Smart home

Communication between components

Hub messages

Hub can produce several types of messages:

1. Hub start
2. Hub shutdown
3. Hub message
4. Heart beat
5. Device connected
6. Device disconnected
7. Device messages

Note that each message contains "hub-id" header !

Field "action" is a shortcut for the MessageAction

Hub start

This message must be sent firstly to identify hub.
Field "data" contains hub description and extra properties like heart beat period (hb)

    {
        "hub-id": "hub1",
        "action":"start",
        "data": "{\"description\":\"test-hub\", \"hb\":30}"
    }

Hub shutdown

Field "data" contains disconnection reason

    {
        "hub-id": "0b97d1b9-9759-4adc-b9a6-b885e1e9b872",
        "action":"shutdown",
        "data":"{\"reason\": \"shutting down\"}"
    }

Hub message

Reserved for the future ...
Notify about some changes in configuration or handle some user request and send response

    {
        "hub-id": "0b97d1b9-9759-4adc-b9a6-b885e1e9b872",
        "action":"hub-msg",
        "data": "important message"
    }

Hub heart beat

Hub must produce heart beat message with fixed period. For instance, each 30 seconds

    {
        "hub-id": "0b97d1b9-9759-4adc-b9a6-b885e1e9b872",
        "action":"alive",
        "data": "{\"ts\":1652919949,\"alive-devices\":5,\"total-devices\":10}"
    }

Device connected

Hub must send notification on device connection

• hub-id - const hub uuid
• device-id - const device uuid
• type - device type. Starts with "ACTUATOR__" or "SENSOR__"
• name - custom device name
• data - additional information can pe passed here as string (in json format)

    {
        "hub-id": "0b97d1b9-9759-4adc-b9a6-b885e1e9b872",
        "device-id":"ada9ff04-ed3f-470f-9c30-23068b9b8c02",
        "action": "device-connected",
        "data":"{\"unit\":\"celsius\",\"type\":\"SENSOR__thermometer\",\"name\":\"temperature imitator1\"}"
    }

Device disconnected

Hub must send notification on devices disconnection

• hub-id - const hub uuid
• device-id - const device uuid
• data - - disconnection reason

    {
        "hub-id": "0b97d1b9-9759-4adc-b9a6-b885e1e9b872",
        "device-id":"ada9ff04-ed3f-470f-9c30-23068b9b8c02",
        "action":"devices-disconnected",
        "data": "connection lost"
    }

Device message

• hub-id - const hub uuid
• device-id - const device uuid
• data - parsed information given from device and presented as a string in json format

    {
        "hub-id": "0b97d1b9-9759-4adc-b9a6-b885e1e9b872",
        "device-id":"ada9ff04-ed3f-470f-9c30-23068b9b8c02",
        "action":"msg",
        "data": "{\"value\": \"value\"}"
    }