}

      val isUpgradeResponse =
        isUpgradeCode &&
          "upgrade".equals(response.header("Connection"), ignoreCase = true)

      response =
        when {
          // This is an HTTP/1 upgrade. (This case includes web socket upgrades.)
          isUpgradeRequest && isUpgradeResponse -> {
            response
              .newBuilder()
              .body(

  }

  @Test
  fun upgradeHttps() {
    enableTls(Protocol.HTTP_1_1)
    upgrade()
  }

  @Test
  fun upgradeRefusedByServer() {
    server.enqueue(MockResponse(body = "normal request"))
    val requestWithUpgrade =
      Request
        .Builder()
        .url(server.url("/"))
        .header("Connection", "upgrade")
        .build()
    client.newCall(requestWithUpgrade).execute().use { response ->

* `upgrade`: Upgrades

   [Gradle plugin][japicmp_gradle] to enforce binary compatibility.

 * **Java source compatibility** is the ability to upgrade Java uses of OkHttp 3.x to 4.x without
   changing `.java` files.

 * **Kotlin source compatibility** is the ability to upgrade Kotlin uses of OkHttp 3.x to 4.x
   without changing `.kt` files.

With a few small exceptions (below), OkHttp 4.x is both binary- and Java source-compatible with

        Mockito.verify(context.logger)
                .info(
                        "  -a, --all             Apply all upgrades (equivalent to --model-version 4.1.0 --infer --model --plugins)");
    }

    @Test
    void testHelpIncludesDefaultBehavior() throws Exception {
        UpgradeContext context = createMockContext();

        help.execute(context);

    - [Node Binaries](#node-binaries-15)
    - [Container Images](#container-images-15)
  - [Changelog since v1.27.0](#changelog-since-v1270)
  - [Urgent Upgrade Notes](#urgent-upgrade-notes)
    - [(No, really, you MUST read this before you upgrade)](#no-really-you-must-read-this-before-you-upgrade)
  - [Changes by Kind](#changes-by-kind-15)
    - [Deprecation](#deprecation)
    - [API Change](#api-change-4)
    - [Feature](#feature-12)

    coders call this and we don't want their users to suffer.


## Version 4.0.0

_2019-06-26_

**This release upgrades OkHttp to Kotlin.** We tried our best to make fast and safe to upgrade
from OkHttp 3.x. We wrote an [upgrade guide][upgrading_to_okhttp_4] to help with the migration and a
[blog post][okhttp4_blog_post] to explain it.

 *  Fix: Target Java 8 bytecode for Java and Kotlin.

    - [Node Binaries](#node-binaries-15)
    - [Container Images](#container-images-15)
  - [Changelog since v1.25.0](#changelog-since-v1250)
  - [Urgent Upgrade Notes](#urgent-upgrade-notes)
    - [(No, really, you MUST read this before you upgrade)](#no-really-you-must-read-this-before-you-upgrade)
  - [Changes by Kind](#changes-by-kind-15)
    - [Deprecation](#deprecation)
    - [API Change](#api-change-8)
    - [Feature](#feature-15)

* Implemented `kubeadm upgrade plan` for checking whether you can upgrade your cluster to a newer version ([#48899](https://github.com/kubernetes/kubernetes/pull/48899), [@luxas](https://github.com/luxas))
    * Implemented `kubeadm upgrade apply` for upgrading your cluster from one version to an other

    - [Node Binaries](#node-binaries-7)
    - [Container Images](#container-images-7)
  - [Changelog since v1.32.0](#changelog-since-v1320)
  - [Urgent Upgrade Notes](#urgent-upgrade-notes)
    - [(No, really, you MUST read this before you upgrade)](#no-really-you-must-read-this-before-you-upgrade)
  - [Changes by Kind](#changes-by-kind-7)
    - [Deprecation](#deprecation)
    - [API Change](#api-change-1)
    - [Feature](#feature-5)