One can associate multiple thing actions to a Thingfacet Attribute. You can do this by providing comma separated list of Action names. For example,
Assoicating Multiple Thing Actions
<String name="State" KnownBy="SyncImageAction,SyncPresetAction"/>
Multiple Thing Actions
<!-- Actions --> <Action Name="SyncPresetAction" Documentation="Synchronize camera state and preset"> <Workflow Limit="1" Live="1" Timeout="PT20S"> <Task Name="Main" While="true"> <Event Name="Argument" As="ActionArgument"/> <Invoke Name="SetPreset" waitFor="Argument" skip-if="[%:[:AA:].Preset/no-value(Value):%]" delayAfter="PT5S" get="[%:[:AA:].URL.Value:%]/cgi-bin/decoder_control.cgi?[:UP:][%:amp:%]command=15[%:amp:%]sit=[%:[:AA:].Preset.Value:%]"/> <Output name="Result" as="ActionResult"> <Value> <State> [%:[%:@Output:%]/if([:POK:]) then 'ON' else 'OFF':%]</State> <Preset>[%:[%:@Output:%]/if([:POK:]) then '[%:[:AA:].Preset.Value:%]' else null():%]</Preset> </Value> </Output> </Task> </Workflow> </Action> <Action name="SyncImageAction" documentation="Synchronize camera state and snapshot image"> <Workflow Limit="1" Live="1" Timeout="PT10S"> <Task name="Main" while="true"> <Event name="Argument" as="ActionArgument"/> <Invoke name="GetImage" waitFor="Argument" delay="PT1S" get="[%:[:AA:].URL.Value:%]/cgi-bin/video_snapshot.cgi?[:UP:]"/> <Output name="Result" as="ActionResult"> <Value> <State>[%:[%:@Output:%]/if([:IOK:]) then 'ON' else 'OFF':%]</State> <Image>[%:[%:@Output:%]/if([:IOK:]) then Invoke/GetImage/Message/Value/text() else '/img/no-image.jpg':%]</Image> </Value> </Output> </Task> </Workflow> </Action>
Here you can see two actions: SyncPresetAction and SyncImageActon which deal with camera preset and snapshot image respectively. Both as a result update the camera state.
In case when multiple attributes are updated, the system will select minimum number of actions with highest preference to perform the update[s]. That is, if only state needs to be updated, the engine will use SyncImageAction action and when both state and preset need updates, SyncPresetAction will be used.