The Device Manager service handles device registration, certificate issuance, and lifecycle management for the IoT dashboard. It provides a REST API for device onboarding and integrates with the MQTT broker via mTLS authentication.

Architecture

The service provides:

Device Registration: REST API endpoint to register new devices
Certificate Management: Generates X.509 certificates signed by internal CA
Device Lifecycle: Tracks device status (active, revoked)
mTLS Integration: Certificates used for MQTT broker authentication

Technology Stack

FastAPI: REST API framework
SQLAlchemy: Database ORM
Cryptography: X.509 certificate generation
Nano ID: 8-character device identifiers
PostgreSQL: Device and certificate storage

API Endpoints

Register Device

POST /api/v1/devices/register
Content-Type: application/json

{
  "name": "Living Room Sensor",
  "location": "Living Room"
}

Response (201):

{
  "device_id": "a1b2c3d4",
  "name": "Living Room Sensor",
  "location": "Living Room",
  "certificate": "-----BEGIN CERTIFICATE-----\n...",
  "private_key": "-----BEGIN RSA PRIVATE KEY-----\n...",
  "ca_certificate": "-----BEGIN CERTIFICATE-----\n...",
  "expires_at": "2026-01-15T10:30:00Z"
}

Get Device

GET /api/v1/devices/{device_id}

Response (200):

{
  "device_id": "a1b2c3d4",
  "name": "Living Room Sensor",
  "location": "Living Room",
  "is_active": true,
  "created_at": "2025-01-15T10:30:00Z"
}

Revoke Device Certificate

POST /api/v1/devices/{device_id}/revoke

Response (200):

{
  "device_id": "a1b2c3d4",
  "revoked_at": "2025-06-15T10:30:00Z"
}