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Moving forward to device-to-device and device-to-mobile communication in Ombori Grid we are introducing a new concept: spacesA space is a separate communication channel for deviceschannels

The idea behind channels is to process messages differently and isolate different client roles from each other (see examples below). Screen and IoT apps and modules can publish/subscribe to messages to/from any spacechannel.

Example, sending a message to the space channel names somespace somechannel in a screen app:

Code Block
export const App = () => {
  const pub = usePublish();

  const send = useCallback(() => {
    pub('somespacesomechannel/Some.MessageType', {payload: "goes here"});
  }, [pub]);
  ...
  return <button onClick={send} />
}

As you can see, to send a message to a spacespecific channel, just prefix it message type with the channels' name of the space and add slash.
Note that you can still send messages without prefix, they will be sent to the default space channel (which is internally called message) so you don't need to modify any existing code.

Subscribing to messages is done in similar fashion:

Code Block
export const App = () => {
  const [data, setData] = useState<any>(null);
  useSubscribe('somespacesomechannel/Another.MessageType', (payload) => {
    setData(payload);
  }, [setData])

  return <div>{data}</div>
} 

So, to subscribe to a message in somespace somechannel, just add a prefix to message type when calling useSubscribe

Same rules apply to modules/IoT apps. When communicating with the default spacechannel, don't use the prefix. When talking to a spacechannel, add space its name before an event type.

Usage

The idea behind spaces is messages are processed differently in different spaces:

  • message - this is default spacechannel, apps and modules on the same device can communicate with each other thru it. Messages do not leave the device. The channel is always available.

  • localnet - messages will be automatically send to any GridOS devices in the same local network. This requires messaging module. No internet connection required for this to operate.

  • remote - messages will be forwarded to a connected mobile remote app. Mobile remote app cannot write to the default spacechannel, it can only use remote. Requires messaging module, option must be enabled in module settings.

  • mobileapp - messages will be forwarded to a local mobile app. Local mobile app cannot write to the default spacechannel, it can only use mobileapp. Requires mobileapp module. No internet connection required for this to operate.

  • pubnub - messages are broadcasted between devices via pubnub service. Requires messaging module. PubKey and SubKey settings should be entered in module settings on each connected device.