Function configureServer

packages/vite/hmr/server/websocket.ts:2405–5057

(server)

		apply: 'serve',

		configureServer(server) {
			pluginRoot = (server as any).config?.root || process.cwd();
			const httpServer = server.httpServer;
			if (!httpServer) return;

			// Attempt early vendor manifest bootstrap once per server.
			if (!vendorBootstrapDone) {
				vendorBootstrapDone = true;
				const root = (server as any).config?.root || process.cwd();
				const existing = getVendorManifest();
				if (!existing) {
					const loaded = loadPrebuiltVendorManifest(root, verbose);
					if (!loaded && verbose) {
						console.warn('[hmr-ws][vendor] No vendor manifest found during bootstrap. Consider enabling vendorManifestPlugin earlier.');
					}
				} else if (verbose) {
					console.log('[hmr-ws][vendor] Manifest already present with', Object.keys(existing.modules).length, 'modules');
				}
				(globalThis as any).__NS_VENDOR_MANIFEST__ = getVendorManifest();
			}

			// Disable perMessageDeflate to avoid any extension negotiation quirks with native clients
			wss = new WebSocketServer({
				noServer: true,
				path: '/ns-hmr',
				perMessageDeflate: false,
			});

			if (verbose) {
				console.log('[hmr-ws] WebSocket configured on /ns-hmr');
			}

			httpServer.on('upgrade', (request, socket, head) => {
				try {
					if (verbose) {
						const ra = (request.socket as any)?.remoteAddress;
						const rp = (request.socket as any)?.remotePort;
						console.log('[hmr-ws][upgrade]', request.url, 'from', ra + (rp ? ':' + rp : ''));
					}
				} catch {}
				const pathname = new URL(request.url || '', 'http://localhost').pathname;
				if (pathname === '/ns-hmr') {
					wss?.handleUpgrade(request, socket, head, (ws) => {
						wss?.emit('connection', ws, request);
					});
				}
			});

			// Additional connection diagnostics
			wss.on('connection', (ws, req) => {
				try {
					if (verbose) {
						const ra = (req.socket as any)?.remoteAddress;
						const rp = (req.socket as any)?.remotePort;
						console.log('[hmr-ws] Client connected', ra + (rp ? ':' + rp : ''));
					}
				} catch {}
			});