first connect fails. This is necessary for IPv4+IPv6 and services hosted in redundant data
centers. OkHttp supports modern TLS features (TLS 1.3, ALPN, certificate pinning). It can be
configured to fall back for broad connectivity.

Using OkHttp is easy. Its request/response API is designed with fluent builders and immutability. It
supports both synchronous blocking calls and async calls with callbacks.


Get a URL

        .build(),
    )
    val call =
      client.newCall(
        Request.Builder()
          .url(server.url("/"))
          .build(),
      )
    call.enqueue(
      object : Callback {
        override fun onFailure(
          call: Call,
          e: IOException,
        ) {
        }

        override fun onResponse(
          call: Call,
          response: Response,
        ) {

    runTest {
      val call = ClosableCall()

      supervisorScope {
        assertFailsWith<CancellationException> {
          coroutineScope {
            call.afterCallbackOnResponse = {
              coroutineContext.job.cancel()
            }
            call.executeAsync()
          }
        }
      }

      assertThat(call.canceled).isTrue()

        .build();

    final long startNanos = System.nanoTime();
    final Call call = client.newCall(request);

    // Schedule a job to cancel the call in 1 second.
    executor.schedule(() -> {
      System.out.printf("%.2f Canceling call.%n", (System.nanoTime() - startNanos) / 1e9f);
      call.cancel();
      System.out.printf("%.2f Canceled call.%n", (System.nanoTime() - startNanos) / 1e9f);
    }, 1, TimeUnit.SECONDS);

  @ValueSource(booleans = [true, false])
  fun successfulCallEventSequence() {
    server!!.enqueue(MockResponse(body = "abc"))
    val call =
      client.newCall(
        Request.Builder()
          .url(server!!.url("/"))
          .build(),
      )
    val response = call.execute()
    assertThat(response.code).isEqualTo(200)
    assertThat(response.body.string()).isEqualTo("abc")
    response.body.close()

        override fun requestHeadersEnd(
          call: Call,
          request: Request,
        ) = TODO()

        override fun requestBodyStart(call: Call) = TODO()

        override fun requestBodyEnd(
          call: Call,
          byteCount: Long,
        ) = TODO()

        override fun requestFailed(
          call: Call,
          ioe: IOException,

        .build()

    client.newCall(request).enqueue(
      object : Callback {
        override fun onFailure(
          call: Call,
          e: IOException,
        ) {
          e.printStackTrace()
        }

        override fun onResponse(
          call: Call,
          response: Response,
        ) {
          response.use {

              .supportsTlsExtensions(false)
              .build(),
          ),
        )
        .eventListener(
          object : EventListener() {
            override fun connectionAcquired(
              call: Call,
              connection: Connection,
            ) {
              val sslSocket = connection.socket() as SSLSocket
              println("Requested " + sslSocket.sslParameters.applicationProtocols.joinToString())

    server.enqueue(MockResponse(body = "abc"))
    server.enqueue(MockResponse(body = "def"))

    val request = Request(server.url("/"))

    val call = client.newCall(request)
    val response1 = call.execute()

    val cloned = call.clone()
    val response2 = cloned.execute()

    assertThat("abc").isEqualTo(response1.body.string())
    assertThat("def").isEqualTo(response2.body.string())
  }

    val request = Request.Builder().url(url).build()
    val call = client.newCall(request)
    val response =
      Response.Builder().request(request).code(200).message("").protocol(Protocol.HTTP_2)
        .build()
    val listener = loggingEventListenerFactory.create(call)
    listener.cacheConditionalHit(call, response)
    listener.cacheHit(call, response)
    listener.cacheMiss(call)
    listener.satisfactionFailure(call, response)