WebRtcUrlConfig.position is declared in types but never read — archive playback silently falls back to live

[revz143]

Package: @networkoptix/webrtc-stream-manager@0.1.29

WebRtcUrlConfigUnknown declares position?: number (dist/types/types.d.ts), but the implementation never reads it. StreamManager.buildSignalingUrl only appends positionMs= from the singleton-global _currentPosition (set via StreamManager.updatePosition()):

// dist/lib/core/stream-manager.js (buildSignalingUrl)
if (this._currentPosition) {
    params.push(`positionMs=${this._currentPosition}`);
}

A grep of dist/lib for urlConfig.position / config.position returns zero hits. So passing position on the connect config compiles fine and silently produces a live stream.

Steps to reproduce

const connection = StreamManager.getInstance().connect({
  systemId, cameraId, accessToken,
  apiVersion: ApiVersions.v2,
  targetStream: TargetStream.AUTO,
  position: 1712345678000, // epoch ms, in the past, footage exists
}, videoElement);

Expected: archive playback from the given position (v1 behavior — position was baked into the signaling URL).

Actual: live stream; signaling URL contains no positionMs.

Why the global workaround is insufficient

StreamManager.updatePosition() is process-global while the signaling URL is rebuilt lazily per connection attempt, including internal retries. With concurrent players (e.g. a live grid plus an archive dialog), any live connection that retries while the global is set reconnects into archive — and clearing the global after connect makes the archive connection's own retries come back live. Per-connection position is not expressible.

The post-connect path also can't cover the initial position: connect() applies _currentPosition via connection.updatePosition() immediately after construction, but sendSeek silently no-ops until the data channel is open.

Suggested fix

In buildSignalingUrl, honor the per-connection config with the global as fallback:

const positionMs = urlConfig.position ?? this._currentPosition;
if (positionMs) {
    params.push(`positionMs=${positionMs}`);
}

The closure in connect() already captures urlConfig per connection, so retries keep the correct per-connection position. We're running exactly this as a local patch and can confirm it restores archive playback.

Environment

• @networkoptix/webrtc-stream-manager 0.1.29 (v2 native API)
• Playback via cloud relay ({systemId}.relay.vmsproxy.com), useRelayPrefix: false
• Chrome / Edge (Chromium)