Downtime Tracker

A simple and scalable website monitoring service built with Go. It periodically checks if your websites are up and sends email alerts when they go down or recover.

Features

• 🔍 Website Monitoring - Checks HTTPS websites every 10 minutes
• 📧 Email Alerts - Sends notifications when sites go down or recover
• 🔐 Email Verification - Users must verify their email before monitoring starts
• ⚡ Smart Alerts - Only sends emails when status changes (no spam!)
• 🚀 Concurrent Checks - Configurable worker pool for parallel checking
• 💾 Status Tracking - Redis-based status memory to prevent duplicate alerts

Tech Stack

• Go - Backend API and monitoring service
• Gin - HTTP web framework
• MongoDB - User and website storage
• Redis - Status tracking and token storage
• SMTP - Email delivery

Quick Start

Prerequisites

• Go 1.21+
• MongoDB
• Redis
• SMTP server (e.g., smtp2go, SendGrid)

Installation

git https://github.com/CodemHax/downtimetracker
cd downtimetracker
go mod download

Configuration

Create a .env file:

MONGODB_URI=mongodb://localhost:27017
REDIS_HOST=127.0.0.1
REDIS_PORT=6379
REDIS_PASSWORD=
REDIS_DB=0
SMTP_HOST=mail.smtp2go.com
SMTP_PORT=2525
SMTP_USER=your-username
SMTP_PASS=your-password
SMTP_FROM=noreply@yourdomain.com
LINK=http://localhost:8080
CHECKER_TIMEOUT=5000
CHECKER_CONCURRENCY=5

Run

go run .

Server starts at http://localhost:8080

API Endpoints

Health Check

GET /ping

Response: {"message": "pong"}

Add Website to Monitor

POST /add
Content-Type: application/json

{
    "email": "user@example.com",
    "website": "https://yoursite.com"
}

Verify Email

GET /verify?email=user@example.com&token=YOUR_TOKEN

API Documentation (Swagger)

After starting the server, access the Swagger UI at:

http://localhost:8000/swagger/index.html

To update the docs after changing endpoints or comments, run:

swag init

Project Structure

downtimetracker/
├── main.go                 # Entry point
├── cmd/
│   └── api.go              # API handlers
├── internals/
│   ├── database/
│   │   ├── mongo/          # MongoDB client
│   │   └── redis/          # Redis client
│   ├── mail/               # SMTP email sender
│   ├── models/             # Data models
│   └── utlis/              # Checker utilities
├── .env                    # Configuration
├── .gitignore
└── README.md

How It Works

1. User adds a website via /add endpoint
2. Verification email is sent to the user
3. User clicks the verification link
4. Service starts monitoring the website every 10 minutes
5. If site goes down → Email alert sent
6. If site recovers → Recovery email sent
7. No repeated emails while status unchanged

License

MIT