When you install using npm
a package into your node_modules
folder, or also globally, how do you use it in your Node code?
Say you install lodash
, the popular JavaScript utility library, using
npm install lodash
This is going to install the package in the local node_modules
folder.
To use it in your code, you just need to import it into your program using require
:
const _ = require('lodash')
What if your package is an executable?
In this case, it will put the executable file under the node_modules/.bin/
folder.
One easy way to demonstrate this is cowsay.
The cowsay package provides a command line program that can be executed to make a cow say something (and other animals as well 🦊).
When you install the package using npm install cowsay
, it will install itself and a few dependencies in the node_modules folder:
There is a hidden .bin folder, which contains symbolic links to the cowsay binaries:
How do you execute those?
You can of course type ./node_modules/.bin/cowsay
to run it, and it works, but npx, included in the recent versions of npm (since 5.2), is a much better option. You just run:
npx cowsay
and npx will find the package location.
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More node tutorials:
- An introduction to the npm package manager
- Introduction to Node.js
- HTTP requests using Axios
- Where to host a Node.js app
- Interact with the Google Analytics API using Node.js
- The npx Node Package Runner
- The package.json guide
- Where does npm install the packages?
- How to update Node.js
- How to use or execute a package installed using npm
- The package-lock.json file
- Semantic Versioning using npm
- Should you commit the node_modules folder to Git?
- Update all the Node dependencies to their latest version
- Parsing JSON with Node.js
- Find the installed version of an npm package
- Node.js Streams
- Install an older version of an npm package
- Get the current folder in Node
- How to log an object in Node
- Expose functionality from a Node file using exports
- Differences between Node and the Browser
- Make an HTTP POST request using Node
- Get HTTP request body data using Node
- Node Buffers
- A brief history of Node.js
- How to install Node.js
- How much JavaScript do you need to know to use Node?
- How to use the Node.js REPL
- Node, accept arguments from the command line
- Output to the command line using Node
- Accept input from the command line in Node
- Uninstalling npm packages with `npm uninstall`
- npm global or local packages
- npm dependencies and devDependencies
- The Node.js Event Loop
- Understanding process.nextTick()
- Understanding setImmediate()
- The Node Event emitter
- Build an HTTP Server
- Making HTTP requests with Node
- The Node fs module
- HTTP requests in Node using Axios
- Reading files with Node
- Node File Paths
- Writing files with Node
- Node file stats
- Working with file descriptors in Node
- Working with folders in Node
- The Node path module
- The Node http module
- Using WebSockets with Node.js
- The basics of working with MySQL and Node
- Error handling in Node.js
- The Pug Guide
- How to read environment variables from Node.js
- How to exit from a Node.js program
- The Node os module
- The Node events module
- Node, the difference between development and production
- How to check if a file exists in Node.js
- How to create an empty file in Node.js
- How to remove a file with Node.js
- How to get the last updated date of a file using Node.js
- How to determine if a date is today in JavaScript
- How to write a JSON object to file in Node.js
- Why should you use Node.js in your next project?
- Run a web server from any folder
- How to use MongoDB with Node.js
- Use the Chrome DevTools to debug a Node.js app
- What is pnpm?
- The Node.js Runtime v8 options list
- How to fix the "Missing write access" error when using npm
- How to enable ES Modules in Node.js
- How to spawn a child process with Node.js
- How to get both parsed body and raw body in Express
- How to handle file uploads in Node.js
- What are peer dependencies in a Node module?
- How to write a CSV file with Node.js
- How to read a CSV file with Node.js
- The Node Core Modules
- Incrementing multiple folders numbers at once using Node.js
- How to print a canvas to a data URL
- How to create and save an image with Node.js and Canvas
- How to download an image using Node.js
- How to mass rename files in Node.js
- How to get the names of all the files in a folder in Node
- How to use promises and await with Node.js callback-based functions
- How to test an npm package locally
- How to check the current Node.js version at runtime
- How to use Sequelize to interact with PostgreSQL
- Serve an HTML page using Node.js
- How to solve the `util.pump is not a function` error in Node.js