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sensorsgatewaythingsboard

Thingsboard; Data about same sensor, but from a different (multiple) gateway

I have just started using Thingsboard and made some good progress in understanding how some of the basic stuff works ( mainly sending sensor data using mqtt ). But I have come to a complete halt at one point. Here is an explanation of the problem. Thingsboard version is 1.3.1

My setup:

  • 4x RPi (Raspberry Pi) used as gateways to gather data from bluetooth beacons
  • A set of bluetooth beacons

Here's what the system is supposed to do: Send periodic data from the gateways ( RPi ) to inform thingsboard that the gateway is alive The above part is working fine. I have set up the gateways to connect to thingsboard using access token, and post the data ( both the attributes and telemetry ). For sending attributes I use "v1/devices/me/attributes" and for telemetry data I use "v1/devices/me/telemetry", as mentioned in the documentation.

A typical string from the gateway indicating that it is alive is

{"gwA.macid": "00:00:00:00:00:00", "gwA.timestamp": "2018-02-16T19:20+01:00"}

The above part is working well. This is just for an indication that the gateway is well and able to communicate with the Thingsboard server. All the gateways connect to thingsboard using it's own respective access token and posts the above data.

Now the problem part ( or where I got halted )

The gateways gather the data about the nearby bluetooth beacons and post it too. The data format in which the gateways posts the beacon data is

{"bcn000001.mac": "00:00:00:00:00:00", "bcn000001.timeepoch": 1518939044}

The gateway ensures that each beacon data will have the correct prefix. For example

{"bcn000001.mac": "50:80:25:AA:BB:CC", "bcn000001.timeepoch": 1518939044}
{"bcn000002.mac": "50:80:25:RR:AA:DD", "bcn000002.timeepoch": 1518939039}
{"bcn000003.mac": "50:80:25:GG:33:EE", "bcn000003.timeepoch": 1518939020}

But the data about the same sensor can also come from another gateway. How do I show it on a single widget irrespective of which gateway the data comes from. If I choose "entity list" then either it does not work, or shows up all the 4 RPi gateways on the widget. This is not what I want. I have attached an image. I am not sure if I am able to explain this well but pls do let me know if there is any other information that I can furnish. I am adding an image to point to some things that I just mentioned. I have even separated the data out by using a prefix ( as mentioned in one of the earlier SO posts ). I have spent close to couple of days on this. This was not supposed to be difficult. At least that's what I thought when I got started.

enter image description here

Note: As I explore, I just learnt (realized) one more thing. I think this part was a little confusing so I thought I should inform others. When one adds a device in Thingsboard, there is an option to specify if the device "Is a Gateway". What it is trying to tell(ask?) is that whether thingsboard gateway service is installed on that device. In my case I made the mistake(?) of thinking that a device that gathers data from sensors and posts it to the server is a gateway device. I guess I'll try to install thingsboard gateway service on the raspberry pi, then see how it goes. I'll post an update once I am done but in the meantime any useful comments or suggestions - please keep em coming.

I have seen others ask very similar question on SO. Something fundamental like this shouldn't be so difficult. No point in have a hundred pages of documentation without a clear explanation of most basic steps towards setting up an IoT backend/dashboard. All I wanted to do is to display the same sensor data ( say Sensor A ) coming from "any one of the devices", to show on the same widget. If I choose single entity, the widget won't update if the data comes from other device. If I choose entity list, and turn on "Resolve as multiple entities", then I end up with the widget showing all the devices

enter image description here

Solution

  • you are using wrong API. The API you are looking for is gateway API which allows to push telemetry and other messages on behalf of other devices. Please use this API https://thingsboard.io/docs/reference/gateway-mqtt-api/ on the Raspberry Pi gateways. You can also use our Gateway project and modify it for your needs.