@Tag("Slowish")
class DnsOverHttpsTest {
  @RegisterExtension
  val platform = PlatformRule()

  @StartStop
  private val server = MockWebServer()

  private lateinit var dns: Dns
  private val cacheFs = FakeFileSystem()
  private val eventRecorder = EventRecorder()
  private val bootstrapClient =
    OkHttpClient
      .Builder()
      .protocols(listOf(Protocol.HTTP_2, Protocol.HTTP_1_1))

    .url("https://dns.google/dns-query".toHttpUrl())
    .bootstrapDnsHosts(InetAddress.getByName("8.8.4.4"), InetAddress.getByName("8.8.8.8"))
    .build()

  val client = bootstrapClient.newBuilder().dns(dns).build()
```

 * configure the factory when sample values impact the correctness of the test.
 */
class TestValueFactory : Closeable {
  var taskFaker: TaskFaker = TaskFaker()
  var taskRunner: TaskRunner = taskFaker.taskRunner
  var dns: Dns = Dns.SYSTEM
  var proxy: Proxy = Proxy.NO_PROXY
  var proxySelector: ProxySelector = RecordingProxySelector()
  var proxyAuthenticator: Authenticator = RecordingOkAuthenticator("password", null)

        .newBuilder()
        .dns {
          Dns.SYSTEM.lookup("sni.cloudflaressl.com")
        }.build()

    val request =
      Request
        .Builder()
        .url("https://cloudflare-dns.com/cdn-cgi/trace")
        .build()
    client.newCall(request).execute().use { response ->
      assertThat(response.code).isEqualTo(200)
      assertThat(response.protocol).isEqualTo(Protocol.HTTP_2)

    return copy(writeTimeoutMillis = checkDuration("writeTimeout", timeout.toLong(), unit))
  }

  override fun withDns(dns: Dns): Interceptor.Chain {
    check(exchange == null) { "dns can't be adjusted in a network interceptor" }

    return copy(dns = dns)
  }

  override fun withSocketFactory(socketFactory: SocketFactory): Interceptor.Chain {

  @BeforeEach
  fun setUp() {
    socketFactory = SpecificHostSocketFactory(InetSocketAddress(server1.hostName, server1.port))

    client =
      clientTestRule
        .newClientBuilder()
        .dns(dns)
        .socketFactory(socketFactory)
        .eventListenerFactory(clientTestRule.wrap(eventRecorder))
        .build()
  }

  @RepeatedTest(100)
  fun http2OneBadHostOneGoodNoRetryOnConnectionFailure() {

      ),
    )
    server.enqueue(MockResponse())
    val dns = FakeDns()
    dns["fakeurl"] = client.dns.lookup(server.hostName)
    dns["www.fakeurl"] = client.dns.lookup(server.hostName)
    client =
      client
        .newBuilder()
        .dns(dns)
        .build()
    val call =
      client.newCall(
        Request
          .Builder()

///

### DNS { #dns }

Теперь сфокусируемся на собственно частях, связанных с HTTPS.

Сначала браузер спросит у **DNS‑серверов**, какой **IP соответствует домену**, в нашем примере `someapp.example.com`.

DNS‑серверы ответят браузеру, какой **конкретный IP‑адрес** использовать. Это будет публичный IP‑адрес вашего сервера, который вы указали в настройках DNS.

    object DnsOverride : Override<Dns> {
      override fun Interceptor.Chain.value(): Dns = dns

      override fun Interceptor.Chain.withOverride(value: Dns): Interceptor.Chain = withDns(value)

      override fun OkHttpClient.Builder.withOverride(value: Dns): OkHttpClient.Builder = dns(value)

      override val nonDefaultValue: Dns = Dns { Dns.SYSTEM.lookup(it) }

...
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseHeadersEnd: Response{protocol=h2, code=200, message=, url=https://1.1.1.1/dns-query?dns=AAABAAABAAAAAAAAA3d3dwhmYWNlYm9vawNjb20AABwAAQ}
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseBodyStart
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseBodyEnd: byteCount=128