Attributes over MQTT with plain values instead of JSON

Agents, Protocols and APIs
1

Hello there,

I currently have trouble connecting an attribute to an agent link (probably because of this bug: Adding attribute sometimes breaks · Issue #581 · openremote/openremote · GitHub) but in the meantime I want to setup my platform.

My edge device is sending informations about the attributes over MQTT. Each attribute has its own topic. But the thing I couldn’t find in the documentation is, if its possible that OR reads just the topic values instead of expecting an JSON?
Like for example on topic
master/mySensor/attribute/temperature/4aBjUwKqO3GNiScKgbJ475 the value 23.4 is posted.

Is this even possible or am I forced to send/expect JSON formatted values?

2

Hi,

Apologies for the delayed response; busy times at the moment.

The closest we have as described in the wiki article is:

{realm}/{clientId}/writeattributevalue/{attributeName}/{assetId} - Payload: JSON of attribute value

So the value goes in the body of the publish message which isn’t too different to putting it in the topic for numbers and/or booleans; like you say the data needs to be in JSON format; supporting values in the topic is of limited value when using other JSON data types but if you provide more details about why this would be useful we can always consider it.

There is also the possibility of writing some java code to add a custom MQTT handler which can process topics and payload however you want.