How/where do I save Published Events?

Getting Started
21

BTW, when looking at the docs again, the sample code for name request is using a PUBLIC event, not PRIVATE

    Particle.subscribe("spark/", handler);
    Particle.publish("spark/device/name");
22

Yeah, I looked at that as well the first time you mentioned it. I took it out of the code and tested again, but it didnt seem to fix the issue.

23

Now I see you do the subscribe five times here

void setup() {
	Serial.begin(9600);
	for(int i=0;i<5;i++) {
          Serial.println("waiting... " + String(5 - i));
          delay(1000);
          Particle.subscribe("spark/", handler); // <-- ????????????
	}
}

I'd rather do this

char myName[64];
void handler(const char *topic, const char *data) {
    strncpy(myName, data, sizeof(myName)-1); // save data in global var
    Serial.println("received " + String(topic) + ": " + String(data));
}

void setup() {
    Serial.begin(9600);
    Particle.subscribe("spark/", handler);

    Particle.connect();
    waitUntil(Particle.connected);
    Particle.publish("spark/device/name");
}

and put the original publish back in its place.

24

Now it just works as before - events get published but without info on the Sensor name. Which makes sense I suppose because publishing the name only appears in void setup() now?

ideally, the code could even be something like Particle.publish(eventName, ā€œspark/device/nameā€);
as I donā€™t really need frequent updates on battery status. Just having the sensor ping to me that it was picked up, and relaying its own name, already is sufficient.

25

You havenā€™t read the docs carefully enough, it seems :wink:

The Particle.publish("spark/device/name"); only publishes an event to the Particle cloud to request the name of the device and as a response the cloud sends an event containing the name to your device.
Your Particle.subscribe() just catches that event and stores the name - which my code does in myName.

What you do with that name in your code is entirely up to you - currently itā€™s not used, it just hangs around in the deviceā€™s RAM.

So try changing your publish to

  Particle.publish(eventName, myName, PRIVATE);
26

You sir, are the best. Hat off to you! :smiley:

As I was reading your post, I realized I indeed misread ā€˜ā€˜gives you device nameā€™ā€™ as ā€˜ā€˜sends device name as outputā€™ā€™. But you explained this very well to me; everything is working great now. The battery update is not so important to me so it doesnā€™t matter that itā€™s left out; my sensor is asleep 99.9% of the time so these batteries should last a really long time anyway.

Either way, thanks a lot for all your help, I really really appreciate it! :slight_smile:

1 Like
27

But you can have both anyway, just do this

      char data[96];
      float stateOfCharge = batteryMonitor.getSoC();
      snprintf(data, sizeof(data), "%s: %.2f", myName, stateOfCharge);

      Particle.publish(eventName, data, PRIVATE);

BTW, you can remove the 5sec wait loop from setup() too. It's not needed for the name retrieval.