Getting Started with Create React App

This project was bootstrapped with Create React App.

What Does This Package Do?

This package is a React project bootstrapped with Create React App, designed for building modern web applications. In addition to the standard features provided by Create React App, this project includes a utility for comparing two package-lock.json files. This utility helps identify differences between dependencies, versions, and other metadata in two separate package-lock.json files, which can be useful for maintaining consistency across different environments or branches.

Comparing Two package-lock.json Files

Task: Compare Two package-lock.json Files

This project includes a script that allows you to compare two different package-lock.json files. The files can be located in different directories, making it easy to identify any differences between them. This can be particularly useful when:

• Comparing the dependency trees of different branches.
• Checking for discrepancies between development and production environments.

How to Use

To compare two package-lock.json files, follow these steps:

1. Ensure that both package-lock.json files you want to compare are available on your local system.

2. Run the comparison script by using the following command:

   npm run compare-lock-files --path1=/path/to/first/package-lock.json --path2=/path/to/second/package-lock.json
   
   

Prerequisites

Before you begin, ensure you have met the following requirements:

• You have installed Node.js and npm.
• You have a basic understanding of JavaScript, React, and web development.

Project Structure

A brief overview of the project's structure:

my-app/
├── node_modules/
├── public/
├── src/
│   ├── components/
│   ├── assets/
│   ├── App.js
│   ├── index.js
│   └── ...
├── .gitignore
├── package.json
├── README.md
└── ...

• public/: Static files like index.html, images, and other assets.
• src/: Main source code, including React components, styles, and utilities.
• package.json: Project metadata and dependencies.
• .gitignore: Files and directories ignored by Git.

Available Scripts

In the project directory, you can run:

npm install

Installs the necessary dependencies for the project. Run this command before starting or building the project.

npm start

Runs the app in development mode.Open http://localhost:3000 to view it in your browser.

• The page will reload when you make changes to the code.
• Lint errors and warnings will appear in the console.

npm test

Launches the test runner in interactive watch mode.Refer to the running tests section for more details.

• Test files are generally placed under the src/ directory with the .test.js or .spec.js extension.

npm run build

Builds the app for production in the build folder.This command optimizes the React app for the best performance:

• React is bundled in production mode.
• The build output is minified, and filenames include hashes for caching.

Your app is now ready for deployment!

For more details, refer to the deployment section.

npm run eject

Warning: Ejection is a one-way operation! Once you eject, you cannot go back!

This command gives you full control over the project configuration by copying all dependencies and configurations into your project. You should only eject if necessary for advanced customizations.

npm run lint

Runs the linter to check for code style and syntax errors.Configure the linter in .eslintrc.js according to your project's needs.

npm run format

Formats the code according to the rules specified in .prettierrc.This ensures a consistent code style across the project.

Configuration

Environment Variables

Environment variables can be configured in the .env file at the root of the project:

REACT_APP_API_URL=https://api.example.com

Access these variables in your React code using process.env.REACT_APP_API_URL.

Proxy Setup

To avoid CORS issues during development, you can set up a proxy in the package.json file:

"proxy": "http://localhost:5000"

Code Splitting

Split your code into smaller bundles for improved performance.See the code splitting documentation.

Analyzing Bundle Size

Use source-map-explorer to analyze the bundle size:

npm install -g source-map-explorer
npm run build
npx source-map-explorer 'build/static/js/*.js'

Refer to the analyzing bundle size guide for more details.

Making a Progressive Web App (PWA)

Transform your app into a PWA by following the PWA guide.

Advanced Configuration

Refer to the advanced configuration section for additional setup options, such as modifying Webpack or Babel configurations.

Deployment

Your app can be deployed to various platforms such as GitHub Pages, Netlify, Vercel, or Heroku.Refer to the deployment documentation for detailed instructions on deploying your app.

Continuous Integration

You can set up Continuous Integration (CI) to automate testing and deployment:

• GitHub Actions: Use workflows to automate tests.
• Travis CI: Integrate your repository for automated testing and deployment.

Troubleshooting

npm run build fails to minify

If the build fails due to minification issues, refer to the troubleshooting guide for potential solutions.

Common Issues

• Module not found: Ensure that all dependencies are correctly installed by running npm install.
• CORS errors: Set up a proxy or configure the server to allow CORS.

Learn More

To learn more about React and related technologies:

• Create React App documentation
• React documentation
• JavaScript ES6+
• Node.js
• npm