1

しばらく前に尋ねたこの質問に対する実用的な解決策を得るために、fabric8 events() API を試してきました。

前述の質問に対する答えは、「events() API を使用してください!」でした。これは素晴らしいアイデアのように思えます...しかし、想像できる最も基本的な方法でさえそのAPIを使用しようとすると、奇妙なエラーが発生します。問題を説明する簡単なプログラムを (サンプル プログラムのセクションに) 含めました。以下は、最も関連性の高いコードの抜粋です。 

  val eventWatcher: Watcher[Event] = new Watcher[Event]() {
    def eventReceived(action: Action, event: Event) {
      logger.info("notified!")
    }
  }

   ... 
  kube = getConnection  // get client connection to k8s server
  kube.events().watch(eventWatcher)

イベント ウォッチを設定したら、ポッドを作成します。ポッドは問題なく作成されます。ただし、「eventReceived」コールバックが呼び出されると、以下の「エラー」にリストするエラーとスタック トレースが表示されます。eventReceived メソッドに入ることはありません (そして、文字列 'notified' がログに表示されることはありません)。

ヒント、提案、ガイダンス、大歓迎です！-クリス

サンプルプログラム

import com.fasterxml.jackson.databind.ObjectMapper
import scala.collection.JavaConverters._
import com.ning.http.client.ws.WebSocket
import com.typesafe.scalalogging.StrictLogging
import io.fabric8.kubernetes.api.model._
import io.fabric8.kubernetes.client.DefaultKubernetesClient.ConfigBuilder
import io.fabric8.kubernetes.client.Watcher.Action
import io.fabric8.kubernetes.client.dsl.Resource
import io.fabric8.kubernetes.client.{DefaultKubernetesClient, Watcher}

object ErrorTest extends App with StrictLogging {
  // corresponds to --insecure-skip-tls-verify=true, according to io.fabric8.kubernetes.api.model.Cluster
  val trustCerts = true
  val k8sUrl = "http://localhost:8080"
  val namespaceName = "default" // replace this with name of a namespace that you know exists
  val imageName: String = "nginx" //  make image name to load to pod a variable so we can experiment with err conditions

  val eventWatcher: Watcher[Event] = new Watcher[Event]() {
    def eventReceived(action: Action, event: Event) {
      logger.info("notified!")
    }
  }

  def go(): Unit = {
    val kube = getConnection
    dumpNamespaces(kube)
    kube.events().watch(eventWatcher)
    deployPodWithWatch(kube, getPod(image = imageName))
  }

  def deployPodWithWatch(kube: DefaultKubernetesClient, pod: Pod): Unit = {
    kube.pods().inNamespace(namespaceName).create(pod) /*  create the pod ! */
  }

  def getPod(image: String): Pod = {
    val jsonTemplate =
      """
    |{
    | "kind": "Pod",
    | "apiVersion": "v1",
    | "metadata": {
    |   "name": "podboy",
    |   "labels": {
    |     "app": "nginx"
    |   }
    | },
    | "spec": {
    |   "containers": [
    |     {
    |     "name": "podboy",
    |     "image": "<image>",
    |     "ports": [
    |       {
    |         "containerPort": 80,
    |         "protocol": "TCP"
    |       }
    |     ]
    |     }
    |   ]
    | }
    |}
      """.
    stripMargin
    val replacement: String = "image\": \"" + image
    val json = jsonTemplate.replaceAll("image\": \"<image>", replacement)
    System.out.println("json:" + json);
    new ObjectMapper().readValue(json, classOf[Pod])
  }

  def dumpNamespaces(kube: DefaultKubernetesClient): Unit = {
    val namespaceNames = kube.namespaces().list().getItems.asScala.map {
      (ns: Namespace) => {
    ns.getMetadata.getName
      }
    }
    System.out.println("namespaces are:" + namespaceNames);
  }

  def getConnection = {
    val configBuilder = new ConfigBuilder()
    val config =
      configBuilder.
    trustCerts(trustCerts).
    masterUrl(k8sUrl).
    build()
    new DefaultKubernetesClient(config)
  }

