Using MQTT to publish from Photon

[chucksterv]

I'm trying to publish to the mosquitto test server when there's a button press in the Photon. However, it only runs once even though there's a loop present.

if(buttonState == LOW)
{

    // if light is currently off, switch to on
    if(ledStatus == "off")
    {
        ledStatus = "on";
        
        if (client.isConnected())
        {
            
            digitalWrite(led7, HIGH);
            client.publish("doorOpen", "Door Opened");
            //client.publish("timeStamp", Time.timeStr());
        }
        delay(20000);
        digitalWrite(led, HIGH);
        digitalWrite(led7, LOW);
        delay(5000);
        ledStatus = "off";
        digitalWrite(led, LOW);


        
    }
    // else light must be on, so switch to off
    else 
    {

    }
}

// wait 0.2 seconds before checking button again
delay(200);
client.loop();

Not too sure what I'm doing wrong. I also noticed that it won't publish at all if the if(client.isConnected()) is located after the delay(20000);

[ScruffR]

You have 25+ seconds of delay in your loop() after the initial button press, so that doesn’t help responsiveness

It’s highly advisable to avoid delay() entirely.

Also when already checking for client.isConnected() it would make sense to do something in case that is not the case - i.e. reconnect.

We are also missing some context

• can ledStatus be changed anywhere else than in the code shown?
• if not, that “flag” is superfluous
• if yes, then whenever the current state is "on" no button press will have any effect until the state gets reset to "off" somewhere else
• what does the rest of your code do?

[chucksterv]

Would the delay be a reason to not publish at all?

I’ll add more functionality for the if client isn’t connected. Thanks !

As for the context, that is pretty much the main body of the code. I just skipped copying the setup and the initializing parts of the code. ledstatus is originally set as off. As for the project, it’s sort of a concept demo I’m working on for proper hand sanatization timer. So I can’t take the delays out. Or rather I need some method to create that 25 second gap.

[ScruffR]

@chucksterv

So I can’t take the delays out

You can, you just need to be clever about it
For simple time stuff like that you can use millis() as a base and measure the time between the last state to the next.
For more elaborate stuff FSM would be the paradigm to follow.

Alternatively you can use Software Timers.