Auth Service

Auth Service is a microservice for user authentication using JWT tokens, PostgreSQL, and Memcached.

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Features

1. User Registration (POST /register): Registers a new user in the system.

2. Authentication and Token Generation (POST /login): Authenticates the user and returns a JWT token.

3. Token Validation (GET /validate-token): Validates the token using Memcached and the database as a fallback.

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Technologies

• Go: Programming language.
• PostgreSQL: Database for storing user information.
• Memcached: Caching layer for token validation.
• Goose: Database migration tool.
• Gin: Web framework for building REST APIs.

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Installation and Setup

Steps:

1. Clone the repository:

   git clone https://github.com/your-repo/auth-service.git
   cd auth-service

2. Ensure you have Go, Docker, and Docker Compose installed.

3. Start the services (PostgreSQL, Memcached, and the application):

   docker-compose up --build

4. Run database migrations:

   make migrate-up

5. The service will be available at:

   http://localhost:8080
   

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API Examples

Register a User

curl -X POST http://localhost:8080/register \
  -H "Content-Type: application/json" \
  -d '{
        "username": "testuser",
        "password": "testpassword"
      }'

Authenticate and Get a Token

curl -X POST http://localhost:8080/login \
  -H "Content-Type: application/json" \
  -d '{
        "username": "testuser",
        "password": "testpassword"
      }'

Validate a Token

curl -X GET http://localhost:8080/validate-token \
  -H "Authorization: Bearer <your JWT token>"

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Makefile Commands

• Build the application: make build
• Run the application: make run
• Format the code: make fmt
• Lint the code: make lint
• Run migrations: make migrate-up
• Rollback migrations: make migrate-down

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Environment Variables

The following environment variables can be used for configuration:

Variable	Description	Default
DATABASE_URL	PostgreSQL connection string	postgres://user:password@localhost:5432/auth_db?sslmode=disable
MEMCACHED_HOST	Memcached host	localhost
MEMCACHED_PORT	Memcached port	11211

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Directory Structure

auth-service/
├── cmd/
│   └── auth-service/      # Application entry point
├── internal/
│   ├── controller/        # API controllers
│   ├── model/             # Database models
│   ├── repository/        # Database access layer
│   └── service/           # Business logic
├── config/                # Configuration files
├── db/
│   └── migrations/        # Database migrations
├── Dockerfile             # Docker build configuration
├── docker-compose.yml     # Docker Compose configuration
├── Makefile               # Automation tasks
└── README.md              # Project documentation

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