* should give up.
 *
 * When reactive authentication is requested by an origin web server, the response code is 401
 * and the implementation should respond with a new request that sets the "Authorization" header.
 *
 * ```java
 * if (response.request().header("Authorization") != null) {
 *   return null; // Give up, we've already failed to authenticate.
 * }
 *
 * String credential = Credentials.basic(...)

    testDecodeOnly(
      unicode = "ليهمابتكلموشعربي؟",
      punycode = "Xn--EgBpDaJ6Bu4bXfGeHfVwXn",
    )
  }

  /**
   * It's invalid to have a label longer than 63 characters. If that's requested, the encoder may
   * overflow and return null.
   */
  @Test fun overflowEncodingOversizedLabel() {
    val a1000 = "a".repeat(1000)
    val a1000MaxCodePoint = a1000 + "\udbff\udfff"
    testEncodeDecode(

        sourcePos += bytesToRead
        return bytesToRead
      }

      // Read from upstream. This always reads a full buffer: that might be more than what the
      // current call to Source.read() has requested.
      try {
        val upstreamBytesRead = upstream!!.read(upstreamBuffer, bufferMaxSize)

        // If we've exhausted upstream, we're done.
        if (upstreamBytesRead == -1L) {
          commit(upstreamPos)

  /** Sets the [real] address for [requested].  */
  operator fun set(
    requested: InetAddress,
    real: InetSocketAddress,
  ) {
    hostMapping[requested] = real
  }

  override fun createSocket(): Socket {
    return object : Socket() {
      override fun connect(
        endpoint: SocketAddress?,
        timeout: Int,
      ) {
        val requested = (endpoint as InetSocketAddress)

  val bodySize: Long,
  /** The body of this POST request. This may be truncated. */
  val body: Buffer,
  /**
   * The index of this request on its HTTP connection. Since a single HTTP connection may serve
   * multiple requests, each request is assigned its own sequence number.
   */
  val sequenceNumber: Int,
  socket: Socket,
  /**

  // Selects TLSv1.3 so we are specific about our intended version ranges (not just 1.3)
  // and because it's a common pattern for VMs to have differences between supported and
  // defaulted versions for TLS based on what is requested.
  override fun newSSLContext(): SSLContext = SSLContext.getInstance("TLSv1.3", provider)

  override fun platformTrustManager(): X509TrustManager {
    val factory =
      TrustManagerFactory.getInstance(

              println("Requested " + sslSocket.sslParameters.applicationProtocols.joinToString())
              println("Negotiated " + sslSocket.applicationProtocol)
            }
          },
        )
        .build()

    val request =
      Request.Builder()
        .url("https://www.google.com")
        .build()
    client.newCall(request).execute().use { response ->

    immutable = immutable,
    headerValue = headerValue,
  )
}

/**
 * Returns the next index in this at or after [startIndex] that is a character from
 * [characters]. Returns the input length if none of the requested characters can be found.
 */
private fun String.indexOfElement(
  characters: String,
  startIndex: Int = 0,
): Int {
  for (i in startIndex until length) {
    if (this[i] in characters) {
      return i

The response answers the request with a code (like 200 for success or 404 for not found), headers, and its own optional body.

## Rewriting Requests

When you provide OkHttp with an HTTP request, you’re describing the request at a high-level: _“fetch me this URL with these headers.”_ For correctness and efficiency, OkHttp rewrites your request before transmitting it.

  // Optional: confirm that your app made the HTTP requests you were expecting.
  RecordedRequest request1 = server.takeRequest();
  assertEquals("/v1/chat/messages/", request1.getPath());
  assertNotNull(request1.getHeader("Authorization"));

  RecordedRequest request2 = server.takeRequest();
  assertEquals("/v1/chat/messages/2", request2.getPath());

  RecordedRequest request3 = server.takeRequest();