14 KiB
SMS Gateway API
A Ruby on Rails REST API and WebSocket server for managing SMS messaging through Android gateway devices. This system allows you to send and receive SMS messages programmatically, manage OTP codes, and integrate SMS capabilities into your applications.
Features
- Gateway Management: Register and manage multiple Android SMS gateway devices
- Inbound SMS: Receive and process incoming SMS messages
- Outbound SMS: Send SMS messages through connected gateway devices
- OTP Management: Generate, send, and verify one-time passwords
- WebSocket Communication: Real-time bidirectional communication with gateway devices
- Webhook Support: Trigger webhooks for SMS events
- Rate Limiting: Protect API endpoints from abuse
- Load Balancing: Automatically distribute messages across multiple gateways
- Auto Failover: Retry failed messages and handle gateway offline scenarios
Tech Stack
- Ruby: 3.4.7
- Rails: 8.0.3
- Database: PostgreSQL 14+
- Cache/Queue: Redis 7+
- Background Jobs: Sidekiq 7
- WebSocket: Action Cable (Redis adapter)
- API Authentication: JWT + API Keys
Prerequisites
- Ruby 3.4.7
- PostgreSQL 14+
- Redis 7+
- Bundler 2.x
Installation
1. Clone the repository
git clone <repository-url>
cd MySMSAPio
2. Install dependencies
bundle install
3. Set up environment variables
Create a .env file in the root directory:
# Database
DATABASE_URL=postgresql://localhost/my_smsa_pio_development
# Redis
REDIS_URL=redis://localhost:6379/1
# CORS
ALLOWED_ORIGINS=*
# Phone validation
DEFAULT_COUNTRY_CODE=US
# Rails
SECRET_KEY_BASE=your_secret_key_here
RAILS_ENV=development
4. Create and set up the database
bin/rails db:create
bin/rails db:migrate
bin/rails db:seed
Important: Save the API keys displayed after seeding! They won't be shown again.
5. Start Redis (if not running)
redis-server
6. Start Sidekiq (background jobs)
bundle exec sidekiq
7. Start the Rails server
bin/rails server
The API will be available at http://localhost:3000
API Documentation
Base URL
Development: http://localhost:3000
Production: https://your-domain.com
Authentication
All API endpoints (except gateway registration) require an API key in the Authorization header:
Authorization: Bearer your_api_key_here
There are two types of API keys:
- Gateway Keys: Start with
gw_live_- used by Android gateway devices - Client Keys: Start with
api_live_- used by your applications
Gateway Device APIs
Register a New Gateway
Register an Android device as an SMS gateway.
Endpoint: POST /api/v1/gateway/register
Request:
{
"device_id": "unique-device-identifier",
"name": "My Gateway Phone"
}
Response (201 Created):
{
"success": true,
"api_key": "gw_live_abc123...",
"device_id": "unique-device-identifier",
"websocket_url": "ws://localhost:3000/cable"
}
⚠️ Important: Save the api_key immediately. It will only be shown once!
Send Heartbeat
Keep the gateway connection alive and update status.
Endpoint: POST /api/v1/gateway/heartbeat
Headers: Authorization: Bearer gw_live_...
Request:
{
"status": "online",
"messages_in_queue": 5,
"battery_level": 85,
"signal_strength": 4
}
Response (200 OK):
{
"success": true,
"pending_messages": 2
}
Report Received SMS
Submit an SMS message received by the gateway device.
Endpoint: POST /api/v1/gateway/sms/received
Headers: Authorization: Bearer gw_live_...
Request:
{
"sender": "+1234567890",
"message": "Hello, this is a test message",
"timestamp": "2025-10-19T10:30:00Z"
}
Response (200 OK):
{
"success": true,
"message_id": "msg_abc123..."
}
Report SMS Delivery Status
Update the delivery status of an outbound SMS.
Endpoint: POST /api/v1/gateway/sms/status
Headers: Authorization: Bearer gw_live_...
Request:
{
"message_id": "msg_abc123",
"status": "delivered",
"error_message": null
}
Status values: delivered, failed, sent
Response (200 OK):
{
"success": true
}
Client Application APIs
Send SMS
Send an SMS message through the gateway.
