email-queue-microservice

📬 Go Email Queue Microservice

A lightweight Go microservice that accepts email jobs over HTTP, queues them, and processes them asynchronously using a concurrent worker pool.

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🚀 Features

• ✅ HTTP API to enqueue email jobs
• ✅ In-memory job queue with channels
• ✅ Multiple concurrent workers
• ✅ Simulated email delivery
• ✅ Graceful shutdown on SIGINT/SIGTERM
• ✅ Retry failed jobs (up to 3 times)
• ✅ Dead Letter Queue (DLQ) for permanently failed jobs

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📦 Folder Structure

emailservice/ ├── main.go # Entry point ├── api/ │ └── handler.go # HTTP handlers ├── queue/ │ ├── config.go # Queue config │ ├── interface.go # Job interface │ ├── job.go # Job model │ └── queue.go # Queue logic

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⚙️ Configuration

Configuration is currently hardcoded in main.go:

cfg := queue.Config{
    QueueSize:   10,
    WorkerCount: 3,
}

## How to Run
go run main.go

## 📬 API Endpoints

### 1. `POST /send-email`

Enqueue a new email job.

#### 📝 Request Payload

```json
{
  "to": "[email protected]",
  "subject": "Welcome!",
  "body": "Thanks for signing up."
}

curl -X POST http://localhost:8080/send-email \
  -H "Content-Type: application/json" \
  -d '{
    "to": "[email protected]",
    "subject": "Welcome!",
    "body": "Thanks for signing up."
}'