OkHttp 4.x Change Log
=====================

## Version 4.12.0

_2023-10-16_

 *  Fix: Don't hang taking headers for HTTP 103 responses.

 *  Fix: Recover gracefully when a cache entry's certificate is corrupted.

 *  Fix: Fail permanently when there's a failure loading the bundled public suffix database.
    This is the dataset that powers `HttpUrl.topPrivateDomain()`.

    expectedEvents += "ConnectionReleased"
    expectedEvents += "CallEnd"
    assertThat(listener.recordedEventTypes()).isEqualTo(expectedEvents)

    // Confirm that the connection pool was not corrupted by making another call.
    makeSimpleCall()
  }

  /**
   * If the server returns a full response, it doesn't really matter if the HTTP/2 stream is reset.
   * Attempts to write the request body fails fast.
   */

Events
======

Events allow you to capture metrics on your application’s HTTP calls. Use events to monitor:

 * The size and frequency of the HTTP calls your application makes. If you’re making too many calls, or your calls are too large, you should know about it!
 * The performance of these calls on the underlying network. If the network’s performance isn’t sufficient, you need to either improve the network or use less of it.

### EventListener

### Holding multiple locks

You're allowed to take the Http2Connection lock while holding the Http2Writer lock. But not vice-versa. Because taking the Http2Writer lock can block.

    defaultSupportedCipherSuites =
      handshakeCertificates.sslSocketFactory().supportedCipherSuites.toList()
  }

  @Test
  fun testDefaultHandshakeCipherSuiteOrderingTls12Restricted() {
    // We are avoiding making guarantees on ordering of secondary Platforms.
    platform.assumeNotConscrypt()
    platform.assumeNotBouncyCastle()

    val client = makeClient(ConnectionSpec.RESTRICTED_TLS, TlsVersion.TLS_1_2)

 * point before or during the second request. It may be closed after client has started sending the
 * request body. If a request body is not retryable then the client may fail the request, making
 * client behavior non-deterministic. Add delays in the client to improve the chances that the
 * server has closed the socket before follow up requests are made.
 */
@ExperimentalOkHttpApi
sealed interface SocketPolicy {

      verifyHostname(hostname, it)
    }
  }

  /**
   * This is like [toLowerCase] except that it does nothing if this contains any non-ASCII
   * characters. We want to avoid lower casing special chars like U+212A (Kelvin symbol) because
   * they can return ASCII characters that match real hostnames.
   */
  private fun String.asciiToLowercase(): String {
    return when {

 * simplifies use of single-valued fields whose values routinely contain commas, such as cookies or
 * dates.
 *
 * This class trims whitespace from values. It never returns values with leading or trailing
 * whitespace.
 *
 * Instances of this class are immutable. Use [Builder] to create instances.
 */
@Suppress("NAME_SHADOWING")
class Headers internal constructor(

In limited situations OkHttp will retry a route if connecting fails:

 * When making an HTTPS connection through an HTTP proxy, the proxy may issue an authentication challenge. OkHttp will call the proxy [authenticator](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-authenticator/) and try again.

  /** Returns the original request that initiated this call. */
  fun request(): Request

  /**
   * Invokes the request immediately, and blocks until the response can be processed or is in error.
   *
   * To avoid leaking resources callers should close the [Response] which in turn will close the
   * underlying [ResponseBody].
   *
   * ```java
   * // ensure the response (and underlying response body) is closed