Endpoint: POST /api/v1/sms/send
Headers: Authorization: Bearer api_live_...
Request:
{
"to": "+1234567890",
"message": "Your verification code is: 123456"
}
Response (202 Accepted):
{
"success": true,
"message_id": "msg_xyz789",
"status": "queued"
}
Check SMS Status
Check the delivery status of a sent message.
Endpoint: GET /api/v1/sms/status/:message_id
Headers: Authorization: Bearer api_live_...
Response (200 OK):
{
"message_id": "msg_xyz789",
"status": "delivered",
"sent_at": "2025-10-19T10:30:00Z",
"delivered_at": "2025-10-19T10:30:05Z",
"failed_at": null,
"error_message": null
}
Get Received SMS
Retrieve inbound SMS messages.
Endpoint: GET /api/v1/sms/received
Headers: Authorization: Bearer api_live_...
Query Parameters:
phone_number(optional): Filter by phone numbersince(optional): ISO 8601 timestamp to filter messages after this timelimit(optional): Number of messages per page (default: 50, max: 100)
Response (200 OK):
{
"messages": [
{
"message_id": "msg_abc",
"from": "+1234567890",
"message": "Reply message content",
"received_at": "2025-10-19T10:30:00Z"
}
],
"total": 25,
"page": 1,
"pages": 1
}
OTP APIs
Send OTP
Generate and send a one-time password.
Endpoint: POST /api/v1/otp/send
Headers: Authorization: Bearer api_live_...
Request:
{
"phone_number": "+1234567890",
"purpose": "authentication",
"expiry_minutes": 5
}
Response (200 OK):
{
"success": true,
"expires_at": "2025-10-19T10:35:00Z",
"message_id": "msg_otp123"
}
Rate Limits: Maximum 3 OTP codes per phone number per hour.
Verify OTP
Verify an OTP code.
Endpoint: POST /api/v1/otp/verify
Headers: Authorization: Bearer api_live_...
Request:
{
"phone_number": "+1234567890",
"code": "123456"
}
Response (200 OK) - Success:
{
"success": true,
"verified": true
}
Response (200 OK) - Failed:
{
"success": false,
"verified": false,
"error": "Invalid or expired OTP",
"attempts_remaining": 2
}
Admin APIs
List Gateways
Get all registered gateway devices.
Endpoint: GET /api/v1/admin/gateways
Headers: Authorization: Bearer api_live_...
Response (200 OK):
{
"gateways": [
{
"id": 1,
"device_id": "test-gateway-001",
"name": "Test Gateway 1",
"status": "online",
"last_heartbeat_at": "2025-10-19T10:30:00Z",
"messages_sent_today": 145,
"messages_received_today": 23,
"total_messages_sent": 1543,
"total_messages_received": 892,
"active": true,
"priority": 1,
"metadata": {},
"created_at": "2025-10-19T08:00:00Z"
}
]
}
Toggle Gateway Status
Enable or disable a gateway.
Endpoint: POST /api/v1/admin/gateways/:id/toggle
Headers: Authorization: Bearer api_live_...
Response (200 OK):
{
"success": true,
"gateway": {
"id": 1,
"device_id": "test-gateway-001",
"active": false
}
}
Get System Statistics
Get overall system statistics.
Endpoint: GET /api/v1/admin/stats
Headers: Authorization: Bearer api_live_...
Response (200 OK):
{
"gateways": {
"total": 2,
"active": 2,
"online": 1,
"offline": 1
},
"messages": {
"total_sent": 5432,
"total_received": 892,
"sent_today": 168,
"received_today": 23,
"total_today": 191,
"pending": 3,
"failed_today": 2
},
"otp": {
"sent_today": 45,
"verified_today": 42,
"verification_rate": 93.33
},
"timestamp": "2025-10-19T10:30:00Z"
}
WebSocket Connection (Gateway Devices)
Gateway devices connect via WebSocket for real-time bidirectional communication.
