ThingFacet is a reusable TQL component that defines the software interactions with a "thing" and represent the "thing" in the software. A "thing" can be sensors, actuators, devices, or a particular aspect or function of a more complex machine. A ThingFacet has a name, Model Attributes and Actions.
Attributes
Attributes are containers of values. They can be used for the following purposes in ThingFacets:
(1) Store parameters required to make a protocol specific invocation to the thing, such as ___as <String Name="InterfacePort"/>
(2) Store information received from the thing, such as <Number Name="TempValue"/> (The TempValue from the temperature sensor)
(3) Hold fixed information about the thing, such as <String Name="Unit" default="Celsius"/>
(4) Act as control variables - variable that can activate certain actions
hold fixed information about the thing, such as the temperature unit
Action is where the processes to interact with things are defined.
The control variables in the ThingFacet are . They are called "actionable attributes". Actionable attributes are linked with one or more actions in the same ThingFacet by a modifier "KnownBy". For example: <Number Name="TempValue" KnownBy="SerialReadAction"/>
Actions
Action is where the processes to interact with things are defined.
Gliffy name ThingFacet
An example of Camera ThingFacet.