  go()
}

エラー

    22:03:16.656 [New I/O worker #2] ERROR i.f.k.c.dsl.internal.BaseOperation$3 - Could not deserialize watch event: {"type":"MODIFIED","object":{"kind":"Event","apiVersion":"v1","metadata":{"name":"spark-master-rc-zlxpp.144f898e0549644b","namespace":"dummyowner-workflow-dda91220-b63-1544803905","selfLink":"/api/v1/namespaces/dummyowner-workflow-dda91220-b63-1544803905/events/spark-master-rc-zlxpp.144f898e0549644b","resourceVersion":"204015294","creationTimestamp":null,"deletionTimestamp":"2016-05-18T06:03:06Z"},"involvedObject":{"kind":"Pod","namespace":"dummyowner-workflow-dda91220-b63-1544803905","name":"spark-master-rc-zlxpp","uid":"d413698c-19c7-11e6-9f26-74dbd1a09231","apiVersion":"v1","resourceVersion":"203578210","fieldPath":"spec.containers{spark-master}"},"reason":"Failed","message":"Failed to pull image \"ecr.vip.ebayc3.com/krylov/spark-1.5.1:${env}\": image pull failed for ecr.vip.ebayc3.com/krylov/spark-1.5.1:${env}, this may be because there are no credentials on this request.  details: (Tag ${env} not found in repository ecr.vip.ebayc3.com/krylov/spark-1.5.1)","source":{"component":"kubelet","host":"kubernetes-minion-105-4040.slc01.dev.ebayc3.com"},"firstTimestamp":"2016-05-18T02:47:26Z","lastTimestamp":"2016-05-18T05:03:05Z","count":815}}
    com.fasterxml.jackson.databind.JsonMappingException: No resource type found for kind:Event
     at [Source: {"type":"MODIFIED","object":{"kind":"Event","apiVersion":"v1","metadata":{"name":"spark-master-rc-zlxpp.144f898e0549644b","namespace":"dummyowner-workflow-dda91220-b63-1544803905","selfLink":"/api/v1/namespaces/dummyowner-workflow-dda91220-b63-1544803905/events/spark-master-rc-zlxpp.144f898e0549644b","resourceVersion":"204015294","creationTimestamp":null,"deletionTimestamp":"2016-05-18T06:03:06Z"},"involvedObject":{"kind":"Pod","namespace":"dummyowner-workflow-dda91220-b63-1544803905","name":"spark-master-rc-zlxpp","uid":"d413698c-19c7-11e6-9f26-74dbd1a09231","apiVersion":"v1","resourceVersion":"203578210","fieldPath":"spec.containers{spark-master}"},"reason":"Failed","message":"Failed to pull image \"ecr.vip.ebayc3.com/krylov/spark-1.5.1:${env}\": image pull failed for ecr.vip.ebayc3.com/krylov/spark-1.5.1:${env}, this may be because there are no credentials on this request.  details: (Tag ${env} not found in repository ecr.vip.ebayc3.com/krylov/spark-1.5.1)","source":{"component":"kubelet","host":"kubernetes-minion-105-4040.slc01.dev.ebayc3.com"},"firstTimestamp":"2016-05-18T02:47:26Z","lastTimestamp":"2016-05-18T05:03:05Z","count":815}}; line: 1, column: 1156] (through reference chain: io.fabric8.kubernetes.api.model.WatchEvent["object"])
            at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:164) ~[jackson-databind-2.4.1.jar:2.4.1]
            at com.fasterxml.jackson.databind.DeserializationContext.mappingException(DeserializationContext.java:757) ~[jackson-databind-2.4.1.jar:2.4.1]
            at io.fabric8.kubernetes.internal.KubernetesDeserializer.deserialize(KubernetesDeserializer.java:41) ~[kubernetes-model-1.0.3.jar:1.0.3]
            at io.fabric8.kubernetes.internal.KubernetesDeserializer.deserialize(KubernetesDeserializer.java:29) ~[kubernetes-model-1.0.3.jar:1.0.3]
            at com.fasterxml.jackson.databind.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:538) ~[jackson-databind-2.4.1.jar:2.4.1]
            at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:99) ~[jackson-databind-2.4.1.jar:2.4.1]
            at com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:242) ~[jackson-databind-2.4.1.jar:2.4.1]
            at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:118) ~[jackson-databind-2.4.1.jar:2.4.1]
            at com.fasterxml.jackson.databind.ObjectReader._bindAndClose(ObjectReader.java:1269) ~[jackson-databind-2.4.1.jar:2.4.1]
            at com.fasterxml.jackson.databind.ObjectReader.readValue(ObjectReader.java:896) ~[jackson-databind-2.4.1.jar:2.4.1]
            at io.fabric8.kubernetes.client.dsl.internal.BaseOperation$3.onMessage(BaseOperation.java:422) ~[kubernetes-client-1.2.2.jar:na]
            at com.ning.http.client.providers.netty.ws.NettyWebSocket.notifyTextListeners(NettyWebSocket.java:240) [async-http-client-1.9.29.jar:na]
            at com.ning.http.client.providers.netty.ws.NettyWebSocket.onTextFragment(NettyWebSocket.java:281) [async-http-client-1.9.29.jar:na]
            at com.ning.http.client.providers.netty.handler.WebSocketProtocol.handle(WebSocketProtocol.java:162) [async-http-client-1.9.29.jar:na]
            at com.ning.http.client.providers.netty.handler.Processor.messageReceived(Processor.java:88) [async-http-client-1.9.29.jar:na]
            at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.handler.codec.oneone.OneToOneDecoder.handleUpstream(OneToOneDecoder.java:68) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:296) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.handler.codec.frame.FrameDecoder.unfoldAndFireMessageReceived(FrameDecoder.java:462) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.handler.codec.replay.ReplayingDecoder.callDecode(ReplayingDecoder.java:536) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.handler.codec.replay.ReplayingDecoder.messageReceived(ReplayingDecoder.java:435) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:559) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:268) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:255) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.socket.nio.NioWorker.read(NioWorker.java:88) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.socket.nio.AbstractNioWorker.process(AbstractNioWorker.java:108) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:337) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:89) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.channel.socket.nio.NioWorker.run(NioWorker.java:178) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108) [netty-3.10.3.Final.jar:na]
            at org.jboss.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42) [netty-3.10.3.Final.jar:na]
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_45]
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_45]
            at java.lang.Thread.run(Thread.java:745) [na:1.8.0_45]
4

1 に答える 1

3

スタック トレースを見ると、古いバージョンの fabric8 kubernetes クライアントを使用していることがわかります (しばらく前に async-http-client から okhttp に移行しました)。まず、最新バージョンにアップグレードする必要があります (io.fabric8:kubernetes-client:1.3.90執筆時点)。イベントを監視するためのスニペットを次に示します。

Watch watch = client.events().inAnyNamespace().watch(new Watcher<Event>() {
    @Override
    public void eventReceived(Action action, Event resource) {
        logger.info("{}: {}", action, resource);
    }

    @Override
    public void onClose(KubernetesClientException e) {
        if (e != null) {
            e.printStackTrace();
            logger.error(e.getMessage(), e);
        }
    }
});

で監視したい名前空間を監視したい場合を除きますclient.events().inNamespace(...).watch(...)。

于 2016-05-18T08:25:12.303 に答える