@app.websocket("/items/{item_id}/ws")
async def websocket_endpoint(
    websocket: WebSocket,
    item_id: str,
    q: int | None = None,
    cookie_or_token: str = Depends(get_cookie_or_token),
):
    await websocket.accept()
    while True:
        data = await websocket.receive_text()
        await websocket.send_text(
            f"Session cookie or query token value is: {cookie_or_token}"
        )
        if q is not None:

* `allow_headers` – Eine Liste von HTTP-Requestheadern, die für Cross-Origin-Requests unterstützt werden sollten. Standardmäßig `[]`. Sie können `['*']` verwenden, um alle Header zu erlauben. Die Header `Accept`, `Accept-Language`, `Content-Language` und `Content-Type` sind immer für <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS#simple_requests" class="external-link" rel="noopener" target="_blank">einfache CORS-Requests</a> erlaubt.

@app.websocket("/items/{item_id}")
async def websocket_item(item_id: str, websocket: WebSocket):
    route: APIWebSocketRoute = websocket.scope["route"]
    await websocket.accept()
    await websocket.send_json({"item_id": item_id, "path": route.path})


client = TestClient(app)


def test_get():
    response = client.get("/users/rick")

* `allow_credentials` - 指示跨域请求支持 cookies。默认是 `False`。另外，允许凭证时 `allow_origins` 不能设定为 `['*']`，必须指定源。
* `expose_headers` - 指示可以被浏览器访问的响应头。默认为 `[]`。
* `max_age` - 设定浏览器缓存 CORS 响应的最长时间，单位是秒。默认为 `600`。

中间件响应两种特定类型的 HTTP 请求……

### CORS 预检请求

这是些带有 `Origin` 和 `Access-Control-Request-Method` 请求头的 `OPTIONS` 请求。

async def websocket_endpoint(
    *,
    websocket: WebSocket,
    item_id: str,
    q: Union[int, None] = None,
    cookie_or_token: Annotated[str, Depends(get_cookie_or_token)],
):
    await websocket.accept()
    while True:
        data = await websocket.receive_text()
        await websocket.send_text(
            f"Session cookie or query token value is: {cookie_or_token}"
        )
        if q is not None:

     *
     * @param loadTime the number of nanoseconds the cache spent computing or retrieving the new
     *     value
     */
    @SuppressWarnings("GoodTime") // should accept a java.time.Duration
    void recordLoadSuccess(long loadTime);

    /**
     * Records the failed load of a new entry. This should be called when a cache request causes an

     * GET
     * 2
     * Accept-Language: fr-CA
     * Accept-Charset: UTF-8
     * HTTP/1.1 200 OK
     * 3
     * Content-Type: image/png
     * Content-Length: 100
     * Cache-Control: max-age=600
     * ```
     *
     * A typical HTTPS file looks like this:
     *
     * ```
     * https://google.com/foo
     * GET
     * 2
     * Accept-Language: fr-CA
     * Accept-Charset: UTF-8

      }
    }
  }

  private fun readAndWriteFrames() {
    check(socket == null)
    val socket = serverSocket!!.accept()!!
    this.socket = socket

    // Bail out now if this instance was closed while waiting for the socket to accept.
    synchronized(this) {
      if (executor.isShutdown) {
        socket.close()
        return
      }
    }

   * empty list of cookies for the network request.
   *
   * Simple implementations will return the accepted cookies that have not yet expired and that
   * [match][Cookie.matches] [url].
   */
  fun loadForRequest(url: HttpUrl): List<Cookie>

  companion object {
    /** A cookie jar that never accepts any cookies. */
    @JvmField
    val NO_COOKIES: CookieJar = NoCookies()

    private class NoCookies : CookieJar {

import okhttp3.FallbackTestClientSocketFactory.Companion.TLS_FALLBACK_SCSV

/**
 * An SSLSocketFactory that delegates calls. Sockets created by the delegate are wrapped with ones
 * that will not accept the [TLS_FALLBACK_SCSV] cipher, thus bypassing server-side fallback
 * checks on platforms that support it. Unfortunately this wrapping will disable any
 * reflection-based calls to SSLSocket from Platform.
 */