/video signaling proxy and a global public server http path config item

server/src/services/mediaMtxService/proxy.js

@@ -0,0 +1,69 @@
+// MediaMTX HTTP Proxy
+// Purpose: Exposes WHEP and WHIP signaling beneath the server-owned /video path while MediaMTX remains loopback-only.
+// Scope: Proxies signaling HTTP only; WebRTC media continues to travel directly through MediaMTX's ICE listener.
+const { createProxyMiddleware } = require('http-proxy-middleware');
+
+const PUBLIC_MEDIA_PREFIX = '/video';
+const INTERNAL_WEBRTC_ORIGIN = 'http://127.0.0.1:8889';
+const SIGNALING_TIMEOUT_MS = 60 * 60 * 1000;
+
+function rewriteSessionLocation(location, internalOrigin = INTERNAL_WEBRTC_ORIGIN) {
+  const value = String(location || '');
+  if (!value) return value;
+
+  /*
+    MediaMTX normally returns a root-relative WHEP/WHIP session URL. Browsers
+    subsequently PATCH and DELETE that exact Location, so restore the public
+    mount prefix that was removed before proxying the initial request.
+  */
+  if (value.startsWith('/') && !value.startsWith(`${PUBLIC_MEDIA_PREFIX}/`)) {
+    return `${PUBLIC_MEDIA_PREFIX}${value}`;
+  }
+
+  try {
+    const parsed = new URL(value);
+    if (parsed.origin === new URL(internalOrigin).origin) {
+      return `${PUBLIC_MEDIA_PREFIX}${parsed.pathname}${parsed.search}${parsed.hash}`;
+    }
+  } catch {
+    // A path relative to the WHEP/WHIP endpoint already resolves beneath
+    // /video in the browser and must not be converted into a root path.
+  }
+  return value;
+}
+
+function createMediaMtxProxy({ target = INTERNAL_WEBRTC_ORIGIN, logger = console } = {}) {
+  return createProxyMiddleware({
+    target,
+    changeOrigin: true,
+    proxyTimeout: SIGNALING_TIMEOUT_MS,
+    timeout: SIGNALING_TIMEOUT_MS,
+    logger,
+    on: {
+      proxyRes(proxyResponse) {
+        const location = proxyResponse.headers.location;
+        if (location) proxyResponse.headers.location = rewriteSessionLocation(location, target);
+      },
+      error(error, request, response) {
+        logger.warn?.('MediaMTX signaling proxy failed', {
+          method: request.method,
+          path: request.originalUrl || request.url,
+          error: error.message,
+        });
+        if (response.headersSent) {
+          response.destroy(error);
+          return;
+        }
+        response.writeHead(502, { 'Content-Type': 'text/plain; charset=utf-8', 'Cache-Control': 'no-store' });
+        response.end('Media signaling is temporarily unavailable.');
+      },
+    },
+  });
+}
+
+module.exports = {
+  INTERNAL_WEBRTC_ORIGIN,
+  PUBLIC_MEDIA_PREFIX,
+  createMediaMtxProxy,
+  rewriteSessionLocation,
+};