MQTT to OpenHAB stalls after time

Setup, Configuration and Use Installation
21

I have two Shelly PM that somehow crashed my openhab.
They publish at 1s interval this topic:

{"id":0, "source":"init", "output":true, "apower":151.5, "voltage":222.5, "current":0.710, "aenergy":{"total":15764.484,"by_minute":[1936.493,2420.843,2402.431],"minute_ts":1652688287},"temperature":{"tC":62.1, "tF":143.8}}

label: Shelly Server PM
thingTypeUID: mqtt:topic
configuration: {}
bridgeUID: mqtt:broker:mosquittoDebianBroker
channels:
  - id: power
    channelTypeUID: mqtt:number
    label: Power
    description: null
    configuration:
      stateTopic: shellies/server-pm/status
      transformationPattern: JSONPATH:$.apower
  - id: powerSwitch
    channelTypeUID: mqtt:switch
    label: Power Switch
    description: null
    configuration:
      commandTopic: shellies/server-pm/rpc
      postCommand: false
      stateTopic: shellies/server-pm/status/switch:0
      transformationPattern: JS:shelly1plus.js
      off: '{"id":0, "src":"switch", "method":"Switch.Set",
        "params":{"id":0,"on":false}}'
      on: '{"id":0, "src":"switch", "method":"Switch.Set",
        "params":{"id":0,"on":true}}'
22

Can you share this script too?

And this topic is what the JSON extract is published to? With the colon?

23 
(function(i){
	var obj = JSON.parse(i);	
	var end = obj.output
		
	if (end == false){
		return "OFF";
	}	
	if (end == true){
		return "ON";
	}	
})(input)

yes

24

Thanks. I’ll try set something up tonight using the power data. I won’t copy the switch Channel, as I can’t quite tell what it’s doing, but I guess that’s not the one receiving all the updates?

25

the powerSwitch is not important it’s just to switch the power source on or off. And this topic does only update when there is a switch happening. The important one is the shellies/server-pm/status topic

26

So far everything is still up and running. I’m using the script below to publish data every 0.5 seconds.

import paho.mqtt.client as mqtt
import random
from time import sleep

#SETUP MQTT
mqtt_client = mqtt.Client("rate_test")
mqtt_client.connect("192.168.1.151")

run_time_hrs = 24
publish_interval = 0.5
steps = int(run_time_hrs*60*60/publish_interval)

for i in range(steps):
    apower = random.randrange(0, 300)
    message = '{"id":0, "source":"init", "output"
:true, "apower":'+str(apower)+', "voltage":222.5,
 "current":0.710, "aenergy":{"total":15764.484,"b
y_minute":[1936.493,2420.843,2402.431],"minute_ts
":1652688287},"temperature":{"tC":62.1, "tF":143.
8}}'

    print("{}/{}: Power: {}".format(i,steps,apowe
r))
    mqtt_client.publish("shellies/server-pm/statu
s",message)
    sleep(publish_interval)

mqtt_client.disconnect()

It’s been running for ~12hrs so far, and the openHAB Item is still updating.

EDIT:

Test Thing

Thing mqtt:topic:mqtt_rate_test "MQTT Rate Test" (mqtt:broker:MosquittoMqttBroker)  {
    Channels:
        Type number : power [
        	stateTopic="shellies/server-pm/status",
        	transformationPattern="JSONPATH:$.apower"
        ]
}

or

UID: mqtt:topic:mqtt_rate_test
label: MQTT Rate Test
thingTypeUID: mqtt:topic
configuration: {}
bridgeUID: mqtt:broker:MosquittoMqttBroker
channels:
  - id: power
    channelTypeUID: mqtt:number
    label: Number Value
    description: null
    configuration:
      retained: false
      postCommand: false
      step: 1
      formatBeforePublish: "%s"
      stateTopic: shellies/server-pm/status
      transformationPattern: JSONPATH:$.apower

Test Items

Number nMQTTRateTestPower "Power" {channel="mqtt:topic:mqtt_rate_test:power"}
DateTime dtMQTTRateTestPower "Last power" { channel="mqtt:topic:mqtt_rate_test:power" [profile="timestamp-update"] }
27

interesting mine failed after around 3 hours.
I will use your script and test if it won’t fail on my side as well

28

After 24hrs the Item is still actively updating, and the only thing that I can see which is different to ‘normal’ is increased Disk IO for the openHAB container:

image

(The first continuously high levels where during script testing, the second during this last period).

I have MapDB enabled with default config - perhaps the cause for this.

CPU usage was higher too during the testing periods, but only rising from 0.5% to 2%:

image

But the MQTT Binding didn’t seem to break a sweat.

29

ok I had running your script for more then 4 hours and no fail as well. I will now try to reproduce the mentioned error in the beginning of the thread with the Shelly PM device. lets see…