Email Service

This project implements an email service using Go. The service supports asynchronous email sending with attachments, retries for failed deliveries, and integration with RabbitMQ for task queuing.

Features

• Asynchronous email processing: Ensures non-blocking API responses by processing emails in the background.
• Attachment support: Allows sending emails with file attachments encoded in base64 format.
• Retry mechanism: Automatically retries email delivery on failure, up to a configurable limit.
• RabbitMQ integration: Uses RabbitMQ for reliable task queuing and delivery.

Prerequisites

Before running the project, ensure you have the following installed:

• Docker
• Docker Compose

Getting Started

Setup

1. Clone the repository:

   git clone https://github.com/your-username/email-service.git
   cd email-service

2. Create an .env file in the root directory with the following content:

   SMTP_HOST=smtp.example.com
   SMTP_PORT=587
   SMTP_USER=[email protected]
   SMTP_PASSWORD=your-password
   RABBITMQ_URL=amqp://guest:guest@localhost:5672/
   DATABASE_URL=your-database-connection-string
   DB_HOST=your-database-host # eg: db or localhost
   DB_PORT=your-database-port # eg: 5432
   DB_USER=your-database-username # eg: postgres
   DB_NAME=your-database-name # eg: postgres
   DB_PASSWORD=your-database-password 
   SECRET_KEY=your-secret-key

3. Build and start the services using Docker Compose:

   docker-compose up --build

API Usage

The following API endpoint is available:

Send Email

Endpoint: POST /send-email

Request Body:

{
  "from": "[email protected]",
  "to": "[email protected]",
  "subject": "Test Email",
  "body": "This is a test email.",
  "attachments": [
    {
      "filename": "test.txt",
      "content_type": "text/plain",
      "data": "base64-encoded-content"
    }
  ],
  "cc": ["[email protected]"],
  "bcc": ["[email protected]"],
  "reply_to": "[email protected]"
}

Response:

• Success: HTTP 202 Accepted

  {
    "message": "Email task successfully enqueued",
    "data": null,
    "status_code":202
  }

• Failure: HTTP 400/500 with an error message

Project Structure

email-service/
├── cmd/            # App Entry Point
│   ├── api/        # API
│   ├── woker/      # Woker logic
├── internal/
│   ├── http/       # HTTP Handlers
│   ├── dto/        # Data Transfer Objects
│   ├── models/     # Database models
│   ├── services/   # Business logic
├── migrate/        # Migration function
├── utils/          # Utility functions
├── Dockerfile      # Docker build configuration
├── docker-compose.yml # Docker Compose configuration
└── README.md       # Project documentation

Running the Worker

The worker process listens for tasks from RabbitMQ and processes email sending tasks. The worker is automatically started when you run the docker-compose up command.

Docker Configuration

The project uses Docker for containerization. The docker-compose.yml file defines two services:

• api: The main API service
• worker: The background worker for processing email tasks

Build and Run

To start the application:

docker-compose up --build

To stop the application:

docker-compose down

Environment Variables

Variable	Description
SMTP_HOST	SMTP server host
SMTP_PORT	SMTP server port
SMTP_USER	SMTP username
SMTP_PASSWORD	SMTP password
RABBITMQ_URL	RabbitMQ connection URL
DATABASE_URL	Database connection string
DB_NAME	Database Name
DB_HOST	Database Host
DB_USER	Database User
DB_PORT	Database Port
DB_PASSWORD	Database password

License

This project is licensed under the Apache 2.0 License.