js/Express.js
- Mongoose Library
- MSSQL Intergration
- Multithreading
- Mysql Connection Pool
- MySQL integration
- N-API
- Node JS Localization
- Node server without framework
- Node.js (express.js) with angular.js Sample code
- Node.JS and MongoDB.
- Node.js Architecture & Inner Workings
- Node.js code for STDIN and STDOUT without using any library
- Node.js Design Fundamental
- Node.js Error Management
- Node.js Performance
- Node.js v6 New Features and Improvement
- Node.js with CORS
- Node.JS with ES6
- Node.js with Oracle
- NodeJS Beginner Guide
- NodeJS Frameworks
- Nodejs History
- NodeJs Routing
- NodeJS with Redis
- npm
- nvm - Node Version Manager
- OAuth 2.0
- package.json
- Parsing command line arguments
- Passport integration
- passport.js
- Performance challenges
- PostgreSQL integration
- Project Structure
- Push notifications
- Readline
- Remote Debugging in Node.JS
- Require()
- Restful API Design: Best Practices
- Route-Controller-Service structure for ExpressJS
- Routing ajax requests with Express.JS
- Running node.js as a service
- Securing Node.js applications
- Send Web Notification
- Sending a file stream to client
- Sequelize.js
- Simple REST based CRUD API
- Socket.io communication
- Synchronous vs Asynchronous programming in nodejs
- TCP Sockets
- Template frameworks
- Uninstalling Node.js
- Unit testing frameworks
- Use Cases of Node.js
- Using Browserfiy to resolve 'required' error with browsers
- Using IISNode to host Node.js Web Apps in IIS
- Using Streams
- Using WebSocket's with Node.JS
- Web Apps With Express
- Windows authentication under node.js
- Yarn Package Manager
Node.js async.js
Syntax
-
Each callback must be written with this syntax:
-
function callback(err, result [, arg1[, ...]])
-
This way, you are forced to return the error first, and can't ignore handling them later on.
nullis the convention in absence of errors -
callback(null, myResult);
-
Your callbacks can contain more arguments than err and result, but it's useful only for a specific set of functions (waterfall, seq, ...)
-
callback(null, myResult, myCustomArgument);
-
And, of course, send errors. You must do it, and handle errors (or at least log them).
-
callback(err);
async.js Related Examples
- async.each(To handle array of data efficiently)
- async.series(To handle events one by one)
- async.times(To handle for loop in better way)
- Parallel : multi-tasking
- Series : independent mono-tasking
- Waterfall : dependent mono-tasking
