route: Route?,
    response: Response,
  ): Request? {
    val challenges = response.challenges()
    val request = response.request
    val url = request.url
    val proxyAuthorization = response.code == 407
    val proxy = route?.proxy ?: Proxy.NO_PROXY

    for (challenge in challenges) {
      if (!"Basic".equals(challenge.scheme, ignoreCase = true)) {
        continue
      }

            return null; // Give up, we've already attempted to authenticate.
          }

          System.out.println("Authenticating for response: " + response);
          System.out.println("Challenges: " + response.challenges());
          String credential = Credentials.basic("jesse", "password1");
          return response.request().newBuilder()
              .header("Authorization", credential)
              .build();
        })

 */
fun Headers.parseChallenges(headerName: String): List<Challenge> {
  val result = mutableListOf<Challenge>()
  for (h in 0 until size) {
    if (headerName.equals(name(h), ignoreCase = true)) {
      val header = Buffer().writeUtf8(value(h))
      try {
        header.readChallengeHeader(result)
      } catch (e: EOFException) {
        Platform.get().log("Unable to parse challenge", Platform.WARN, e)
      }
    }
  }

              return null // Give up, we've already attempted to authenticate.
            }

            println("Authenticating for response: $response")
            println("Challenges: ${response.challenges()}")
            val credential = Credentials.basic("jesse", "password1")
            return response.request.newBuilder()
              .header("Authorization", credential)
              .build()
          }

    return response.request.newBuilder()
      .addHeader(header, credential)
      .build()
  }

  private fun schemeMatches(response: Response): Boolean {
    if (scheme == null) return true
    return response.challenges().any { it.scheme.equals(scheme, ignoreCase = true) }
  }

 * connection is typically faster than establishing a new one.
 *
 * When a single logical call requires multiple streams due to redirects or authorization
 * challenges, we prefer to use the same physical connection for all streams in the sequence. There
 * are potential performance and behavior consequences to this preference. To support this feature,

 4. If it's a new route, it connects by building either a direct socket connection, a TLS tunnel (for HTTPS over an HTTP proxy), or a direct TLS connection. It does TLS handshakes as necessary. This step may be retried for tunnel challenges and TLS handshake failures.
 5. It sends the HTTP request and reads the response.

 * challenge. The proxy authenticator may return either an authenticated request, or null to
 * connect without authentication.
 *
 * ```java
 * for (Challenge challenge : response.challenges()) {
 *   // If this is preemptive auth, use a preemptive credential.
 *   if (challenge.scheme().equalsIgnoreCase("OkHttp-Preemptive")) {

A single HTTP call may require follow-up requests to be made to handle authentication challenges, redirects, and HTTP-layer timeouts. In such cases multiple connections, requests, and responses may be attempted. Follow-ups are another reason a single call may trigger multiple events of the same type.

import okhttp3.internal.commonEquals
import okhttp3.internal.commonHashCode
import okhttp3.internal.commonToString

/**
 * An [RFC 7235][rfc_7235] challenge.
 *
 * [rfc_7235]: https://tools.ietf.org/html/rfc7235
 */
class Challenge(
  /** Returns the authentication scheme, like `Basic`. */
  @get:JvmName("scheme") val scheme: String,
  authParams: Map<String?, String>,
) {
  /**