How should a WoT Thing Description distinguish between properties that carry configuration state and properties that carry a sensor or actuator state?
The WoT Thing Description specification specifies three interaction affordances, Properties, Actions and Events. The property affordance is described as:
An Interaction Affordance that exposes state of the Thing. This state can then be retrieved (read) and optionally updated (write). Things can also choose to make Properties observable by pushing the new state after a change.
There is no mention of different types of states, eg sensors and actuators vs configuration.
Example 27 shows a TD of Thing that has an on/off switch, a brightness setting and a timer as follows.
"properties": {
"on": {
"type": "boolean",
"forms": [...]
},
"brightness": {
"type": "number",
"forms": [...]
},
"timer": {
"type": "integer",
"forms": [...]
}
},
To a consumer the on/off switch property "on" is clearly different from the brightness and timer properties. The "on" properties is used for day to day use while the brightness and timer are configurations that once set you leave alone. Yet how to distinguish this to the end-user.
Another example a ZWave zw100 multi sensor has temperature, motion, light, vibration and humidity sensors, about 20 read-only attributes and about 40 configuration values.
When presenting this Thing to an end-user the sensor values must be presented differently than the configuration values. You don't want to present a flat list of 60+ properties and let the user figure out what is what.
How does the specifications expect the TD to indicate the difference between properties that carry the value state vs properties for configuration state?