Server

The SafeCall server is a Bun-powered backend that provides the HTTP/WebSocket API, MQTT integration, real-time beacon tracking, and optional Zabbix bridge functionality.

Tech Stack

• Runtime: Bun
• Language: TypeScript
• Database: SQLite (via bun:sqlite)
• Auth: JWT with RS256 (via jose)
• MQTT: mqtt package for broker communication
• Validation: Valibot for schema validation
• Serialization: Protobuf (via protobufjs) for tracking logs

Entry Point

The server starts from server/src/server.ts. It reads main.config.json and initializes subsystems based on the server_features config:

"safecall" mode (full server)

1. Generate JWT RS256 key pair
2. Start SQLite databases (main + sensor)
3. Run pending migrations
4. Start HTTP + WebSocket server
5. Start MQTT client
6. Initialize beacon cache
7. Start tracking prediction
8. Start device sync

"bridge" mode (standalone)

1. Start MQTT client
2. Forward beacon/gateway data to Zabbix

Both modes can run simultaneously when server_features includes both "bridge" and "safecall".

Module Overview

Module	File	Purpose
HTTP Routes	src/routes/http.ts	All REST API endpoints
WebSocket	src/routes/ws.ts	Real-time subscriptions
MQTT	src/mqtt.ts	MQTT message dispatcher
Tracking	src/tracking.ts	Zone prediction algorithms
Events	src/events.ts	Panic buttons, SOS, sensor alerts
Cache	src/cache.ts	In-memory beacon state
Devices	src/devices.ts	Device sync to database
Bridge	src/bridge.ts	Zabbix/LLD integration
Guard	src/guard.ts	JWT auth middleware
Schemas	src/schemas.ts	Valibot schemas for DB rows

Data Flow

MQTT Broker
    │
    ▼
mqtt.ts (dispatcher)
    ├── bridge.ts → Zabbix
    ├── devices.ts → DB sync
    └── events.ts
            ├── cache.ts (beacon lookup)
            ├── tracking.ts (RSSI → zone prediction)
            └── KISS / ntfy.sh (notifications)

WebSocket Clients
    │
    ▼
ws.ts (subscribe by type)
    └── events.ts (test beacon simulation)

HTTP Clients
    │
    ▼
routes/http.ts
    └── guard.ts (JWT verification)

Key Dependencies

Package	Version	Purpose
jose	^6.0.10	JWT signing and verification
mqtt	^5.12.0	MQTT broker client
protobufjs	^7.5.4	Tracking log serialization
valibot	^1.1.0	Runtime schema validation

Development

cd server

# Install dependencies
bun install

# Run dev server with hot reload
bun run dev

# Type checking
bun run typecheck

# Run tests
bun test

# Run tests with watch
bun test --watch