We are going to have a look at how you can test your React Components and your Redux reducers and actions.

This article will demonstrate how to test JavaScript files in NodeJS using the libraries Sinon, Mocha and Chai. Sinon is often installed together with Mocha and Chai, but it is not required.

There are many strategies to scale your application: Cloning Decomposing Splitting The cluster module helps you to scale your code on one system that has many CPU cores. The idea is: You have one master process and clone your code by forking as many worker processes as you have CPU cores in your system. This […]

Streams are collections of data that might not be available all at once and don’t have to fit in memory all at once. For example if you want to serve a file that is 1GB over HTTP you would create a stream instead of reading the file using readFileSync. A Stream can be piped directly […]

Check if a file exists Here are a couple of sync and async ways to check if a file exists via NodeJS. Reading files within a directory Watching files

What you can achieve are things like: Create a server Work with streamed data Make API calls Creating an HTTP server We create an HTTP server on port 8080 and respond to any request with a ‘Hello there!’: IncomingMessage extends two interfaces EventEmitter and ReadableStream which allow us to listen to events and process streams, […]

Slow I/O operations such as accessing disk and network resources are handled via Node’s Event Loop. The Event Loop is started once you run a node script and exits once there are no more callbacks to process. Heap and Stack V8 is node’s runtime engine and mainly consists of a Heap and a Stack. The […]

There are a couple of ways to execute files and commands, but all use the module child_process. For example you have child_process.exec creates a shell and also buffers the whole command’s generated output and sends it to a callback function. So use it only if the output is not too big. child_process.execFile runs a file […]

Setting env to debug modules Setting NODE_DEBUG=”http” will output debug info to the console for Node’s http module. Use a comma seperated list to debug more modules at the same time. You can adjust NODE_PATH to tell Node where to look for modules. Setting and reading custom env You can define custom env variables in […]

Require or import modules In the REPL all node modules are already present so you do not have to explicitly require() them first. But when you write your own files you can must choose between one of two options: or use ES6-style, but you have to use .mjs file extension. Node Modules There are a […]