Send value to mqtt

1

Hey I want to send some values from wheather app to mqtt broker. How to create the topic and how to send ?
Thank you

2

Is this openHAB related?

You don’t create topics. When you publish a message to a topic, if it doesn’t exist it will be created.

To send a message, it depends. If you are using the OH MQTT binding and a Generic MQTT Thing you configure a Channel with a commandTopic and anything you send to an Item linked to that Channel will be published to that topic.

Alternatively you can use the publishMQTT() Thing action from a rule.

3

Thank you. Is it correct that when I link an item to the channel of the mqtt think the values are not published when changing ? What to do ? Defining a rule ?

4

You have to use the sendCommand method to actually send a command or value to the linked addon.

If you get the value from another openHAB addon, use profile="system:follow" at the link to mqtt. This profile will issue a sendCommand to this specific Channel for each update from another linked channel or the item itself.
If you want to use a rule, simply use myItem.sendCommand(value) instead of myItem.postUpdate(value)

5

Thank you very much. The problem is solved !:+1::+1:
BLEIBEN SIE GESUND Klaus-Dieter Brinkmann

6

Isn’t that supposed to be profile=system:follow now?

1 Like
7

Yes, typo… Thanks for the hint :slight_smile:

However, the format is dependent of the way to configure… there is no code view for profile (yet), but I’m used to define such things via .items files.

EDIT: My bad… yes, missing system:…

So profile="system:follow" is valid :slight_smile:

8

is profile="follow" now no longer valid?

9

According to docs it’s system:follow

10

Yes, but a simple “follow” would also work. Core will prepend the “system:” in front of it for you. But I guess it does issue kind of a warning in the log about it.

11

Then maybe it’s worth to clarify in documentation, that, if no section is applied, openHAB will assume system:?