• 设为首页
  • 点击收藏
  • 手机版
    手机扫一扫访问
    迪恩网络手机版
  • 关注官方公众号
    微信扫一扫关注
    迪恩网络公众号

fabric8io/kubernetes-client: Java client for Kubernetes & OpenShift

原作者: [db:作者] 来自: 网络 收藏 邀请

开源软件名称:

fabric8io/kubernetes-client

开源软件地址:

https://github.com/fabric8io/kubernetes-client

开源编程语言:

Java 98.2%

开源软件介绍:

Kubernetes & OpenShift Java Client Join the chat at https://gitter.im/fabric8io/kubernetes-client

This client provides access to the full Kubernetes & OpenShift REST APIs via a fluent DSL.

Build Sonar Scanner Bugs E2E Tests Release Twitter

Module Maven Central Javadoc
kubernetes-client Maven Central Javadocs
openshift-client Maven Central Javadocs
Extensions Maven Central Javadoc
knative-client Maven Central Javadocs
tekton-client Maven Central Javadocs
servicecatalog-client Maven Central Javadocs
chaosmesh-client Maven Central Javadocs
volumesnapshot-client Maven Central Javadocs
volcano-client Maven Central Javadocs
istio-client Maven Central Javadocs
open-cluster-management-client Maven Central Javadocs

Contents

Usage

Creating a client

The easiest way to create a client is:

KubernetesClient client = new KubernetesClientBuilder().build();

DefaultOpenShiftClient implements both the KubernetesClient & OpenShiftClient interface so if you need the OpenShift extensions, such as Builds, etc then simply do:

OpenShiftClient osClient = new KubernetesClientBuilder().build().adapt(OpenShiftClient.class);

Configuring the client

This will use settings from different sources in the following order of priority:

  • System properties
  • Environment variables
  • Kube config file
  • Service account token & mounted CA certificate

System properties are preferred over environment variables. The following system properties & environment variables can be used for configuration:

