Angular – Project File Structure Hierarchy

The folder structure of a default Angular project, created using the Angular CLI (ng new), is organized for scalability and maintainability. Here’s an overview:

1. Root Directory Structure

project-name/
│
├── e2e/                  # End-to-end testing setup
├── node_modules/         # Installed npm packages
├── src/                  # Application source code
├── .editorconfig         # Editor configuration for consistent coding styles
├── .gitignore            # Files and directories to ignore in Git
├── angular.json          # Angular CLI configuration
├── package.json          # Project dependencies and scripts
├── package-lock.json     # Dependency tree for consistent installs
├── README.md             # Project description and instructions
├── tsconfig.json         # TypeScript configuration
└── tslint.json           # (Optional) Linting configuration for TypeScript (deprecated in newer versions)

2. Key Folders in Detail

a. src/
Contains the application’s source code.

src/
│
├── app/                  # Main application folder
├── assets/               # Static files (images, icons, etc.)
├── environments/         # Environment-specific settings
├── index.html            # Main HTML file
├── main.ts               # Application entry point
├── polyfills.ts          # Polyfills for browser compatibility
├── styles.css            # Global styles
├── test.ts               # Test setup for unit tests
└── favicon.ico           # Application favicon

b. app/
Contains the core application code, including components, modules, and services.

app/
│
├── app.component.ts      # Root component logic
├── app.component.html    # Root component template
├── app.component.css     # Root component styles
├── app.module.ts         # Root module
└── additional-feature/   # (Generated folders for features)

3. Detailed Explanation

app/:

• Houses the core logic of your Angular application.
• Organized by modules and features for scalability.
• Each feature can have its own folder with components, services, and templates.

assets/:

• Stores static files such as images, fonts, and other resources.
• Automatically copied to the dist folder during build.

environments/:

• Contains environment-specific configurations:
  • environment.ts: Default environment settings.
  • environment.prod.ts: Production environment settings.
• Used to manage settings like API endpoints for different stages (development, production).

index.html:

• The single HTML file that Angular uses to bootstrap the application.
• Contains the element where the application is rendered.

main.ts:

• The entry point for the Angular application.
• Bootstraps the root module (AppModule).

styles.css:

• Global styles for the entire application.
• Can be replaced with SCSS or other preprocessors.

angular.json:

• Configuration file for the Angular CLI.
• Specifies project settings, build options, test configurations, etc.

package.json:

• Lists dependencies, devDependencies, and npm scripts.
• Common scripts:
  • ng serve: Start the development server.
  • ng build: Build the application.
  • ng test: Run unit tests.

4. Folder Structure Best Practices
   Feature-Based Organization: Group related components, services, and modules by feature. Example:

app/
├── feature1/
│   ├── feature1.component.ts
│   ├── feature1.service.ts
│   └── feature1.module.ts
└── feature2/
    ├── feature2.component.ts
    ├── feature2.service.ts
    └── feature2.module.ts

Shared Folder:

Use a shared/ folder for reusable components, directives, and pipes.
Core Module: Use a core/ module for singleton services like authentication or interceptors.