There’s a few options:
- Virtual Device: Use a Virtual Garage Door device with your smart home platform of choice. These map the status from your contact sensor into the Virtual Garage device and map the open/close actions from the Virtual Garage device to your momentary relay.
- Special Hyperlink: Use the Contact Sensor with the special
$.runRule("RULEID")
hyperlink syntax. With this approach, you would create a rule that sends the command to your momentary relay and use that Rule ID with the aforementioned special hyperlink syntax. - Super Tile: Use a Super Tile as James mentioned above which would allow you to display the status of the contact sensor while mapping the action to your momentary relay.