How to create NodeJS custom libraries

Hello 👋🏼,

My name is Andrei, I am a Senior NodeJS Developer & #AWS Architect Consultant / Contractor / Freelancer. 👨🏻💻

This post will guide you on creating #NodeJS custom libraries for your projects. 😊___________________

Prerequisites:

• Entry level 👶 knowledge of Javascript

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What is NodeJS? What is npm? 👀

Node.js is a free, open-sourced, cross-platform JavaScript run-time environment that lets developers write command line tools and server-side scripts outside of a browser. 🚀 (ref: https://nodejs.dev/ )

#npm is installed with Node.js, it is the largest software registry. The name npm (Node Package Manager) stems from when npm was first created as a package manager for Node.js. (ref: https://www.w3schools.com/whatis/whatis_npm.asp)

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Resources

• Hello World Application: link 💻
• Logger Custom Library: link 📚

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Hello World Application 💻

Okay, so first things first 📌

npm init        

The application code is simple - the sum of two numbers received as input arguments.

Application Run

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Library's content 📚

Inside the #library, you can add code that can be used in multiple nodeJS projects (multiple #lambdas on AWS). 🚀🚀🚀

For the library repository, we will do the npm init again.

As of now, the sample library includes the sum function and a new logger (winston 😎) as an external library, in fact, it is present inside the package.json

In order to create a version of the library, you can create a release 🎁

Once the code is pushed on #GitHub we can update the #package.json of the hello world application in order to use the library functions. 💪

If you want to use the code from a feature branch, you need to replace the tag (v1.0.0) with the branch name (feature/implement-library). 😌

Now, let’s run npm i and update the code with our custom library.

Now if we run the application again, we will use the methods defined inside the library. 🥳

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That’s it! A simple #NodeJS hello world application using a custom #library! 🎉

If you need any help or considerations, feel free to drop me a message 📩