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7 Best Ways to Debug Node.js Application Code

7 Best Ways to Debug Node.js Application Code

Kanika's photo
·Nov 23, 2022·

7 min read

Table of contents

If you are one of those who think this is how pros debug Node.js code- console.log(‘—’).

Uhhh!!! That’s not it.

To thoroughly debug Node.js code, you’ll need more than just the console.log() function.

Software developers spend their days writing code, and they keep developing it as long as it compiles and works well.

However, people may become frustrated if the code fails to function, and if the code is more than 200 lines, it is either impossible or extremely time-consuming to make changes to the code by analyzing it line by line.

Tracing a coding issue back to its cause in Node.js development can save a lot of time throughout a project. However, when a code grows in complexity, it gets increasingly difficult to do so efficiently.

But debugging Node.js application code shouldn’t be this hard.

With this blog, let’s go beyond just logging everywhere in your code and see simple ways to debug Node.js code like a pro.

What is Debugging?

Debugging means discovering and removing those shady bugs, faults, or inconsistencies in code. Debugging enables developers to rectify those problems and ensure that the applications run successfully in compliance with the required standards.

Changing a single character or introducing a new line of code is often enough to fix a bug.

But it’s easier said than done.

Fixing a bug is simple but finding one in the maze of code is a different story. Developers often spend a lot of time just finding what’s wrong.

Well, say no to wasting your time. We have compiled some excellent ways to help you find and fix bugs.

Let’s hop on to ways to debug Node.js code.

ways to debug nodejs application code (1).png

Here Are The 7 Best Ways To Debug Node.js Code

The process of debugging Node.js can be carried out in various ways. These are some of the best ways, with a bonus in the end, which will help you debug the node application in minutes.

1. Environment Variables

The environment variables of the host operating system can be used to modify Node.js application settings. When debugging, the most common is NODE_ENV, which is normally set to development.

On Linux/macOS, environment variables can be set easily.

NODE_DEBUG enables debugging messages via the Node.js util.debuglog, but you should also review the documentation of your key modules and frameworks to learn about additional possibilities.

It is worth noting that environment variables can also be saved to an a.env file. As an example:

Node debugging 1.jpg

2. Explore Console Debugging

Oh, here is an all-time favorite. As I previously stated, most users associate Node.js debugging with the console.log() function.

Most JavaScript developers are familiar with the console.log() method. If not, it will simply print a string or an object. Most developers, however, are unaware that the console object contains many useful methods that are sometimes missed.

Please allow me to show you a few of them.


By invoking, you can create a new collection of JavaScript console logs (). This will group all of your logs in the browser. Call console.groupEnd() to exit the current group.

b. console.table

The next one on the list is console.table(). It performs exactly what you’d expect: it takes an array or an object and returns an ASCII table.

Node debugging 2.jpg

Code source

This is especially beneficial for long or large objects with many properties, as it adds structure and improves readability.

c. console.dir()

The first takes an object, but the second takes a set of alternatives. console.dir() allows you to specify the depth of your console login.

If you’ve ever tried to console log a native Node.js object and received a massive output, you know how difficult it is to read.

This object will add a structure to make it easier for you to comprehend. For example:

Node debug 3.jpg

> Code Source


Debug node application.png

3. Use Debugger Statements

The debugger statement is a straightforward way to begin debugging Node.js application. If the developer tools are open, a debugger statement pauses the execution of the code in the browser.

But as Node.js lacks a developer console, the same would have to be accomplished through Node.js’ inspect. An interactive debugger will now appear, allowing you to step through the code’s execution.

This is a simple debugging solution for a small Node.js application. For extensive debugging, you’ll need a more powerful tool.

4. Conduct Log Aggregation

It is vital to debug an application locally, in the same manner, it would debug in production. One of these tools is logging into your remote server to view the console logs, similar to those on your local system.

Although it is a time-consuming process, log aggregation tools are always available. These technologies collect logs from running applications and store them in a central location. They make parsing and viewing logs easy.

Various logging libraries are also available for formatting logs and sending them to a centralized log aggregator. This can be a helpful strategy to debug Node.js applications if done correctly.

5. Debug Node.js Application using Postman

The debugging tools we’ve discussed thus far will only work if you run your product as your customers would. Building RESTful APIs is a typical application for Node.js.

Postman allows you to build API requests and send them out with the click of a button. Postman is a tiny application that lets you create, save, and execute API commands.

Debug nodejs.png

Postman has recently advanced, with the ability to pre- and post-script. In layman’s terms, you can perform a series of linked commands and also feed save the values for future responses.

If you’re creating complicated RESTful APIs with Node.js, Postman is your holy grail.

6. Debugging Memory Leaks

Proper memory allocation is crucial in any Node.js application. A memory leak is a memory allocation issue that occurs when memory is inappropriately cleaned up.

This could cause the application to consume a large amount of memory, leading to the application running out of memory and eventually crashing down.

Memory leaks in JavaScript can be caused by global variables, closures, and call-back functions, among other things. Debugging memory leaks is, therefore, equally important.

Using the inspect tag and viewing the memory tab, you may analyze your memory usage in the Node.js application and find memory leaks.

7. Debug in VS Code

If you thought browsing your code was cool, you’ll love this: some IDEs offer the inspect flag, which allows you to do remote debugging without leaving the IDE.

To debug, add an inspector to your node process and add it to the WebSocket you’ve created.

Visual Studio Code includes debugging as its’ core feature. The debugging architecture of VS Code enables extension authors to easily incorporate existing debuggers into VS Code while maintaining a common user interface.

But this VS Code extension works only on the local laptop, not the server, where the customers face errors.

Want to know a way where you don’t only capture or reproduce errors but also debug those in real-time?

You know there is a way you can do all these in minutes?

Yes, you heard it right you can debug and fix your node.js code within minutes.

8. Bonus Tip: Using Debugging Tools Like Errsole

This isn’t a tip, but a tool that can make debugging easy for you.

Errsole records all errors in your Node.js application and HTTP calls that caused these errors. Errsole will not only show you what errors have occurred but also investigate where and why they occurred.

With Errsole you can:

  • Capture HTTP & Uncaught errors.
  • View the source of all errors.
  • Manage all environment errors under one location.
  • Reproduce errors with a click and in the same environment.
  • Debug your server code in real time.

And just like that, the difficult work of finding and fixing your Node.js errors has been simplified.

Wrapping Up!

Keep in mind that- There are better and more efficient methods to debug Node.js applications. Use them- your sanity will thank you.

Hopefully, this post has piqued your interest in debugging Node.js applications and will help you get started on the road to successful application development.

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