Property / Environment Variable Description Default value
kubernetes.disable.autoConfig / KUBERNETES_DISABLE_AUTOCONFIG Disable automatic configuration false
kubernetes.master / KUBERNETES_MASTER Kubernetes master URL https://kubernetes.default.svc
kubernetes.api.version / KUBERNETES_API_VERSION API version v1
openshift.url / OPENSHIFT_URL OpenShift master URL Kubernetes master URL value
kubernetes.oapi.version / KUBERNETES_OAPI_VERSION OpenShift API version v1
kubernetes.trust.certificates / KUBERNETES_TRUST_CERTIFICATES Trust all certificates false
kubernetes.disable.hostname.verification / KUBERNETES_DISABLE_HOSTNAME_VERIFICATION false
kubernetes.certs.ca.file / KUBERNETES_CERTS_CA_FILE
kubernetes.certs.ca.data / KUBERNETES_CERTS_CA_DATA
kubernetes.certs.client.file / KUBERNETES_CERTS_CLIENT_FILE
kubernetes.certs.client.data / KUBERNETES_CERTS_CLIENT_DATA
kubernetes.certs.client.key.file / KUBERNETES_CERTS_CLIENT_KEY_FILE
kubernetes.certs.client.key.data / KUBERNETES_CERTS_CLIENT_KEY_DATA
kubernetes.certs.client.key.algo / KUBERNETES_CERTS_CLIENT_KEY_ALGO Client key encryption algorithm RSA
kubernetes.certs.client.key.passphrase / KUBERNETES_CERTS_CLIENT_KEY_PASSPHRASE
kubernetes.auth.basic.username / KUBERNETES_AUTH_BASIC_USERNAME
kubernetes.auth.basic.password / KUBERNETES_AUTH_BASIC_PASSWORD
kubernetes.auth.serviceAccount.token / KUBERNETES_AUTH_SERVICEACCOUNT_TOKEN Name of the service account token file /var/run/secrets/kubernetes.io/serviceaccount/token
kubernetes.auth.tryKubeConfig / KUBERNETES_AUTH_TRYKUBECONFIG Configure client using Kubernetes config true
kubeconfig / KUBECONFIG Name of the kubernetes config file to read ~/.kube/config
kubernetes.auth.tryServiceAccount / KUBERNETES_AUTH_TRYSERVICEACCOUNT Configure client from Service account true
kubernetes.tryNamespacePath / KUBERNETES_TRYNAMESPACEPATH Configure client namespace from Kubernetes service account namespace path true
kubernetes.auth.token / KUBERNETES_AUTH_TOKEN
kubernetes.watch.reconnectInterval / KUBERNETES_WATCH_RECONNECTINTERVAL Watch reconnect interval in ms 1000
kubernetes.watch.reconnectLimit / KUBERNETES_WATCH_RECONNECTLIMIT Number of reconnect attempts (-1 for infinite) -1
kubernetes.connection.timeout / KUBERNETES_CONNECTION_TIMEOUT Connection timeout in ms (0 for no timeout) 10000
kubernetes.request.timeout / KUBERNETES_REQUEST_TIMEOUT Read timeout in ms 10000
kubernetes.upload.connection.timeout / KUBERNETES_UPLOAD_CONNECTION_TIMEOUT Pod upload connection timeout in ms 10000
kubernetes.upload.request.timeout / KUBERNETES_UPLOAD_REQUEST_TIMEOUT Pod upload request timeout in ms 120000
kubernetes.request.retry.backoffLimit / KUBERNETES_REQUEST_RETRY_BACKOFFLIMIT Number of retry attempts 0
kubernetes.request.retry.backoffInterval / KUBERNETES_REQUEST_RETRY_BACKOFFINTERVAL Retry initial backoff interval in ms 1000
kubernetes.rolling.timeout / KUBERNETES_ROLLING_TIMEOUT Rolling timeout in ms 900000
kubernetes.logging.interval / KUBERNETES_LOGGING_INTERVAL Logging interval in ms 20000
kubernetes.scale.timeout / KUBERNETES_SCALE_TIMEOUT Scale timeout in ms 600000
kubernetes.websocket.timeout / KUBERNETES_WEBSOCKET_TIMEOUT Websocket timeout in ms 5000
kubernetes.websocket.ping.interval / kubernetes_websocket_ping_interval Websocket ping interval in ms 30000
kubernetes.max.concurrent.requests / KUBERNETES_MAX_CONCURRENT_REQUESTS 64
kubernetes.max.concurrent.requests.per.host / KUBERNETES_MAX_CONCURRENT_REQUESTS_PER_HOST 5
kubernetes.impersonate.username / KUBERNETES_IMPERSONATE_USERNAME Impersonate-User HTTP header value
kubernetes.impersonate.group / KUBERNETES_IMPERSONATE_GROUP Impersonate-Group HTTP header value
kubernetes.tls.versions / KUBERNETES_TLS_VERSIONS TLS versions separated by , TLSv1.2
kubernetes.truststore.file / KUBERNETES_TRUSTSTORE_FILE
kubernetes.truststore.passphrase / KUBERNETES_TRUSTSTORE_PASSPHRASE
kubernetes.keystore.file / KUBERNETES_KEYSTORE_FILE
kubernetes.keystore.passphrase / KUBERNETES_KEYSTORE_PASSPHRASE
kubernetes.backwardsCompatibilityInterceptor.disable / KUBERNETES_BACKWARDSCOMPATIBILITYINTERCEPTOR_DISABLE Disable BackwardsCompatibilityInterceptor true

Alternatively you can use the ConfigBuilder to create a config object for the Kubernetes client:

Config config = new ConfigBuilder().withMasterUrl("https://mymaster.com").build();
KubernetesClient client = new KubernetesClientBuilder().withConfig(config).build();

Using the DSL is the same for all resources.

