MQTT publish automation, need help

mattlward · February 8, 2018, 4:31am

I have a few Wemos units with displays and I would like to configure the “Generic - MQTT Import” sensor to receive a broadcast of sorts that contains the real temperature and feels like temperature to the units to display. I have the units set up to receive traffic and that part works fine.

I am having trouble with the following automation:

- id: "Broadcast Real Temp MQTT"
  alias: 'Broadcast Real Temp MQTT'
  trigger:
    - platform: time
      minutes: '/1'
      seconds: '0'
  action:
    service: mqtt.publish
    data_template:
      payload_template: '{{ sensor.pws_temp_f.payload }}'
      topic: 'Real'

My goal is to transmit the temperature to the topic “Real”, every X number of minutes.
I am getting the following errors every interval:

018-02-07 22:30:00 ERROR (MainThread) [homeassistant.helpers.service] Error rendering data template: UndefinedError: 'sensor' is undefined
2018-02-07 22:30:00 ERROR (MainThread) [homeassistant.core] Invalid service data for mqtt.publish: required key not provided @ data['topic']. Got None

The sensor in the States panel is:

sensor.pws_temp_f

with a numeric value containing a decimal.
I know I have something screwed up in the template or maybe I need to template the topic some how…

Thanks Matt

keithh666 · February 8, 2018, 4:35am

I think this sensor.pws_temp_f should be states.sensor.pws_temp_f.state

mattlward · February 8, 2018, 4:41am

You are awesome! It works. I have been reading about templates and I just don’t get it. I am not a programmer, that does not help!

keithh666 · February 8, 2018, 4:43am

glad you got it working BTW hit the solution icon to show others how to fix it.

jaysix79 · February 8, 2018, 5:32am

do you mind sharing how you setup you mqtt settings??

mattlward · February 8, 2018, 1:18pm

Not at all… do you mean the broker or the automation or the code on the device catching the broadcast?

jaysix79 · February 10, 2018, 4:06pm

i would probably say all… since i been trying this for a week now without success… maybe i can start fresh

jaysix79 · February 10, 2018, 4:06pm

if you want i can post mine and maybe you can spot what am i missing

mattlward · February 10, 2018, 7:31pm

It is probably more lines than are really needed, but could not add the second service line to the first automation without a duplicate error. These are in an automation file, so you would need to format it for use in the configuration.yaml

This works well though

- id: "Broadcast Real Temp MQTT"
  alias: 'Broadcast Real Temp MQTT'
  trigger:
    - platform: time
      minutes: '/3'
      seconds: '0'
  action:
    service: mqtt.publish
    data_template:
      payload_template: '{{ states.sensor.pws_temp_f.state }}'
      topic: 'Real'
 
- id: "Broadcast Feels Like Temp MQTT"
  alias: 'Broadcast Feels Like Temp MQTT'
  trigger:
    - platform: time
      minutes: '/3'
      seconds: '0'
  action:
    service: mqtt.publish
    data_template:
      payload_template: '{{ states.sensor.pws_feelslike_f.state }}'
      topic: 'FeelsLike'

mattlward · February 10, 2018, 9:52pm

I am using Wemos D1’s to receive the “broadcast”. The Wemos units are running ESPEasy and I have defined a device as MQTT Sniffer and it detects the MQTT topic and pulls out the payload and then displays it on the little Wemos display.

Hope this helps, it is a very handy addition to a Wemos stack!

Wemos sniffer:

Wemos modules:

Wemos display setting:

jaysix79 · February 11, 2018, 2:40am

thank you let me try this settings out