pings, but it did not track whether the reply pongs were received. With this
    update OkHttp requires that every ping receive a response: if it does not
    the connection will be closed and the listener's `onFailure()` method will
    be called.

    Web sockets have always been had pings, but pings on HTTP/2 connections is
    new in this release. Pings are used for connections that are busy carrying

     *
     * The default value of 0 disables client-initiated pings.
     */
    fun pingInterval(
      interval: Long,
      unit: TimeUnit,
    ) = apply {
      pingInterval = checkDuration("interval", interval, unit)
    }

    /**
     * Sets the interval between HTTP/2 and web socket pings initiated by this client. Use this to

O `secrets.compare_digest()` necessita receber `bytes` ou `str` que possuem apenas caracteres ASCII (os em inglês). Isso significa que não funcionaria com caracteres como o `á`, como em `Sebastián`.

Para lidar com isso, primeiramente nós convertemos o `username` e o `password` para `bytes`, codificando-os com UTF-8.

  private val settingsListenerQueue = taskRunner.newQueue()

  /** User code to run in response to push promise events. */
  private val pushObserver: PushObserver = builder.pushObserver

  // Total number of pings send and received of the corresponding types. All guarded by this.
  private var intervalPingsSent = 0L
  private var intervalPongsReceived = 0L
  private var degradedPingsSent = 0L
  private var degradedPongsReceived = 0L

    client.processNextFrame()
    taskFaker.runTasks()
    server.webSocket!!.pong("pong 3".encodeUtf8())
    client.processNextFrame()

    // After 500ms the client automatically pings and the server pongs back.
    taskFaker.advanceUntil(ns(500L))
    server.processNextFrame() // Ping.
    client.processNextFrame() // Pong.

///

Uma <a href="https://pt.wikipedia.org/wiki/Variável_de_ambiente" class="external-link" target="_blank">variável de ambiente</a> (abreviada em inglês para "env var") é uma variável definida fora do código Python, no sistema operacional, e pode ser lida pelo seu código Python (ou por outros programas).

  /**
   * The HTTP <a href="http://html.spec.whatwg.org/multipage/semantics.html#hyperlink-auditing">
   * {@code Ping-To}</a> header field name.
   *
   * @since 19.0
   */
  public static final String PING_TO = "Ping-To";

  /**
   * The HTTP <a
   * href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Link_prefetching_FAQ#As_a_server_admin.2C_can_I_distinguish_prefetch_requests_from_normal_requests.3F">{@code

## Version 4.3.0

_2019-12-31_

 *  Fix: Degrade HTTP/2 connections after a timeout. When an HTTP/2 stream times out it may impact
    the stream only or the entire connection. With this fix OkHttp will now send HTTP/2 pings after
    a stream timeout to determine whether the connection should remain eligible for pooling.

 *  Fix: Don't call `EventListener.responseHeadersStart()` or `responseBodyStart()` until bytes have

        .pingInterval(Duration.ofMillis(500))
        .build()

    // Set up the server to ignore the socket. It won't respond to pings!
    server.enqueue(MockResponse.Builder().onRequestStart(Stall).build())

    // Make a call. It'll fail as soon as our pings detect a problem.
    val call = client.newCall(Request(server.url("/")))
    val executeAtNanos = System.nanoTime()

// https://www.iana.org/domains/root/db/silk.html
silk

// sina : Sina Corporation
// https://www.iana.org/domains/root/db/sina.html
sina

// singles : Binky Moon, LLC
// https://www.iana.org/domains/root/db/singles.html
singles

// site : Radix Technologies Inc.
// https://www.iana.org/domains/root/db/site.html
site

// ski : Identity Digital Limited