MockResponse(
        code = 302,
        headers = headersOf("Location", "/b"),
      ),
    )
    server.enqueue(MockResponse())

    val request = Request(server.url("/"))
    val call = client.newCall(request)
    val response = call.execute()

    assertThat(response.request.url.encodedPath).isEqualTo("/b")
    assertThat(response.request.headers).isEqualTo(headersOf())
  }

package(
    # copybara:uncomment default_applicable_licenses = ["//tensorflow:license"],
    licenses = ["notice"],
)

# Currently pybind extension shared objects must use only C API headers since
# the C API has static initializers duplicated in the Python bindings. So we
# need a second rule that omits .cc files, in
# tensorflow/python:_pywrap_parallel_device.
filegroup(
    name = "lib_headers",

        .url(server.url("/"))
        .header("Accept", "text/plain")
        .build()
    val response = client.newCall(request).execute()
    assertThat(response.code).isEqualTo(200)
    assertThat(response.body.string()).isEqualTo("hello, OkHttp")

    val recorded = server.takeRequest()
    assertThat(recorded.headers["Accept"]).isEqualTo("text/plain")
    assertThat(recorded.headers["Accept-Encoding"]).isEqualTo("gzip")

@needs_py310
@pytest.mark.parametrize(
    "path,headers,expected_status,expected_response",
    [
        ("/items", None, 200, {"User-Agent": "testclient"}),
        ("/items", {"X-Header": "notvalid"}, 200, {"User-Agent": "testclient"}),
        ("/items", {"User-Agent": "FastAPI test"}, 200, {"User-Agent": "FastAPI test"}),
    ],
)
def test(path, headers, expected_status, expected_response, client: TestClient):

      Request.Builder()
        .url(server.url("/"))
        .header("Connection", "close")
        .build()
    val requestB = Request(server.url("/"))
    assertConnectionNotReused(requestA, requestB)
  }

  @Test
  fun connectionsAreNotReusedWithResponseConnectionClose() {
    server.enqueue(
      MockResponse(
        headers = headersOf("Connection", "close"),
        body = "a",
      ),
    )

  var canUseHeaderValue = true
  var headerValue: String? = null

  loop@ for (i in 0 until headers.size) {
    val name = headers.name(i)
    val value = headers.value(i)

    when {
      name.equals("Cache-Control", ignoreCase = true) -> {
        if (headerValue != null) {
          // Multiple cache-control headers means we can't use the raw value.
          canUseHeaderValue = false
        } else {

			continue
		}
		t.Run(fmt.Sprintf("%d-locks", locks), func(t *testing.T) {
			// Number of readers per lock...
			for _, readers := range []int{1, 10, 100} {
				if locks > 1000 && readers > 1 {
					continue
				}
				if testing.Short() && readers > 10 {
					continue
				}
				t.Run(fmt.Sprintf("%d-read", readers), func(t *testing.T) {
					l := newLocker()
					for i := 0; i < locks; i++ {
						var tmp [16]byte

		}
	}
}

// Tests validate metadata extraction from http headers.
func TestExtractMetadataHeaders(t *testing.T) {
	testCases := []struct {
		header     http.Header
		metadata   map[string]string
		shouldFail bool
	}{
		// Validate if there a known 'content-type'.
		{
			header: http.Header{
				"Content-Type": []string{"image/png"},
			},
			metadata: map[string]string{

def test_get_invalid_one_header_items(client: TestClient):
    response = client.get("/items/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}


@needs_py39
def test_get_invalid_one_users(client: TestClient):
    response = client.get("/users/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text

* 创建一个允许的源列表（由字符串组成）。
* 将其作为「中间件」添加到你的 **FastAPI** 应用中。

你也可以指定后端是否允许：

* 凭证（授权 headers，Cookies 等）。
* 特定的 HTTP 方法（`POST`，`PUT`）或者使用通配符 `"*"` 允许所有方法。
* 特定的 HTTP headers 或者使用通配符 `"*"` 允许所有 headers。

```Python hl_lines="2  6-11  13-19"
{!../../docs_src/cors/tutorial001.py!}
```

默认情况下，这个 `CORSMiddleware` 实现所使用的默认参数较为保守，所以你需要显式地启用特定的源、方法或者 headers，以便浏览器能够在跨域上下文中使用它们。

支持以下参数：