Connection URL
ws://localhost:3000/cable?api_key=gw_live_your_key_here
Subscribe to Gateway Channel
{
"command": "subscribe",
"identifier": "{\"channel\":\"GatewayChannel\",\"api_key_digest\":\"sha256_hash_of_api_key\"}"
}
Messages from Server
Send SMS Command:
{
"action": "send_sms",
"message_id": "msg_123",
"recipient": "+1234567890",
"message": "Your OTP is: 123456"
}
Messages to Server
Heartbeat:
{
"action": "heartbeat",
"battery_level": 85,
"signal_strength": 4,
"messages_in_queue": 0
}
Delivery Report:
{
"action": "delivery_report",
"message_id": "msg_123",
"status": "delivered"
}
Message Received:
{
"action": "message_received",
"sender": "+1234567890",
"message": "Hello",
"timestamp": "2025-10-19T10:30:00Z"
}
Background Jobs
The system uses Sidekiq for background processing:
Scheduled Jobs
- CheckGatewayHealthJob: Runs every minute to mark offline gateways
- CleanupExpiredOtpsJob: Runs every 15 minutes to delete expired OTP codes
- ResetDailyCountersJob: Runs daily at midnight to reset message counters
Processing Jobs
- SendSmsJob: Handles outbound SMS delivery
- ProcessInboundSmsJob: Processes received SMS and triggers webhooks
- RetryFailedSmsJob: Retries failed messages with exponential backoff
- TriggerWebhookJob: Executes webhook HTTP calls
Webhooks
Configure webhooks to receive real-time notifications for SMS events.
Webhook Events
sms_received: Triggered when an inbound SMS is receivedsms_sent: Triggered when an outbound SMS is sentsms_failed: Triggered when an SMS fails to send
Webhook Payload Example
{
"event": "sms_received",
"message_id": "msg_xyz",
"from": "+1234567890",
"message": "Hello",
"received_at": "2025-10-19T10:30:00Z",
"gateway_id": "test-gateway-001"
}
Webhook Signature
If a secret_key is configured, webhooks include an HMAC-SHA256 signature in the X-Webhook-Signature header for verification.
Error Responses
All errors follow this format:
{
"error": "Error message here"
}
Common HTTP status codes:
400 Bad Request: Invalid request parameters401 Unauthorized: Missing or invalid API key403 Forbidden: Insufficient permissions404 Not Found: Resource not found422 Unprocessable Entity: Validation errors429 Too Many Requests: Rate limit exceeded500 Internal Server Error: Server error
Development
Running Tests
bin/rails test
Code Quality
Check code style:
bin/rubocop
Security scan:
bin/brakeman
Console Access
bin/rails console
Database Console
bin/rails dbconsole
Deployment
Using Kamal
This project is configured for deployment with Kamal.
# Deploy to production
bin/kamal deploy
# View logs
bin/kamal logs
# Access console
bin/kamal console
Environment Variables (Production)
Required environment variables:
DATABASE_URL=postgresql://user:pass@host/database
REDIS_URL=redis://host:6379/1
SECRET_KEY_BASE=your_production_secret
RAILS_ENV=production
ALLOWED_ORIGINS=https://yourdomain.com
DEFAULT_COUNTRY_CODE=US
Monitoring
Health Check
GET /up
Returns 200 if the application is healthy.
Sidekiq Web UI
Mount Sidekiq web interface in config/routes.rb (protect with authentication in production):
require 'sidekiq/web'
mount Sidekiq::Web => '/sidekiq'
Architecture
┌─────────────────┐ ┌──────────────────┐
│ │ │ │
│ Android SMS │◄───WS──►│ Rails API │
│ Gateway App │ │ Action Cable │
│ │ │ │
└─────────────────┘ └────────┬─────────┘
│
┌────────┴─────────┐
│ │
┌───────────────────┤ PostgreSQL │
│ │ (Messages, OTP) │
│ │ │
│ └──────────────────┘
│
│ ┌──────────────────┐
│ │ │
└──────────────────►│ Redis │
│ (Cache, Jobs, │
│ WebSockets) │
│ │
└────────┬─────────┘
│
┌────────┴─────────┐
│ │
│ Sidekiq │
│ (Background │
│ Jobs) │
│ │
└──────────────────┘
License
MIT License
Support
For issues and questions, please create an issue on GitHub.