# Frontend Example (Operator UI)
URL: /examples/frontend-example
The upstream frontend_example.py — start StationServer on port 4444, launch the browser Operator UI, and run the same test five times in a row with a DUT ID prompt between runs.
The minimal Operator UI setup: a station server, the browser launcher, and a loop that runs the test repeatedly so the station stays up between units. Based on `examples/frontend_example.py`.
The default browser opens `http://localhost:4444`, shows the station, and prompts for a DUT ID. Enter one in the browser or the console; the phase runs, the result appears in the history panel, and the prompt returns for the next unit. After five units the server stops.
The server reads its port from configuration. Default `0` picks a free port, which is fine for a bench but not for a bookmarked URL. Configuration →
Starts the Tornado server in a background thread and stops it on exit. Optional `history_path` shows past JSON records in the UI. Operator UI →
Opens the URL in the default browser. Omit it on a kiosk that already points a browser at the station.
An output callback that pushes the finished record to the UI's history. Without it the UI only shows the live test.
`execute()` runs one DUT. A production station loops forever (`while True`) and lets the operator abort with Ctrl-C.
The UI is served on `localhost` without authentication. To reach it from another machine bind the host's IP and firewall accordingly, or use the multi-station dashboard to list stations on the LAN.
For HTTPS, user accounts, multiple tests per station and searchable history across stations, TofuPilot's Operator UI runs the same script unchanged.
If the page is blank, see the FAQ.