Web Development with Nodejs NPM NVM

When building web applications using JavaScript frameworks like React or Angular, there are tools that enable the installation of these frameworks and aid in the development process. These tools are essential to be able to build, test and manage some dependencies in our projects. It is those package dependencies that we continuously need to keep up with the latest update. To update those packages, we use the NPM CLI tool, which runs on the NodeJS runtime environment.

When we need to update a package, we may face issues that a package or a new version of that package is not supported (see error below) for the current version of Node.js and that we need to update to a new version. In this article, we discuss the tools that are used to manage the software development process and how to best update NodeJS using the command line interface (CLI).

npm WARN notsup Unsupported engine for create-react-app@5.0.0: wanted: {"node":">=14"} (current: {"node":"12.16.1","npm":"6.14.4"}) npm WARN notsup Not compatible with your version of node/npm: create-react-app@5.0.0

This error message indicates that a particular required version of Node.js is not in the system and node version 14 is a dependency.

What is Node.js?

Node.js is a cross-platform JavaScript runtime environment. It is used by software engineers to build server-side and client-side web applications.  When building client applications with popular frame works like React, Angular and others, Node.JS provides the runtime environment for the JavaScript applications to run. It also enables the build and test tools that are used during the implementation effort of those applications.

JavaScript's applications are made of several libraries or packages that can be added to the project. Those libraries are mostly refereed as packages, and to install them, developers use a CLI tool to install and configure them.

What is NPM?

Node Package Manager (NPM) is a tool that runs on the NodeJS runtime environment. It comes with the installation of Node.js. Its purpose is to download and install packages for a particular project. Those packages and respective versions are tracked on a JSON file on the root folder of the project. With NPM, we can also install other CLI tools that can be specific for scaffolding startup codebase for a particular JavaScript framework. Some examples include, but not limited to, are: yeoman, create-react-app, angular CLI.

NPM has many commands, but the install command is the most basic and most important one, as this is the one that enables us to install and update packages. Let’s look at some of these commands:

Command	Description
$ npm install package-name  –save	Installs a package latest version and saves the reference the package.json file
$ npm install package-name	Installs a package but does not store any reference information
$ npm update package-name	Updates a package with a new release. NPM decides what version to select
$ npm install package-name@latest	To have better control on what version to install, we can provide the version number or latest release flag right after the package name, separated by the @ character
$ npm install -h	Shows help information on running the install command
$ npm run script-name	Runs a script command defined on the package.json for build, test, starting the project
$ npm install -g npm@next	This command is used to install the next version of NPM. The -g flag should be used to install this globally in the system

 

What is package JSON?

Package.json is a metadata file which host all the project related information like project name, licensing, authors, hosting, location and most importantly information to track project dependencies and scripts to run.

When installing NPM packages to a project, the information is saved on a file at the root of the project, package.json. This file maintains project information and all the package dependencies.  By tracking the package dependencies, a development environment can be easily created it. The developers only need to clone the repo or codebase and use NPM to download all the dependencies by typing the following command from the root folder of the project:

$ npm install

 

*Note:  package.json must exist in the same folder location where this command is typed

The script area of the package.json file provide commands that can be used to create production quality builds, test plan execution, coding standard validation and running the application. These are essential command for the day-to-day development operations and integration with CICD tools like GitHub Actions or Jenkins.

Keep Node.js Updated

With a better understanding of Node.js and the purpose of NPM for the development process, we can now discuss how to deal with situations when NPM fails to install a package because our Node.js installation is behind a few versions, and we need to upgrade it.

What is NVM?

The best way to update Node.js is by using another CLI tool, Node Version Manager (NVM). This tool enables us to manage multiple versions of Node.js in our development workspace. It is not a required tool, but it is useful because it enables us to upgrade and test the application to the latest releases, which can help us identify compatibility issues with the new runtime or NPM packages. It also enables us to downgrade to previous version to help us verify when a feature started to break.

To install NVM on Linux, we can run the following command:

$ curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.34.0/install.sh | bash

Once the tool is installed, we can run a few commands to check the current Node.js version, install a new one and switch between versions. Let us review those commands:

Command	Description
$ nvm version	Shows the selected node version
$ nvm –version	Shows the nvm cli version
$ nvm ls	Lists all the Node.js versions installed
$ nvm use version-number	Selects a Node.js version to use
$ nvm install version-number	Installs a Node.js version

 

To install a new version of Node.js, we can use the install command. This downloads and install a new version. After the version is installed, the environment should default to the new version of Node. If the environment was encountering the unsupported Node.js version error, we can run the NPM command that failed again, and since the new version is installed, it should be able to install the new package.

Conclusion

When working with JavaScript frameworks like React or Angular, the Node.js runtime environment must be installed and kept with the latest version.  When new NPM packages need to be installed on our projects, we need to make sure that they are compatible with the current version of the runtime environment, Node.js. If this is not the case, the NPM package fails to install, and we need to update the runtime with the next or latest version. Using tools like NPM and NVM, we can manage the different versions of packages and runtime respectively.  Understanding the purpose of these tools and how to use them is part of the web development process, and it should help us keep the development environment up to date.

Have you used these CLI tools before? Do you like to use visual tools instead?

Send question or comment at Twitter @ozkary

Originally published by ozkary.com