}

// Return canonical headers.
func canonicalizedAmzHeadersV2(headers http.Header) string {
	var keys []string
	keyval := make(map[string]string, len(headers))
	for key := range headers {
		lkey := strings.ToLower(key)
		if !strings.HasPrefix(lkey, "x-amz-") {
			continue
		}
		keys = append(keys, lkey)
		keyval[lkey] = strings.Join(headers[key], ",")
	}
	sort.Strings(keys)

//
// Header specification:
// Continuation messages contain two headers, as follows:
// https://docs.aws.amazon.com/AmazonS3/latest/API/images/s3select-frame-diagram-cont.png
//
// Payload specification:
// Continuation messages have no payload.
var continuationMessage = []byte{
	0, 0, 0, 57, // total byte-length.
	0, 0, 0, 41, // headers byte-length.
	139, 161, 157, 242, // prelude crc.

	rw := httptest.NewRecorder()
	trw := &trackingResponseWriter{ResponseWriter: rw}

	if headersAlreadyWritten(trw) {
		t.Fatal("headers have not been written yet")
	}

	trw.WriteHeader(123)
	if !headersAlreadyWritten(trw) {
		t.Fatal("headers were written")
	}
}

func TestHeadersAlreadyWrittenWrapped(t *testing.T) {
	rw := httptest.NewRecorder()

	}
	extractedSignedHeaders := make(http.Header)
	for _, header := range signedHeaders {
		// `host` will not be found in the headers, can be found in r.Host.
		// but its always necessary that the list of signed headers containing host in it.
		val, ok := reqHeaders[http.CanonicalHeaderKey(header)]
		if !ok {
			// try to set headers from Query String
			val, ok = reqQueries[header]
		}
		if ok {

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: str | None = None
    traceparent: str | None = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: CommonHeaders = Header(convert_underscores=False)):

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: str | None = None
    traceparent: str | None = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(
    headers: Annotated[CommonHeaders, Header(convert_underscores=False)],
):

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: Union[str, None] = None
    traceparent: Union[str, None] = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: Annotated[CommonHeaders, Header()]):

    assertThat(cacheControl.toString()).isEqualTo(header)
  }

  @Test
  @Throws(Exception::class)
  fun parseIgnoreCacheControlExtensions() {
    // Example from http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9.6
    val header = "private, community=\"UCI\""
    val cacheControl =
      parse(
        Headers
          .Builder()
          .set("Cache-Control", header)
          .build(),
      )

//   - SSE-KMS
type Type interface {
	fmt.Stringer

	IsRequested(http.Header) bool
	IsEncrypted(map[string]string) bool
}

// IsRequested returns true and the SSE Type if the HTTP headers
// indicate that some form server-side encryption is requested.
//
// If no SSE headers are present then IsRequested returns false
// and no Type.
func IsRequested(h http.Header) (Type, bool) {
	switch {
	case S3.IsRequested(h):
		return S3, true

    val headers = response.headers
    assertThat(headers.size).isEqualTo(1)
    assertThat(headers.name(0)).isEqualTo(":version")
    assertThat(headers.value(0)).isEqualTo("HTTP/1.1")
  }

  @Test fun http2HeadersListDropsForbiddenHeadersHttp2() {
    val request =
      Request
        .Builder()
        .url("http://square.com/")
        .header("Connection", "upgrade")