homelab-optimized/docs/services/individual/signal-cli-rest-api.md

# Signal Cli Rest Api

**🟢 Communication Service**

## 📋 Service Overview

| Property | Value |
|----------|-------|
| **Service Name** | signal-cli-rest-api |
| **Host** | homelab_vm |
| **Category** | Communication |
| **Difficulty** | 🟢 |
| **Docker Image** | `bbernhard/signal-cli-rest-api` |
| **Compose File** | `hosts/vms/homelab-vm/signal_api.yaml` |
| **Directory** | `hosts/vms/homelab-vm` |
| **API Version** | 0.98 |
| **Mode** | `native` |
| **Registered Number** | `REDACTED_PHONE_NUMBER` |

## 🎯 Purpose

Provides a REST API wrapper around `signal-cli`, enabling other homelab services to send and receive Signal messages programmatically. Used for alerting and notifications.

## 🚀 Quick Start

### Prerequisites
- Docker and Docker Compose installed
- Basic understanding of REDACTED_APP_PASSWORD
- Access to the host system (homelab_vm)

### Deployment
```bash
# Navigate to service directory
cd homelab_vm

# Start the service
docker-compose up -d

# Check service status
docker-compose ps

# View logs
docker-compose logs -f signal-cli-rest-api
```

## 🔧 Configuration

### Docker Compose Configuration
```yaml
# signal-api (main REST API)
container_name: signal-api
image: bbernhard/signal-cli-rest-api
environment:
  - MODE=native
ports:
  - 8080:8080
restart: always
volumes:
  - /home/homelab/docker/signal:/home/.local/share/signal-cli

# signal-bridge (Python bridge, port 5000)
# Separate container — Python 3.11
container_name: signal-bridge
ports:
  - 5000:5000
restart: always
```

### Environment Variables
| Variable | Value | Description |
|----------|-------|-------------|
| `MODE` | `native` | Configuration variable |


### Port Mappings
| Host Port | Container Port | Protocol | Purpose |
|-----------|----------------|----------|----------|
| 8080 | 8080 | TCP | Alternative HTTP port |


### Volume Mappings
| Host Path | Container Path | Type | Purpose |
|-----------|----------------|------|----------|
| `/home/homelab/docker/signal` | `/home/.local/share/signal-cli` | bind | Data storage |


## 🌐 Access Information

### Web Interface
- **API**: `http://homelab.tail.vish.gg:8080` (Tailscale only)
- **Swagger UI**: `http://homelab.tail.vish.gg:8080/v1/api-docs/`
- **Bridge**: `http://homelab.tail.vish.gg:5000`

### Registered Account
- **Phone number**: `REDACTED_PHONE_NUMBER`
- No API key required — unauthenticated REST API

## Arr Suite Integration

Signal notifications are configured in Lidarr, Sonarr, Radarr, Prowlarr, and Whisparr on Atlantis.

### Important: Use LAN IP, not Tailscale IP

Signal-api runs on **homelab-vm** (`192.168.0.210:8080`). All Atlantis arr services use the **LAN IP** to reach it.

**Why not the Tailscale IP?** Synology NAS devices (Atlantis, Calypso) run Tailscale in userspace networking mode — there is no `tailscale0` tun device, so the kernel cannot route TCP traffic to Tailscale IPs. While `tailscale configure-host` can enable kernel networking temporarily, it is unstable on Synology and causes tailscaled to crash repeatedly. The LAN path is reliable since both hosts are on the same 192.168.0.0/24 network.

| Setting | Value |
|---------|-------|
| **Host** | `192.168.0.210` |
| **Port** | `8080` |
| **Use SSL** | No |
| **Sender Number** | `REDACTED_PHONE_NUMBER` |
| **Receiver** | `REDACTED_PHONE_NUMBER` |

### Configured Apps (Atlantis)

| App | Port | Notification ID |
|-----|------|----------------|
| Lidarr | 8686 | 3 |
| Sonarr | 8989 | 2 |
| Radarr | 7878 | 1 |
| Prowlarr | 9696 | 1 |
| Whisparr | 6969 | 1 |
| Bazarr | 6767 | N/A (SQLite) |

### Updating the host via API (Lidarr/Sonarr/Radarr/Prowlarr/Whisparr)

If the host needs updating (e.g. after an IP change), use the arr API:

```bash
# Get current notification config
curl -s -H "X-Api-Key: <APIKEY>" http://100.83.230.112:<PORT>/api/v3/notification/<ID>

# Test notification
curl -s -X POST -H "X-Api-Key: <APIKEY>" http://100.83.230.112:<PORT>/api/v3/notification/test/<ID>
```

