Remote Buttons & Triggers

Everything about triggering Photobooth via hardware buttons or remote calls.

1) Local browser hotkeys (simple HID to browser)

  • Connect the HID to the device running the browser.
  • Adminpanel → set per-action key codes: Picture/Collage/Print/Video/Custom → “Key code which triggers …”.
  • Browser window must be focused; Photobooth listens for JavaScript keyup keyCode.

2) Direct USB HID on the Photobooth host (no browser focus)

The remotebuzzer server reads a Linux input device and maps EV_KEY codes to your action key codes.

How it works

  • Remotebuzzer opens /dev/input/... (e.g. /dev/input/by-id/...-event-kbd).
  • Incoming key codes are matched against picture.key, collage.key, print.key, video.key, custom.key.
  • On match, the corresponding action is triggered for all connected clients.

Requirements

  • Remotebuzzer server enabled (Adminpanel → Hardware Button → Start remote buzzer Server).
  • Hardware Buttons enabled and the target action enabled.
  • HID device visible under /dev/input/... and readable by the remotebuzzer process.

Configure

1) Find device: ls -l /dev/input/by-id → choose the -event-kbd (or your HID). 2) Set Hardware Button → Input device to that path. 3) Set per-action key codes (Linux key codes, e.g. sudo showkey -k → 108). 4) Save and restart the remotebuzzer server.

Permissions

  • Many devices are root:input with crw-r-----. Give the Photobooth user read access:
  • add user to input group (sudo usermod -a -G input www-data + restart), or
  • udev rule to set group/mode for this device
  • find the device under /dev/input/by-id (e.g. ls -l /dev/input/by-id | grep event) and pick the matching -event-kbd (keyboard-like HID) symlink

udev rule example

  • Create /etc/udev/rules.d/99-photobooth-input.rules (adjust as needed):

  • General rule (applies to all input event nodes):

    • KERNEL=="event*", SUBSYSTEM=="input", MODE="660", GROUP="input"

  • Apply: sudo udevadm control --reload && sudo udevadm trigger

  • Ensure your Photobooth user is in the chosen group (e.g. input) or change GROUP to your service user.

Test

  • Remotebuzzer log: Listening for USB input on [...] keycodes [...].
  • Press button → log triggering action [picture] → workflow starts.

Notes

  • Remotebuzzer must be running and trigger must be armed (not already taking a picture).
  • Uses key press (value 1); key repeat will also trigger.

3) Remote trigger via Socket.io

  • Channel: photobooth-socket
  • Commands: start-picture, start-collage, collage-next, start-custom, start-video, print, rotary-cw, rotary-ccw, rotary-btn-press, move2usb
  • Response: completed after the workflow finishes.

4) Remote trigger via simple web requests (HTTP)

  • Depends on the socket.io implementation; requires Hardware Button → Enable Hardware Buttons and Hardware Button → Remote buzzer Server IP to be set.
  • Photobooth can start the Remotebuzzer server itself (enable Hardware Button → Start remote buzzer Server in Adminpanel).
  • Enable Hardware Buttons and set Remotebuzzer IP/Port.
  • Base URL: http://[Server IP]:[Port]
  • Available endpoints (depending on enabled features and buttons):
  • [Base URL]/ Simple help page with all available endpoints
  • [Base URL]/commands/start-picture
  • [Base URL]/commands/start-collage
  • [Base URL]/commands/start-custom
  • [Base URL]/commands/start-print
  • [Base URL]/commands/start-video
  • [Base URL]/commands/start-move2usb
  • [Base URL]/commands/reboot-now
  • [Base URL]/commands/shutdown-now
  • [Base URL]/commands/rotary-cw
  • [Base URL]/commands/rotary-ccw
  • [Base URL]/commands/rotary-btn-press
  • Example: curl http://<IP>:<PORT>/commands/start-picture
  • IP/Port notes:
  • [Hardware Button Server IP] must match Hardware Button → Remote buzzer Server IP (typically the Photobooth host IP).
  • [Hardware Button Server Port] is the Hardware Button → Enable Hardware Buttons value.
  • Common hardware for HTTP triggers: myStrom WiFi Button, Shelly Button, ESP32/ESP8266, Raspberry Pi Pico/Pico W (see examples below).

5) Hardware button examples (HTTP)

Troubleshooting

  • Remotebuzzer running and reachable; avoid 127.0.0.1 for remote clients—use the host IP.
  • Trigger affects all connected clients simultaneously.
  • Increase Photobooth loglevel (Adminpanel → General) and check Debugpanel; for HTTP/web triggers also check the browser console/network tab.
  • Fallback re-arms after a timeout if no completed arrives (fixed 60s; not configurable via UI).
  • Avoid loopback for cross-device use; use host IP/hostname. Every trigger hits all connected clients at once—plan accordingly.