}

  /** Use a proxy to fake IPv6 connectivity, even if localhost doesn't have IPv6.  */
  private fun configureClientAndServerProxies(http2: Boolean) {
    server.useHttps(handshakeCertificates.sslSocketFactory())
    server.protocols =
      when {
        http2 -> listOf(Protocol.HTTP_2, Protocol.HTTP_1_1)
        else -> listOf(Protocol.HTTP_1_1)
      }
    server.enqueue(
      MockResponse
        .Builder()

  private fun retryAfter(
    userResponse: Response,
    defaultDelay: Int,
  ): Int {
    val header = userResponse.header("Retry-After") ?: return defaultDelay

    // https://tools.ietf.org/html/rfc7231#section-7.1.3
    // currently ignores a HTTP-date, and assumes any non int 0 is a delay
    if (header.matches("\\d+".toRegex())) {
      return Integer.valueOf(header)
    }
    return Integer.MAX_VALUE
  }

  /** The HTTP {@code Host} header field name. */
  public static final String HOST = "Host";

  /**
   * The HTTP <a href="https://datatracker.ietf.org/doc/html/rfc7540#section-3.2.1">{@code
   * HTTP2-Settings} </a> header field name.
   *
   * @since 24.0
   */
  public static final String HTTP2_SETTINGS = "HTTP2-Settings";

  /** The HTTP {@code If-Match} header field name. */

import okhttp3.ResponseBody.Companion.asResponseBody
import okhttp3.ResponseBody.Companion.toResponseBody
import okhttp3.internal.authenticator.JavaNetAuthenticator
import okhttp3.internal.http2.Settings
import okhttp3.internal.proxy.NullProxySelector
import okhttp3.internal.tls.OkHostnameVerifier
import okhttp3.java.net.cookiejar.JavaNetCookieJar
import okhttp3.logging.HttpLoggingInterceptor

  val clientTestRule = configureClientTestRule()

  @RegisterExtension
  val testLogHandler: TestLogHandler = TestLogHandler(Http2::class.java)

  // Flaky https://github.com/square/okhttp/issues/4632
  // Flaky https://github.com/square/okhttp/issues/4633
  private val handshakeCertificates: HandshakeCertificates =
    platform.localhostHandshakeCertificates()

  @StartStop
  private val server = MockWebServer()

      headerEntries(
        ":method",
        "GET",
        ":scheme",
        "https",
        ":path",
        "/index.html",
        ":authority",
        "www.example.com",
        "custom-key",
        "custom-value",
      ),
    )
  }

  /**
   * http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-12#appendix-C.4
   */
  @Test

[graalvm]: https://www.graalvm.org/
[graalvm_21]: https://www.graalvm.org/release-notes/21_0/
[graalvm_22]: https://www.graalvm.org/release-notes/22_2/
[idna_15_1_0]: https://www.unicode.org/reports/tr46/#Modifications
[kotlin_1_4_20]: https://github.com/JetBrains/kotlin/releases/tag/v1.4.20
[kotlin_1_5_31]: https://github.com/JetBrains/kotlin/releases/tag/v1.5.31

    } catch (expected: UnknownHostException) {
    }
    applicationLogs
      .assertLogEqual("--> GET $url")
      .assertLogMatch(Regex("""<-- HTTP FAILED: java.net.UnknownHostException: reason. $url \(\d+ms\)"""))
      .assertNoMoreLogs()
  }

  @Test
  fun http2() {
    server.useHttps(handshakeCertificates.sslSocketFactory())
    url = server.url("/")
    setLevel(Level.BASIC)
    server.enqueue(MockResponse())

 [https_server_sample]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/HttpsServer.java
 [jetty_8_252]: https://webtide.com/jetty-alpn-java-8u252/
 [junit_5_rules]: https://junit.org/junit5/docs/current/user-guide/#migrating-from-junit4-rulesupport
 [major_versions]: https://jakewharton.com/java-interoperability-policy-for-major-version-updates/

HTTPS
=====

OkHttp attempts to balance two competing concerns:

 * **Connectivity** to as many hosts as possible. That includes advanced hosts that run the latest versions of [boringssl](https://boringssl.googlesource.com/boringssl/) and less out of date hosts running older versions of [OpenSSL](https://www.openssl.org/).