public val settings: Settings

  public constructor(
    code: Int = 200,
    headers: Headers = headersOf(),
    body: String = "",
  ) : this(
    Builder()
      .code(code)
      .headers(headers)
      .body(body),
  )

  private constructor(builder: Builder) {
    this.status = builder.status
    this.headers = builder.headers
    this.trailers = builder.trailers
    this.body = builder.body

  @Test fun basicChallenge() {
    val headers =
      Headers
        .Builder()
        .add("WWW-Authenticate: Basic realm=\"protected area\"")
        .build()
    assertThat(headers.parseChallenges("WWW-Authenticate"))
      .isEqualTo(listOf(Challenge("Basic", mapOf("realm" to "protected area"))))
  }

  @Test fun basicChallengeWithCharset() {
    val headers =
      Headers
        .Builder()

    assertThat(connect.headers["Private"]).isNull()
    assertThat(connect.headers["User-Agent"]).isEqualTo(USER_AGENT)
    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")

    val expected = Date(0L)
    val headers =
      Headers
        .Builder()
        .add("testDate", expected)
        .build()
    assertThat(headers["testDate"]).isEqualTo("Thu, 01 Jan 1970 00:00:00 GMT")
    assertThat(headers.getDate("testDate")).isEqualTo(Date(0L))
  }

  @Test fun addInstant() {
    val expected = Instant.ofEpochMilli(0L)
    val headers =
      Headers
        .Builder()

  @JvmName("-deprecated_getHeaders")
  @Deprecated(
    message = "moved to var",
    replaceWith = ReplaceWith(expression = "headers"),
    level = DeprecationLevel.ERROR,
  )
  fun getHeaders(): Headers = headers

  fun setHeaders(headers: Headers) = apply { this.headers = headers }

  @JvmName("-deprecated_getTrailers")
  @Deprecated(
    message = "moved to var",

**FastAPI** will **extract** the data for **each field** from the **headers** in the request and give you the Pydantic model you defined.

## Check the Docs { #check-the-docs }

You can see the required headers in the docs UI at `/docs`:

<div class="screenshot">
<img src="/img/tutorial/header-param-models/image01.png">
</div>

## Forbid Extra Headers { #forbid-extra-headers }

  }

  class Part private constructor(
    @get:JvmName("headers") val headers: Headers?,
    @get:JvmName("body") val body: RequestBody,
  ) {
    @JvmName("-deprecated_headers")
    @Deprecated(
      message = "moved to val",
      replaceWith = ReplaceWith(expression = "headers"),
      level = DeprecationLevel.ERROR,
    )
    fun headers(): Headers? = headers

    @JvmName("-deprecated_body")
    @Deprecated(

    assert response.headers["content-type"] == json_type


def test_router_a_a_override():
    with client:
        response = client.get("/a/a/override")
    assert response.content == b"Hello A A"
    assert response.headers["content-type"] == text_type


def test_router_a_b():
    with client:
        response = client.get("/a/b")
    assert response.content == b"Hello A B"

      for (i in 0 until headers.size) {
        // header names must be lowercase.
        val name = headers.name(i).lowercase(Locale.US)
        if (name !in HTTP_2_SKIPPED_REQUEST_HEADERS ||
          name == TE &&
          headers.value(i) == "trailers"
        ) {
          result.add(Header(name, headers.value(i)))
        }
      }
      return result
    }

// getCanonicalHeaders generate a list of request headers with their values
func getCanonicalHeaders(signedHeaders http.Header) string {
	var headers []string
	vals := make(http.Header, len(signedHeaders))
	for k, vv := range signedHeaders {
		k = strings.ToLower(k)
		headers = append(headers, k)
		vals[k] = vv
	}
	sort.Strings(headers)

	var buf bytes.Buffer
	for _, k := range headers {
		buf.WriteString(k)
		buf.WriteByte(':')