MQTT Topics

All MQTT topics in Sensorclouds follow a consistent hierarchical pattern.

Topic Pattern

tenant/{tenantId}/app/{applicationId}/device/{deviceToken}/{type}

tenant/{tenantId}/app/{applicationId}/device/{deviceToken}/data

Device → PlatformSend sensor readings to the platform

Payload formats:

JSON: {"temperature": 25.3, "humidity": 60}
Hex string: "48656C6C6F" — auto-detected and converted to bytes before decoding
Raw bytes: Processed by the device profile's payload decoder

tenant/{tenantId}/app/{applicationId}/device/{deviceToken}/cmd

Platform → DeviceReceive commands from the platform

Command payload format:

{
  "commandId": "uuid",
  "command": "reboot",
  "parameters": { "delay": 5 }
}

tenant/{tenantId}/app/{applicationId}/device/{deviceToken}/ack

Device → PlatformAcknowledge received commands

ACK payload format:

{
  "commandId": "uuid",
  "status": "success",
  "message": "Command executed"
}

tenant/{tenantId}/app/{applicationId}/device/{deviceToken}/status

Device → PlatformOnline/offline status via LWT

Status payload: {"status": "online"} or {"status": "offline"}

Devices can only access their own topics. The ACL service enforces:

Action	Allowed Topics
Publish	`/data`, `/ack`, `/status`
Subscribe	`/cmd`

Cross-device topic access is blocked. A device cannot publish to or subscribe to another device's topics.