NPM Tutorial

Title	Remark
Introduction to NPM	Learn what NPM is, its purpose, and why it’s essential for JavaScript developers.
Installing NPM	Step-by-step guide on how to install NPM on your computer.
Understanding NPM Packages	Learn what NPM packages are, how to install and use them in your projects.
Using the NPM Command Line	Explore the most common NPM commands and their functions.
Creating a package.json File	Understand the structure and importance of the package.json file in your projects.
Managing Dependencies with NPM	Learn how to manage project dependencies using NPM and keep them updated.
NPM Scripts	Automate tasks in your project with NPM scripts and learn how to run them.
Publishing an NPM Package	Learn the steps required to publish your own NPM package for others to use.
NPM Best Practices	Discover best practices for using NPM to keep your projects organized and efficient.
Troubleshooting NPM Issues	Common problems you might face with NPM and how to solve them quickly.

How to Publish Your JavaScript Library to npm

Welcome to the guide on how to create and share your own JavaScript library! With this tutorial, you will learn step by step how to write, publish, and update your library so that other people can use it.

Menu of Steps:

1. Step 1: Prepare Your Package

   • Create a folder for your library.
   • Set up your project with npm.
   • Write your library’s code.
   • Add details in the package.json file.

2. Step 2: Publish to npm

   • Create an npm account.
   • Log in to npm.
   • Publish your library to npm.

3. Step 3: Verify Installation

   • Test if others can install your library.

4. Step 4: Update Your Package

   • Change your version.
   • Publish a new version.

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Step 1: Prepare Your Package

1.1 Create a Folder for Your Project

To start, you need to create a new folder (like a box) where all your library files will go. Open your computer's terminal (it’s like a place where you type commands) and type:

mkdir my-library  # This makes a new folder called 'my-library'
cd my-library     # This opens the folder so you can start working in it

Now you’re ready to create your library!

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1.2 Set Up Your Project with npm

npm is like a big store where libraries live. To make your library ready for the store, you need to tell npm about your project. In your terminal, type:

npm init

You will see questions pop up like:

• Name: What do you want to call your library? (e.g., "my-library")
• Version: What is the first version of your library? (e.g., "1.0.0")
• Description: Describe your library in one sentence.

Just press Enter after each question. When you're done, npm will create a special file called package.json where all your answers are saved.

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1.3 Write Your Library Code

Now it’s time to write the code that does something useful! In the my-library folder, create a file called index.js. This is where the magic happens.

Write the following code inside index.js:

// index.js
module.exports = function() {
    console.log('Hello, world!');  // This prints "Hello, world!" when used
};

This is a simple library that says "Hello, world!" when someone uses it.

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1.4 Add Information to package.json

Your package.json file helps others know what your library does. Here's an example of what it should look like:

{
  "name": "potatoscript",
  "version": "1.0.0",
  "description": "A simple JavaScript library",
  "main": "index.js",
  "keywords": [
    "library",
    "npm"
  ],
  "author": "Your Name",
  "license": "MIT"
}

Replace "Your Name" with your actual name, and save the file. This is important because npm will use this information to show others what your library is about.

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Step 2: Publish to npm

2.1 Create an npm Account

Before you can publish your library, you need an npm account. Go to npmjs.com and sign up for a free account.

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2.2 Log in to npm

Once you have your account, it’s time to log in. In your terminal, type:

npm login

This will ask for:

• Username: Type your username from the npm website.
• Password: Type your password.
• Email: Type your email address.

After logging in, you're ready to publish your library!

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2.3 Publish Your Library

To put your library on npm for the world to use, type this command in your terminal:

npm publish

If everything goes well, your library will be published! Now others can use it by typing npm install potatoscript.

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Step 3: Verify Installation

After publishing, let's make sure everything works! Try installing your library into a new project:

1. Go to any folder (or make a new one) and open the terminal.
2. Type the following command:

npm install potatoscript

This will install your library so you can use it. You can also type:

npm i potatoscript

If it works, you’ll see that npm has installed your library, and you can use it in your projects!

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Step 4: Update Your Package

4.1 Update the Version

When you make changes to your library, you need to update the version number. This is how people know you’ve made new changes. In your package.json file, change the version number.

For example:

• If you fixed a bug, change the version to 1.0.1.
• If you added a new feature, change the version to 1.1.0.
• If you made big changes, change the version to 2.0.0.

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4.2 Publish a New Version

After updating your version number, run the npm publish command again to update your library on npm.

npm publish

Now everyone can use the new version!

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Final Tips

• README file: It’s always good to add a README.md file to explain what your library does and how to use it.
• Test your library: You can use tools like Jest to test your library and make sure it works well.
• Versioning: Always remember to update your version number when you make changes!

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Congratulations! 🎉 You've just created, published, and updated your own JavaScript library. Keep coding and sharing your ideas with the world!