### Updating the host for Bazarr (SQLite direct edit)

Bazarr stores notifier config in its SQLite DB. The REST API does **not** persist notification changes — you must edit the DB directly.

```bash
# 1. Copy DB out of container (via Portainer archive API or docker cp on Atlantis)
docker cp bazarr:/config/db/bazarr.db /tmp/bazarr.db

# 2. Update the Signal API URL
python3 -c "
import sqlite3
conn = sqlite3.connect('/tmp/bazarr.db')
cur = conn.cursor()
cur.execute(\"UPDATE table_settings_notifier SET url='signal://192.168.0.210:8080/%2B15103961064/%2B15103961064' WHERE name='Signal API'\")
conn.commit()
conn.close()
"

# 3. Stop Bazarr, copy DB back, restart
docker stop bazarr
docker cp /tmp/bazarr.db bazarr:/config/db/bazarr.db
docker restart bazarr
```

## 🔒 Security Considerations

- ⚠️ Consider adding security options (no-new-privileges)
- ⚠️ Consider running as non-root user

## 📊 Resource Requirements

No resource limits configured

### Recommended Resources
- **Minimum RAM**: 512MB
- **Recommended RAM**: 1GB+
- **CPU**: 1 core minimum
- **Storage**: Varies by usage

### Resource Monitoring
Monitor resource usage with:
```bash
docker stats
```

## 🔍 Health Monitoring

### Manual Health Checks
```bash
# Check container status (run on homelab VM)
ssh homelab  # password: "REDACTED_PASSWORD"
docker ps --filter name=signal

# Check API health endpoint
curl -s http://localhost:8080/v1/health
# Expected: {"status":"alive"}

# Check API version and registered accounts
curl -s http://localhost:8080/v1/about
# Returns: {"mode":"native","version":"0.97","build_nr":...}

# List registered accounts
curl -s http://localhost:8080/v1/accounts
# Should return: ["REDACTED_PHONE_NUMBER"]

# Send a test message
curl -s -X POST http://localhost:8080/v2/send \
  -H 'Content-Type: application/json' \
  -d '{"message":"test","number":"REDACTED_PHONE_NUMBER","recipients":["+1XXXXXXXXXX"]}'
```

### Container Names
| Container | Purpose | Port |
|-----------|---------|------|
| `signal-api` | REST API wrapper for signal-cli | 8080 |
| `signal-bridge` | Python 3.11 bridge | 5000 |

## 🚨 Troubleshooting

### Common Issues
**Service won't start**
- Check Docker logs: `docker-compose logs service-name`
- Verify port availability: `netstat -tulpn | grep PORT`
- Check file permissions on mounted volumes

**Can't access web interface**
- Verify service is running: `docker-compose ps`
- Check firewall settings
- Confirm correct port mapping

**Performance issues**
- Monitor resource usage: `docker stats`
- Check available disk space: `df -h`
- Review service logs for errors

### Useful Commands
```bash
# Check service status
docker-compose ps

# View real-time logs
docker-compose logs -f signal-cli-rest-api

# Restart service
docker-compose restart signal-cli-rest-api

# Update service
docker-compose pull signal-cli-rest-api
docker-compose up -d signal-cli-rest-api

# Access service shell
docker-compose exec signal-cli-rest-api /bin/bash
# or
docker-compose exec signal-cli-rest-api /bin/sh
```

## 📚 Additional Resources

- **Official Documentation**: Check the official docs for signal-cli-rest-api
- **Docker Hub**: [bbernhard/signal-cli-rest-api](https://hub.docker.com/r/bbernhard/signal-cli-rest-api)
- **Community Forums**: Search for community discussions and solutions
- **GitHub Issues**: Check the project's GitHub for known issues

## 🔗 Related Services

Other services in the communication category on homelab_vm

---

*This documentation is auto-generated from the Docker Compose configuration. For the most up-to-date information, refer to the official documentation and the actual compose file.*

**Last Updated**: 2026-03-29 (Switched all arr-stack Signal notifications from Tailscale IP to LAN IP 192.168.0.210 — Synology userspace networking cannot route TCP to Tailscale IPs reliably)
**Configuration Source**: `hosts/vms/homelab-vm/signal_api.yaml`