moq_native/
websocket.rs

1use anyhow::Context;
2use qmux::tokio_tungstenite;
3use std::collections::HashSet;
4use std::sync::{Arc, LazyLock, Mutex};
5use std::{net, time};
6use url::Url;
7
8// Track servers (hostname:port) where WebSocket won the race, so we won't give QUIC a headstart next time
9static WEBSOCKET_WON: LazyLock<Mutex<HashSet<(String, u16)>>> = LazyLock::new(|| Mutex::new(HashSet::new()));
10
11/// WebSocket configuration for the client.
12#[derive(Clone, Debug, clap::Args, serde::Serialize, serde::Deserialize)]
13#[serde(default, deny_unknown_fields)]
14#[non_exhaustive]
15pub struct ClientWebSocket {
16	/// Whether to enable WebSocket support.
17	#[arg(
18		id = "websocket-enabled",
19		long = "websocket-enabled",
20		env = "MOQ_CLIENT_WEBSOCKET_ENABLED",
21		default_value = "true"
22	)]
23	pub enabled: bool,
24
25	/// Delay in milliseconds before attempting WebSocket fallback (default: 200)
26	/// If WebSocket won the previous race for a given server, this will be 0.
27	#[arg(
28		id = "websocket-delay",
29		long = "websocket-delay",
30		env = "MOQ_CLIENT_WEBSOCKET_DELAY",
31		default_value = "200ms",
32		value_parser = humantime::parse_duration,
33	)]
34	#[serde(with = "humantime_serde")]
35	#[serde(skip_serializing_if = "Option::is_none")]
36	pub delay: Option<time::Duration>,
37}
38
39impl Default for ClientWebSocket {
40	fn default() -> Self {
41		Self {
42			enabled: true,
43			delay: Some(time::Duration::from_millis(200)),
44		}
45	}
46}
47
48pub(crate) async fn race_handle(
49	config: &ClientWebSocket,
50	tls: &rustls::ClientConfig,
51	url: Url,
52) -> Option<anyhow::Result<qmux::Session>> {
53	if !config.enabled {
54		return None;
55	}
56
57	// Only attempt WebSocket for HTTP-based schemes.
58	// Custom protocols (moqt://, moql://) use raw QUIC and don't support WebSocket.
59	match url.scheme() {
60		"http" | "https" | "ws" | "wss" => {}
61		_ => return None,
62	}
63
64	let res = connect(config, tls, url).await;
65	if let Err(err) = &res {
66		tracing::warn!(%err, "WebSocket connection failed");
67	}
68	Some(res)
69}
70
71pub(crate) async fn connect(
72	config: &ClientWebSocket,
73	tls: &rustls::ClientConfig,
74	mut url: Url,
75) -> anyhow::Result<qmux::Session> {
76	anyhow::ensure!(config.enabled, "WebSocket support is disabled");
77
78	let host = url.host_str().context("missing hostname")?.to_string();
79	let port = url.port().unwrap_or_else(|| match url.scheme() {
80		"https" | "wss" | "moql" | "moqt" => 443,
81		"http" | "ws" => 80,
82		_ => 443,
83	});
84	let key = (host, port);
85
86	// Apply a small penalty to WebSocket to improve odds for QUIC to connect first,
87	// unless we've already had to fall back to WebSockets for this server.
88	// TODO if let chain
89	match config.delay {
90		Some(delay) if !WEBSOCKET_WON.lock().unwrap().contains(&key) => {
91			tokio::time::sleep(delay).await;
92			tracing::debug!(%url, delay_ms = %delay.as_millis(), "QUIC not yet connected, attempting WebSocket fallback");
93		}
94		_ => {}
95	}
96
97	// Convert URL scheme: http:// -> ws://, https:// -> wss://
98	// Custom protocols (moqt://, moql://) use raw QUIC and don't support WebSocket.
99	let needs_tls = match url.scheme() {
100		"http" => {
101			url.set_scheme("ws").expect("failed to set scheme");
102			false
103		}
104		"https" => {
105			url.set_scheme("wss").expect("failed to set scheme");
106			true
107		}
108		"ws" => false,
109		"wss" => true,
110		_ => anyhow::bail!("unsupported URL scheme for WebSocket: {}", url.scheme()),
111	};
112
113	tracing::debug!(%url, "connecting via WebSocket");
114
115	// Use the existing TLS config (which respects tls-disable-verify) for secure connections
116	let connector = if needs_tls {
117		tokio_tungstenite::Connector::Rustls(Arc::new(tls.clone()))
118	} else {
119		tokio_tungstenite::Connector::Plain
120	};
121
122	let session = qmux::Client::new()
123		.with_config(qmux::tungstenite::protocol::WebSocketConfig {
124			max_message_size: Some(64 << 20), // 64 MB
125			max_frame_size: Some(16 << 20),   // 16 MB
126			accept_unmasked_frames: false,
127			..Default::default()
128		})
129		.with_connector(connector)
130		.connect(url.as_str())
131		.await
132		.context("failed to connect WebSocket")?;
133
134	tracing::warn!(%url, "using WebSocket fallback");
135	WEBSOCKET_WON.lock().unwrap().insert(key);
136
137	Ok(session)
138}
139
140/// Listens for incoming WebSocket connections on a TCP port.
141///
142/// Use with [`crate::Server::with_websocket`] to accept WebSocket connections
143/// alongside QUIC connections on a separate port.
144pub struct WebSocketListener {
145	listener: tokio::net::TcpListener,
146	server: qmux::Server,
147}
148
149impl WebSocketListener {
150	pub async fn bind(addr: net::SocketAddr) -> anyhow::Result<Self> {
151		let listener = tokio::net::TcpListener::bind(addr).await?;
152		let server = qmux::Server::new();
153		Ok(Self { listener, server })
154	}
155
156	pub fn local_addr(&self) -> anyhow::Result<net::SocketAddr> {
157		Ok(self.listener.local_addr()?)
158	}
159
160	pub async fn accept(&self) -> Option<anyhow::Result<qmux::Session>> {
161		match self.listener.accept().await {
162			Ok((stream, addr)) => {
163				tracing::debug!(%addr, "accepted WebSocket TCP connection");
164				let server = self.server.clone();
165				Some(
166					server
167						.accept(stream)
168						.await
169						.map_err(|e| anyhow::anyhow!("WebSocket accept failed: {e}")),
170				)
171			}
172			Err(e) => Some(Err(e.into())),
173		}
174	}
175}
moq_native/websocket.rs

moq_native/
websocket.rs
