How to Enable npm

npm (Node Package Manager) is Node.js's package management tool and its default package manager. It is used to install, share, and manage JavaScript packages and is one of the largest open-source libraries globally. Using npm can help developers easily manage project dependencies and enhance development efficiency.

Enabling npm

Node.js installed through ServBay comes with npm enabled by default. If you find that npm is not enabled or needs updating, you can follow these steps.

Confirming npm Installation

1. Open the terminal and enter the following command to check the npm version number:

   npm -v

   Example output:

   9.1.0

Updating npm

If you need to update npm, you can update it with the following command:

npm install -g npm

Confirm the version number again:

npm -v

Benefits of Using npm

The main advantage of npm is its globally largest open-source library and convenient package management capabilities. Here are some practical examples of using npm:

Initializing a Project

Use npm to initialize a new Node.js project:

npm init

This will guide you to create a new package.json file containing basic information and dependencies of the project.

Installing Dependencies

Use npm to install project dependencies:

npm install

This will install all dependencies based on the package.json file.

Adding a Dependency

Add a new dependency package:

npm install lodash --save

This will install the lodash package and update the package.json file.

Removing a Dependency

Remove a dependency package:

npm uninstall lodash --save

This will remove the lodash package from the project and update the package.json file.

Updating Dependencies

Update all dependencies in the project:

npm update

Using npm Scripts

npm allows defining scripts in the package.json file, making it convenient to execute common commands. For example, add the following scripts to the package.json file:

"scripts": {
  "start": "node app.js",
  "test": "mocha"
}

Then you can run these scripts with the following commands:

npm start
npm test

Common Commands

• Install a Global Package:

  npm install -g <package-name>

  For example, install nodemon:

  npm install -g nodemon

• View Global Packages:

  npm list -g --depth=0

• Clean Cache:

  npm cache clean --force

By using npm, developers can easily manage project dependencies, quickly install and update packages, and thus improve overall development efficiency.