Research (Implementing Backend into Angular)

How to implement a Nest JS backend with an

so itoh lang pinaka malapit kong nakita paano mag implement ng backend sa
angular

NestJS Backend
• NestJS is a progressive Node.js framework for building backends, inspired by
Angular.

• To create a NestJS backend, use the nest new command followed by the application
name.

• The generated backend will have a familiar file structure, including modules,
services, and controllers.

• To create a dedicated players endpoint, use the nest g module players and nest g
controller players commands.
 • Decorate the controller method with @Get() to make it accessible over REST.

• For data access, create a service using nest g service players.

• Inject the service into the controller and call its method instead of returning a hard-
coded array.

• To enable CORS for development purposes, call app.enableCors() in the main.ts

• To start the backend, run npm start in the backend directory.

Angular Frontend
• To start the frontend, open a new terminal tab and scaffold a new Angular application
using ng new players-frontend.

• Install the @nestjs/common package in the frontend project to use NestJS decorators.

• Create a PlayerService in the frontend project to handle player data.

• Create a PlayersComponent to display the list of players.

• Use the HttpClient service to make HTTP requests to the backend API.

• Run ng serve in the frontend directory to start the frontend application.

Angular CLI
• The Angular CLI (Command Line Interface) can be installed globally using npm i -
g @angular/cli.

• The ng new command can be used to scaffold a new Angular application.

• The ng generate command can be used to generate various building blocks for an
Angular application, such as modules, components, and services.

Comparison
• Angular uses components, while Nest uses controllers.
ChatGPT
Implementing a backend into an Angular application involves setting up a server-side
environment to handle data storage, retrieval, and business logic. Here's a general guide on how
to implement a backend into an Angular application:

1. **Choose a Backend Technology**:

- Common backend technologies include Node.js with frameworks like Express.js, Django
(Python), Ruby on Rails, Laravel (PHP), or ASP.NET Core (C#). Choose one that best fits your
project requirements and your team's expertise.

2. **Set Up Your Backend Project**:

- Install the necessary dependencies and initialize your backend project.

- For Node.js with Express.js, you can use npm to initialize a new project: `npm init`.

- For other technologies, follow their respective documentation for project setup.

3. **Define API Endpoints**:

- Design your backend API endpoints to handle data CRUD operations (Create, Read, Update,
Delete).

- Use RESTful principles or GraphQL depending on your project requirements.

- Define routes for handling HTTP requests such as GET, POST, PUT, DELETE.

4. **Implement Database Integration**:

- Choose a suitable database system like MongoDB, MySQL, PostgreSQL, SQLite, etc.

- Set up database connections and implement data models/schema.

- Use Object-Relational Mapping (ORM) or Object-Document Mapping (ODM) libraries if

- Implement user authentication and authorization mechanisms if your application requires user
login and access control.

- Use techniques like JSON Web Tokens (JWT), OAuth, or session-based authentication.

6. **Handle File Uploads (if required)**:

- Implement functionality to handle file uploads if your application needs to deal with files
(images, documents, etc.).

- Use libraries like multer (Node.js) for handling multipart/form-data.

7. **Middleware and Error Handling**:

- Implement middleware functions for common tasks like logging, request parsing, etc.

- Set up error handling middleware to handle exceptions and errors gracefully.

8. **Test Your Backend APIs**:

- Use tools like Postman, curl, or Swagger for testing your backend APIs to ensure they work
as expected.

9. **CORS (Cross-Origin Resource Sharing)**:

- Configure CORS settings on your backend server to allow requests from your Angular
application's domain.

10. **Deploy Your Backend**:

- Deploy your backend application to a suitable hosting provider or server.

- Ensure proper security measures are in place, such as HTTPS encryption and firewall
configurations.
11. **Integrate Backend with Angular**:

- Use Angular's HttpClient module to make HTTP requests to your backend APIs.

- Implement services in Angular to encapsulate API calls and handle data processing.

12. **Handle Backend Responses**:

- Implement error handling and data processing logic in your Angular components to handle
backend responses appropriately.

By following these steps, you can effectively integrate a backend into your Angular application,
enabling it to interact with a server-side environment for data management and processing.
Remember to follow best practices for security, performance, and maintainability throughout the
development process.