Problem in reading data from Mqtt topic [ given new state is NULL]

Setup, Configuration and Use Scripts & Rules
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1

Hello,

I am currently facing issue while using MQTT binding. Currently i am publishing data from a python script using paho mqtt driver.

Using below code i am publishing data (i.e string) on topic “name” via python,
Python:
mqtt_client.publish("name",found_name)

From Serial Terminal when i use Mosquitto_sub -t name it shows me the data published on the topic. So i think python script is properly working.

Now in Openhab Configuration demo.item files i am reading data from the same topic:
Items file:

Number EPBM4_Tmp_eth "EPBM4 Temperature [%.2f °C]" { mqtt="<[mosquitto:name:state:default]" }

Now when in run openhab server it show me following error:

[ab.core.events.EventPublisherDelegate] - given new state is NULL, couldn't post update for 'EPBM4_Tmp_eth'**

and at the same time i can see my data getting published on the same topic from mosqiitto_sub.

Can anyone help me to solve this issue ?

2

You’ve shown us an Item configured for MQTT binding version 1.x
If you are in fact using that binding, you should probably show mqtt.cfg

A useful diagnostic technique is to link your same topic to a String type Item as well, so you can see the payload form and work out any parsing errors.