# device-control-service (Go)

Status: not implemented yet.

Responsibility:
- Expose a gRPC API (see `proto/device_control.proto`) for issuing commands
  to devices — called by Laravel (manual control) and rule-engine-service
  (rule-triggered actions).
- Publish the command to the device's MQTT topic (`devices/{device_id}/commands`)
  and listen for acknowledgements (`devices/{device_id}/ack`).
- Maintain the Device Shadow pattern in Redis: `desired_state` (what the user
  wants) vs `reported_state` (what the device confirmed), plus `status` and
  `last_seen`.
- Owns the health-check loop (or delegates to health-check-service): a ticker
  goroutine that flips a device to `offline` when `last_seen` exceeds a
  timeout, and emits an event for notification-service.

Not this service's job: deciding *when* to send a command based on sensor
thresholds — that's rule-engine-service's logic. This service only executes
and tracks state for whatever command it's given.