4 mistakes that should be careful in NodeJS

Today, I would like to share about four common mistakes that should be careful when develop with NodeJS. Let’s take a look.

Blocking the Event Loop

Since Node JS comes with a single-threaded environment, no two parts of a Node JS application can run parallelly.

So, If the event loop is blocked, it causes blocking everything.

The solution is to use open-source modules like StrongOps.

StrongOps can identify and fix any delays in the event loop and prevent from blocking the event loop.

Trying to Execute Multiple Callbacks

Callbacks is used to allow asynchronous elements to communicate with each other.

However, executing the same callbacks or multiple callbacks all at once can cause interface freeze.

Therefore, it’s important to ensure you’re not continuously pressing for callbacks multiple times.

There are two ways to avoid that.

First, you can wrap the callback so you’ll be notified each time a callback is executed twice.

The second solution is to add a return before the callback to prevent invoking the same callback more than once.

Callback Hell

Callback Hell means  multiple nested callbacks that make nesting callbacks difficult and impossible to read & debug the written code.

There are many ways to keep the code easy-to-read and debug such as using promises.

A promise is basically a value returned to confirm the processing done by an asynchronous function. In simple terms, promises can be nested to make complex code look clear and easier to maintain.

Another way is to use the async module that provides a straight forward, powerful functions to work with asynchronous JavaScript.

Using Console.log for Debugging

Console.log in the NodeJS is to print almost anything to the console. When Console.log is used to debug, it restarts the server and slows down the performance of the application.

We can’t use console.log every time. So instead of console.log, we can use the Debug Library.

This is all for now.

Hope you enjoy that.

By Asahi