private fun setLevel(level: Level) {
    networkInterceptor.setLevel(level)
    applicationInterceptor.setLevel(level)
  }

  @BeforeEach
  fun setUp(server: MockWebServer) {
    this.server = server
    client =
      OkHttpClient.Builder()
        .addNetworkInterceptor(
          Interceptor { chain ->
            when {

    socketFile.delete(); // Clean up from previous runs.

    MockWebServer server = new MockWebServer();
    server.setServerSocketFactory(new UnixDomainServerSocketFactory(socketFile));
    server.setProtocols(Collections.singletonList(Protocol.H2_PRIOR_KNOWLEDGE));
    server.enqueue(new MockResponse().setBody("hello"));
    server.start();

    OkHttpClient client = new OkHttpClient.Builder()

    private var started = false

    fun server(name: String): MockWebServer {
      return servers.getOrPut(name) {
        MockWebServer().also {
          if (started) it.start()
        }
      }
    }

    fun startAll() {
      started = true
      for (server in servers.values) {
        server.start()
      }
    }

    fun shutdownAll() {
      try {

    return InetSocketAddress(serverAddress, serverSocket!!.localPort)
  }

  private fun doServerHandshake(server: HandshakeCertificates): Future<Handshake> {
    return executorService.submit<Handshake> {
      serverSocket!!.accept().use { rawSocket ->
        val sslSocket =
          server.sslSocketFactory().createSocket(
            rawSocket,
            rawSocket.inetAddress.hostAddress,

  val expectedModernTls13CipherSuites = listOf(TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, TLS_AES_128_GCM_SHA256, TLS_AES_256_GCM_SHA384)

  @BeforeEach
  fun setup(server: MockWebServer) {
    this.server = server

    server.enqueue(MockResponse())

    client =
      clientTestRule.newClientBuilder()
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),

    const val HEADER_TABLE_SIZE = 1

    /** HTTP/2: The peer must not send a PUSH_PROMISE frame when this is 0. */
    const val ENABLE_PUSH = 2

    /** Sender's maximum number of concurrent streams. */
    const val MAX_CONCURRENT_STREAMS = 4

    /** HTTP/2: Size in bytes of the largest frame payload the sender will accept. */
    const val MAX_FRAME_SIZE = 5

   * received without TLS.
   */
  val handshake: Handshake?
  val requestUrl: HttpUrl?

  /**
   * Returns the name of the server the client requested via the SNI (Server Name Indication)
   * attribute in the TLS handshake. Unlike the rest of the HTTP exchange, this name is sent in
   * cleartext and may be monitored or blocked by a proxy or other middlebox.
   */

 * follow-up requests. The client is unblocked and free to continue as soon as it has received the
 * entire response body. If and when the client makes a subsequent request using a pooled socket the
 * server may not have had time to close the socket. The socket will be closed at an indeterminate
 * point before or during the second request. It may be closed after client has started sending the

So we have a dedicated thread for every socket that just reads frames and dispatches them.

The reader thread must never run application-layer code. Otherwise one slow stream can hold up the entire connection.

        )
    }
  }

  override fun cancel() {
    carrier.cancel()
  }

  /**
   * Prepares the HTTP headers and sends them to the server.
   *
   * For streaming requests with a body, headers must be prepared **before** the output stream has
   * been written to. Otherwise the body would need to be buffered!
   *