List resources:

NamespaceList myNs = client.namespaces().list();

ServiceList myServices = client.services().list();

ServiceList myNsServices = client.services().inNamespace("default").list();

Get a resource:

Namespace myns = client.namespaces().withName("myns").get();

Service myservice = client.services().inNamespace("default").withName("myservice").get();

Delete:

Namespace myns = client.namespaces().withName("myns").delete();

Service myservice = client.services().inNamespace("default").withName("myservice").delete();

Editing resources uses the inline builders from the Kubernetes Model:

Namespace myns = client.namespaces().withName("myns").edit(n -> new NamespaceBuilder(n)
                   .editMetadata()
                     .addToLabels("a", "label")
                   .endMetadata()
                   .build());

Service myservice = client.services().inNamespace("default").withName("myservice").edit(s -> new ServiceBuilder(s)
                     .editMetadata()
                       .addToLabels("another", "label")
                     .endMetadata()
                     .build());

In the same spirit you can inline builders to create:

Namespace myns = client.namespaces().create(new NamespaceBuilder()
                   .withNewMetadata()
                     .withName("myns")
                     .addToLabels("a", "label")
                   .endMetadata()
                   .build());

Service myservice = client.services().inNamespace("default").create(new ServiceBuilder()
                     .withNewMetadata()
                       .withName("myservice")
                       .addToLabels("another", "label")
                     .endMetadata()
                     .build());

You can also set the apiVersion of the resource like in the case of SecurityContextConstraints :

SecurityContextConstraints scc = new SecurityContextConstraintsBuilder()
		.withApiVersion("v1")
		.withNewMetadata().withName("scc").endMetadata()
		.withAllowPrivilegedContainer(true)
		.withNewRunAsUser()
		.withType("RunAsAny")
		.endRunAsUser()
		.build();

Following events

Use io.fabric8.kubernetes.api.model.Event as T for Watcher:

client.events().inAnyNamespace().watch(new Watcher<Event>() {

  @Override
  public void eventReceived(Action action, Event resource) {
    System.out.println("event " + action.name() + " " + resource.toString());
  }

  @Override
  public void onClose(KubernetesClientException cause) {
    System.out.println("Watcher close due to " + cause);
  }

});

Working with extensions

The kubernetes API defines a bunch of extensions like daemonSets, jobs, ingresses and so forth which are all usable in the extensions() DSL:

e.g. to list the jobs...

jobs = client.batch().jobs().list();

Loading resources from external sources

There are cases where you want to read a resource from an external source, rather than defining it using the clients DSL. For those cases the client allows you to load the resource from:

  • A file (Supports both java.io.File and java.lang.String)
  • A url
  • An input stream

Once the resource is loaded, you can treat it as you would, had you created it yourself.

For example lets read a pod, from a yml file and work with it:

Pod refreshed = client.load('/path/to/a/pod.yml').fromServer().get();
client.load('/workspace/pod.yml').delete();
LogWatch handle = client.load('/workspace/pod.yml').watchLog(System.out);

Passing a reference of a resource to the client

In the same spirit you can use an object created externally (either a reference or using its string representation).

For example:

Pod pod = someThirdPartyCodeThatCreatesAPod();
client.resource(pod).delete();

Adapting the client

The client supports plug-able adapters. An example adapter is the OpenShift Adapter which allows adapting an existing KubernetesClient instance to an OpenShiftClient one.

For example:

KubernetesClient client = new KubernetesClientBuilder().build();

OpenShiftClient oClient = client.adapt(OpenShiftClient.class);

The client also support the isAdaptable() method which checks if the adaptation is possible and returns true if it does.

KubernetesClient client = new KubernetesClientBuilder().build();
if (client.isAdaptable(OpenShiftClient.class)) {
    OpenShiftClient oClient = client.adapt(OpenShiftClient.class);
} else {
    throw new Exception("Adapting to OpenShiftClient not support. Check if adapter is present, and that env provides /oapi root path.");
}

Adapting and close

Note that when using adapt() both the adaptee and the target will share the same resources (underlying http client, thread pools etc). This means that close() is not required to be used on every single instance created via adapt. Calling close() on any of the adapt() managed instances or the original instance, will properly clean up all the resources and thus none of the instances will be usable any longer.

