return headers...

 */
class Http2Reader(
  /** Creates a frame reader with max header table size of 4096. */
  private val source: BufferedSource,
  private val client: Boolean,
) : Closeable {
  private val continuation: ContinuationSource = ContinuationSource(this.source)
  private val hpackReader: Hpack.Reader =
    Hpack.Reader(
      source = continuation,
      headerTableSizeSetting = 4096,
    )

  value: String,
) = apply {
  headers[name] = value
}

fun Request.Builder.commonAddHeader(
  name: String,
  value: String,
) = apply {
  headers.add(name, value)
}

fun Request.Builder.commonRemoveHeader(name: String) =
  apply {
    headers.removeAll(name)
  }

fun Request.Builder.commonHeaders(headers: Headers) =
  apply {
    this.headers = headers.newBuilder()
  }

		return "", ErrMissingSignTag
	}
	if signFields[1] == "" {
		return "", ErrMissingFields
	}
	signature := signFields[1]
	return signature, ErrNone
}

// Parse slice of signed headers from signed headers tag.
func parseSignedHeader(signedHdrElement string) ([]string, APIErrorCode) {
	signedHdrFields := strings.Split(strings.TrimSpace(signedHdrElement), "=")
	if len(signedHdrFields) != 2 {

		}
	}
}

// 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{

from fastapi import Depends, FastAPI, Header, status
from fastapi.testclient import TestClient

app = FastAPI()


def get_header(*, someheader: str = Header()):
    return someheader


def get_something_else(*, someheader: str = Depends(get_header)):
    return f"{someheader}123"


@app.get("/")
def get_deps(dep1: str = Depends(get_header), dep2: str = Depends(get_something_else)):
    return {"dep1": dep1, "dep2": dep2}

  data?.let {
    request.method(requestMethod, it.toRequestBody(mediaType()))
  }

  for (header in headers.orEmpty()) {
    val parts = header.split(':', limit = 2)
    if (!isSpecialHeader(parts[0])) {
      request.header(parts[0], parts[1])
    }
  }
  referer?.let {
    request.header("Referer", it)
  }
  request.header("User-Agent", userAgent)

  return request.build()
}

    }
  }
  return null
}

internal fun Headers.Builder.commonAdd(
  name: String,
  value: String,
) = apply {
  headersCheckName(name)
  headersCheckValue(value, name)
  commonAddLenient(name, value)
}

internal fun Headers.Builder.commonAddAll(headers: Headers) =
  apply {
    for (i in 0 until headers.size) {
      commonAddLenient(headers.name(i), headers.value(i))
    }
  }

client = TestClient(app)


@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):

    assertThat(connect.headers["Proxy-Connection"]).isEqualTo("Keep-Alive")
    assertThat(connect.headers["Host"]).isEqualTo("android.com:443")
    val get = server.takeRequest()
    assertThat(get.headers["Private"]).isEqualTo("Secret")
    assertThat(get.headers["User-Agent"]).isEqualTo("App 1.0")
    assertThat(hostnameVerifier.calls).containsExactly("verify android.com")
  }

  /**