Functioning mqtt ingestion and db write, formating changes, device manager initiated

services/device_manager/README.md

@@ -1,3 +1,73 @@
-# Device Manager
+# Device Manager Service
 
-This is a service that has a key role in devices and their management. It is used to provision, create, manage the lifecycle of devices and everything connected to it.
+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
+```http
+POST /api/v1/devices/register
+Content-Type: application/json
+
+{
+  "name": "Living Room Sensor",
+  "location": "Living Room"
+}
+```
+
+**Response (201):**
+```json
+{
+  "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
+```http
+GET /api/v1/devices/{device_id}
+```
+
+**Response (200):**
+```json
+{
+  "device_id": "a1b2c3d4",
+  "name": "Living Room Sensor",
+  "location": "Living Room",
+  "is_active": true,
+  "created_at": "2025-01-15T10:30:00Z"
+}
+```
+
+### Revoke Device Certificate
+```http
+POST /api/v1/devices/{device_id}/revoke
+```
+
+**Response (200):**
+```json
+{
+  "device_id": "a1b2c3d4",
+  "revoked_at": "2025-06-15T10:30:00Z"
+}
+```