Mocking Kubernetes

Along with the client this project also provides a kubernetes mock server that you can use for testing purposes. The mock server is based on https://github.com/square/okhttp/tree/master/mockwebserver but is empowered by the DSL and features provided by https://github.com/fabric8io/mockwebserver.

The Mock Web Server has two modes of operation:

  • Expectations mode
  • CRUD mode

Expectations mode

It's the typical mode where you first set which are the expected http requests and which should be the responses for each request. More details on usage can be found at: https://github.com/fabric8io/mockwebserver

This mode has been extensively used for testing the client itself. Make sure you check kubernetes-test.

To add a Kubernetes server to your test:

@Rule
public KubernetesServer server = new KubernetesServer();

CRUD mode

Defining every single request and response can become tiresome. Given that in most cases the mock webserver is used to perform simple crud based operations, a crud mode has been added. When using the crud mode, the mock web server will store, read, update and delete kubernetes resources using an in memory map and will appear as a real api server.

To add a Kubernetes Server in crud mode to your test:

@Rule
public KubernetesServer server = new KubernetesServer(true, true);

Then you can use the server like:

@Test
public void testInCrudMode() {
    KubernetesClient client = server.getClient();
    final CountDownLatch deleteLatch = new CountDownLatch(1);
    final CountDownLatch closeLatch = new CountDownLatch(1);

    //CREATE
    client.pods().inNamespace("ns1").create(new PodBuilder().withNewMetadata().withName("pod1").endMetadata().build());

    //READ
    podList = client.pods().inNamespace("ns1").list();
    assertNotNull(podList);
    assertEquals(1, podList.getItems().size());

    //WATCH
    Watch watch = client.pods().inNamespace("ns1").withName("pod1").watch(new Watcher<Pod>() {
        @Override
        public void eventReceived(Action action, Pod resource) {
            switch (action) {
                case DELETED:
                    deleteLatch.countDown();
                    break;
                default:
                    throw new AssertionFailedError(action.toString().concat(" isn't recognised."));
            }
        }

        @Override
        public void onClose(KubernetesClientException cause) {
            closeLatch.countDown();
        }
    });

    //DELETE
    client.pods().inNamespace("ns1").withName("pod1").delete();

    //READ AGAIN
    podList = client.pods().inNamespace("ns1").list();
    assertNotNull(podList);
    assertEquals(0, podList.getItems().size());

    assertTrue(deleteLatch.await(1, TimeUnit.MINUTES));
    watch.close();
    assertTrue(closeLatch.await(1, TimeUnit.MINUTES));
}

JUnit5 support through extension

You can use KubernetesClient mocking mechanism with JUnit5. Since it doesn't support @Rule and @ClassRule there is dedicated annotation @EnableKubernetesMockClient. If you would like to create instance of mocked KubernetesClient for each test (JUnit4 @Rule) you need to declare instance of KubernetesClient as shown below.

@EnableKubernetesMockClient
class ExampleTest {

    KubernetesClient client;

    @Test
    public void testInStandardMode() {
            ...
    }
}

In case you would like to define static instance of mocked server per all the test (JUnit4 @ClassRule) you need to declare instance of KubernetesClient as shown below. You can also enable crudMode by using annotation field crud.

@EnableKubernetesMockClient(crud = true)
class ExampleTest {

    static KubernetesClient client;

    @Test
    public void testInCrudMode() {
            ...
    }
}

Compatibility Matrix


鲜花

握手

雷人

路过

鸡蛋
该文章已有0人参与评论

请发表评论

全部评论

专题导读
上一篇:
dromara/hutool: 发布时间:2022-06-22
下一篇:
Vedenin/useful-java-links: A list of useful Java frameworks, libraries, software ...发布时间:2022-06-22
热门推荐
阅读排行榜

扫描微信二维码

查看手机版网站

随时了解更新最新资讯

139-2527-9053

在线客服(服务时间 9:00~18:00)

在线QQ客服
地址:深圳市南山区西丽大学城创智工业园
电邮:jeky_zhao#qq.com
移动电话:139-2527-9053

Powered by 互联科技 X3.4© 2001-2213 极客世界.|Sitemap