createWebSocketServer() — vite Function Reference

Architecture documentation for the createWebSocketServer() function in ws.ts from the vite codebase.

Function typescript ViteCore ConfigEngine calls 4 called by 1

Entity Profile

ViteCore→ ConfigEngine→ createWebSocketServer() — vite Function Reference

Dependency Diagram

graph TD
  ed427876_97cc_17d4_d5e4_ae67bba950e3["createWebSocketServer()"]
  cab2c96f_4573_f58d_dd64_51e96c3e5033["ws.ts"]
  ed427876_97cc_17d4_d5e4_ae67bba950e3 -->|defined in| cab2c96f_4573_f58d_dd64_51e96c3e5033
  24ecf2a1_3c09_d451_76f3_9485b4e993f8["_createServer()"]
  24ecf2a1_3c09_d451_76f3_9485b4e993f8 -->|calls| ed427876_97cc_17d4_d5e4_ae67bba950e3
  2aff86e8_0c9d_22cb_6536_c1321e1aaa1d["isObject()"]
  ed427876_97cc_17d4_d5e4_ae67bba950e3 -->|calls| 2aff86e8_0c9d_22cb_6536_c1321e1aaa1d
  92168511_91a7_3f51_bfad_0ba065c191e7["hasValidToken()"]
  ed427876_97cc_17d4_d5e4_ae67bba950e3 -->|calls| 92168511_91a7_3f51_bfad_0ba065c191e7
  2e1469ca_9e59_dcc2_bdc7_05126c765fd0["error()"]
  ed427876_97cc_17d4_d5e4_ae67bba950e3 -->|calls| 2e1469ca_9e59_dcc2_bdc7_05126c765fd0
  743fd3ce_caa4_d18b_5e53_7a8e20b91e4c["normalizeHotChannel()"]
  ed427876_97cc_17d4_d5e4_ae67bba950e3 -->|calls| 743fd3ce_caa4_d18b_5e53_7a8e20b91e4c
  style ed427876_97cc_17d4_d5e4_ae67bba950e3 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

packages/vite/src/node/server/ws.ts lines 118–467

export function createWebSocketServer(
  server: HttpServer | null,
  config: ResolvedConfig,
  httpsOptions?: HttpsServerOptions,
): WebSocketServer {
  if (config.server.ws === false) {
    return {
      [isWebSocketServer]: true,
      get clients() {
        return new Set<WebSocketClient>()
      },
      async close() {
        // noop
      },
      on: noop as any as WebSocketServer['on'],
      off: noop as any as WebSocketServer['off'],
      setInvokeHandler: noop,
      handleInvoke: async () => ({
        error: {
          name: 'TransportError',
          message: 'handleInvoke not implemented',
          stack: new Error().stack,
        },
      }),
      listen: noop,
      send: noop,
    }
  }

  let wsHttpServer: Server | undefined = undefined

  const hmr = isObject(config.server.hmr) && config.server.hmr
  const hmrServer = hmr && hmr.server
  const hmrPort = hmr && hmr.port
  // TODO: the main server port may not have been chosen yet as it may use the next available
  const portsAreCompatible = !hmrPort || hmrPort === config.server.port
  const wsServer = hmrServer || (portsAreCompatible && server)
  let hmrServerWsListener: (
    req: InstanceType<typeof IncomingMessage>,
    socket: Duplex,
    head: Buffer,
  ) => void
  const customListeners = new Map<string, Set<WebSocketCustomListener<any>>>()
  const clientsMap = new WeakMap<WebSocketRaw, WebSocketClient>()
  const port = hmrPort || 24678
  const host = (hmr && hmr.host) || undefined
  const allowedHosts =
    config.server.allowedHosts === true
      ? config.server.allowedHosts
      : Object.freeze([...config.server.allowedHosts]) // Freeze the array to allow caching

  const shouldHandle = (req: IncomingMessage) => {
    const protocol = req.headers['sec-websocket-protocol']!
    // vite-ping is allowed to connect from anywhere
    // because it needs to be connected before the client fetches the new `/@vite/client`
    // this is fine because vite-ping does not receive / send any meaningful data
    if (protocol === 'vite-ping') return true

    if (
      allowedHosts !== true &&
      !isHostAllowed(req.headers.host, allowedHosts)
    ) {
      return false
    }

    if (config.legacy?.skipWebSocketTokenCheck) {
      return true
    }

    // If the Origin header is set, this request might be coming from a browser.
    // Browsers always sets the Origin header for WebSocket connections.
    if (req.headers.origin) {
      const parsedUrl = new URL(`http://example.com${req.url!}`)
      return hasValidToken(config, parsedUrl)
    }

    // We allow non-browser requests to connect without a token
    // for backward compat and convenience
    // This is fine because if you can sent a request without the SOP limitation,
    // you can also send a normal HTTP request to the server.
    return true