HDMI-CEC REST Server

A very simplistic REST API to wake up or shutdown the monitor using HDMI CEC

Requires cec-utils (sudo apt get install cec-utils)

Example of usage:
curl -X POST http://<target_ip>:8181/screen/on wakes up the monitor on the target device
curl -X POST http://<target_ip>:8181/screen/off shuts down the monitor on the target device

More advanced example using presence detection under Home Assistant:
Note: This is has been developped to light on/off a TV with a Raspberry Pi depending on the Occupancy attribute of motion sensor which is controlled by Home Assistant. The HDMI-CEC-REST-Server runs on the rasperry pi while Home Assistant sends POSTs ON/OFF when the Occupancy attribute of the motion sensor changes so that the TV screen is on only when there's someone in the room.

1. Modify the Home Assistant principal configuration.yaml file. Add the following to the bottom of the file (or append an exisitng rest_command section):

rest_command:
  remotedevice_hdmi_on:
    url: "http://<target_ip>:8181/screen/on"
    method: POST
    headers:
      accept: "application/json, text/html"
      user-agent: "HAOS"
    verify_ssl: false
  remotedevice_hdmi_off:
    url: "http://<target_ip>:8181/screen/off"
    method: POST
    headers:
      accept: "application/json, text/html"
      user-agent: "HAOS"
    verify_ssl: false

2. Save and validate the configuration.yaml file uder developer-tools of Home Assistant then reboot.
3. Create the "ON" automation:

• Set the trigger to "occupancy becomes occupied" attribute of your motion sensor
• Set the action to rest_command.magicmirror_hdmi_on

4. Create the "OFF" automation:

• Set the trigger to "occupancy becomes unoccupied" attribute of your motion sensor
• Set the action to rest_command.magicmirror_hdmi_off

5. That's it ! The monitor of your target should wake up upon motion detection and shut down after 3mn of no motion detection.