Start Server

Start the OVRTX Dev Variant Presenter server

The one rule

Start the server ONLY through the watchdog script — run_server.ps1 on Windows, run_server.sh on Linux/macOS:

powershell -ExecutionPolicy Bypass -File run_server.ps1

./run_server.sh

From an agent / automation, launch it detached so it keeps running:

Start-Process powershell -ArgumentList '-ExecutionPolicy','Bypass','-NoProfile','-File','run_server.ps1' -WorkingDirectory '<repo-root>' -WindowStyle Hidden

cd <repo-root> && mkdir -p logs && nohup ./run_server.sh > logs/watchdog.log 2>&1 &

Forbidden launch methods

• ❌ python -m dev_variant_presenter ... (bare) — no watchdog
• ❌ A generic preview/dev-server launcher — bare process; its stdout is discarded when it exits, so a crash leaves no logs
• ❌ A second browser tab / client — the WebRTC stream is single-client; a second client steals the active session (e.g. an in-progress recording)

Why: run_server.ps1 / run_server.sh are watchdogs. The ovrtx/ovstage/ovstream native layer hard-dies routinely (that's expected, not a bug). The watchdog (a) auto-relaunches on abnormal exit after 3s and (b) redirects stdout/stderr to logs/server_out.log / server_err.log. Launched WITHOUT it, a normal crash becomes a dead app with no recovery and no logs to diagnose from.

Before starting

1. Env exists: .venv\Scripts\python.exe (Windows) / .venv/bin/python (Linux/macOS) must be present. If not → use the setup-environment skill first.
2. No server already running: check http://127.0.0.1:8080/. If one responds — or an orphan from an old session is holding the port — STOP it first. Orphaned renderers keep the GPU hot and force the new server onto shifted ports. To stop cleanly: kill the watchdog process (run_server.ps1 / run_server.sh) FIRST (so it can't relaunch), THEN the python … -m dev_variant_presenter process(es). Watch for orphans on a different Python (e.g. system Python, not .venv).

Find the URL — the port is NOT always 8080

The control port defaults to 8080 but shifts to the next free port when 8080 is busy (and the WebRTC signaling port shifts the same way). Never assume 8080 — resolve the actual URL first, or a healthy server looks like a failed one:

• The watchdog prints it: *** OVRTX Dev Variant Presenter is up - open: <url> *** (in the console, or in the file the detached launch redirects to).
• The server also writes it to logs/server_url.txt on every launch (stale files are removed at launch, so the file appearing means this run).
• Fall back to http://127.0.0.1:8080 only if neither is available yet.

Use that resolved URL — call it $URL — for every check below.

Verify it came up

• Poll $URL until HTTP 200 — GPU warm-up can take ~30–90s. (logs/server_url.txt lands within ~1s of launch, well before the server answers.)
• Tail logs/server_out.log; wait for the stream to go live.
• Open $URL in ONE Chromium tab. Use 127.0.0.1, not localhost.

On crash

The watchdog relaunches automatically (3s) and the browser auto-reopens the last stage. Evidence: logs/server_out.log (+ logs/server_out.prev.log), exit lines in server_crashes.log. Avoid rapid kill/relaunch cycles — they can wedge the GPU/stream until a stage reopen.