httpSMS

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httpSMS is a service that lets you use your Android phone as an SMS Gateway to send and receive SMS messages. You make a request to a simple HTTP API and it triggers your Android phone to send an SMS. SMS messages received on your android phone can also be forwarded to your webhook endpoint.

Quick Start Guide: https://docs.httpsms.com

• Why?
• Web UI
• API
• Android App
• Chat/forum
• Features
  • End-to-end Encryption
  • Webhook
  • Back Pressure
  • Message Expiration
• API Clients
• Flows
  • Sending an SMS Message
• Self Host Setup - Docker
• Integration Testing
• License

I'm originally from Cameroon and I wanted an automated way to send and receive SMS messages using an API. Unfortunately many countries don't support the ability to buy virtual phone numbers, and I could not find a good ready-made solution that could help me send/receive SMS messages using a mobile phone using an intuitive http API.

The web interface https://httpsms.com is built using Nuxt and Vuetify. It is hosted as a single page application on firebase. The source code is in the web directory

The API https://api.httpsms.com is built using Fiber, Go and CockroachDB for the database. It runs as a serverless application on Google Cloud Run. The API documentation can be found here https://api.httpsms.com/index.html

// Sending an SMS Message using Go
client := htpsms.New(htpsms.WithAPIKey(/* API Key from https://httpsms.com/settings */))

client.Messages.Send(context.Background(), &httpsms.MessageSendParams{
    Content: "This is a sample text message",
    From:    "+18005550199",
    To:      "+18005550100",
})

The Android App is a native application built using Kotlin with material design principles. This app must be installed on an Android phone before you can start sending and receiving SMS messages.

There are a few ways to get in touch with me and/or the rest of the community. Feel free to use any of these methods. Whatever works best for you:

• Discord server - direct chat with the community
• GitHub issues - questions, features, bugs

You can encrypt your messages end-to-end using the military grade AES-256 encryption algorithm. Your encryption key is stored only on our mobile phone so the even the server won't have any way to view the content of your SMS messages which are sent and received on your Android phone.

If you want to build advanced integrations, we support webhooks. The httpSMS platform can forward SMS messages received on the android phone to your server using a callback URL which you provide.

In-order not to abuse the SMS API on android, you can set a rate limit e.g 3 messages per minute. Such that even if you call the API to send messages to 100 people, It will only send the messages at a rate of 3 messages per minute.

Sometimes it happens that the phone doesn't get the push notification in time and I can't send the SMS message. It is possible to set a timeout for which a message is valid and if a message becomes expired after the timeout elapses, you will be notified.

• Go: https://github.com/NdoleStudio/httpsms-go
• JavaScript/TypeScript: https://github.com/NdoleStudio/httpsms-node

sequenceDiagram
User->>+httpSMS API: Call /v1/messages/send API
httpSMS API-->>+Push Queue: Schedule notification about new message
httpSMS API-->>-User: Respond with 202 (Accepted)
Push Queue-->>+httpSMS API: [Async] Send notification request
httpSMS API-->>-Android App: Send push notification about new message
Android App-->>httpSMS API: [Async] Fetch message
Android App-->>Android App: Send Message using Android SMS API
Android App-->>httpSMS API: [Async] Send result of sending SMS
Android App-->>httpSMS API: [Async] Send Delivery Report

The application is distributed as Docker images and can be run on any host with Docker Engine or deployed to platforms such as Coolify, Portainer, CapRover, and Docker Swarm.

The full self-hosting documentation is organized in the docs/ directory:

git clone https://github.com/NdoleStudio/httpsms.git
cd httpsms
cp .env.example .env
# Edit .env with your Firebase, SMTP, and Cloudflare Turnstile credentials
docker compose up --build

The API runs database migrations automatically on first boot. The internal system user required by the event queue is also created automatically on first boot. Check the api service logs for the generated credentials if EVENTS_QUEUE_USER_ID and EVENTS_QUEUE_USER_API_KEY were not set before starting.

When the stack is running:

• Web UI: http://localhost:3000
• API: http://localhost:8000
• Swagger UI: http://localhost:8000/index.html

For detailed setup instructions including Firebase configuration, SMTP setup, and Android app build steps, refer to docs/self-hosting.md.

The project includes end-to-end integration tests that validate the complete SMS send/receive lifecycle. Tests run the full stack (API, PostgreSQL, Redis) in Docker alongside a phone emulator that simulates an Android device.

Full documentation: tests/README.md

Quick run:

cd tests
bash generate-firebase-credentials.sh
export FIREBASE_CREDENTIALS=$(jq -c . firebase-credentials.json)
docker compose up -d --build --wait
docker compose wait seed && sleep 2
go test -v -timeout 120s ./...
docker compose down -v

Integration tests also run automatically in CI on every push/PR to main.

This project is licensed under the GNU AFFERO GENERAL PUBLIC LICENSE Version 3 - see the LICENSE file for details