Adds more proactive shutdown of informers

Also moving / tweaking the log of client closure

Closes fabric8io#5327

CHANGELOG.md

@@ -8,6 +8,7 @@
 * Fix #5423: OkHttpClientImpl supports setting request method for empty payload requests
 
 #### Improvements
+* Fix #5327: added proactive shutdown of informers on client close
 * Fix #5368: added support for additional ListOptions fields
 * Fix #5377: added a createOr and unlock function to provide a straight-forward replacement for createOrReplace.
 * Fix #5388: [crd-generator] Generate deterministic CRDs

httpclient-okhttp/src/main/java/io/fabric8/kubernetes/client/okhttp/OkHttpClientImpl.java

@@ -55,9 +55,7 @@
 import java.io.BufferedInputStream;
 import java.io.IOException;
 import java.io.InterruptedIOException;
-import java.io.PrintWriter;
 import java.io.Reader;
-import java.io.StringWriter;
 import java.lang.reflect.Method;
 import java.net.MalformedURLException;
 import java.nio.ByteBuffer;
@@ -250,15 +248,6 @@ public OkHttpClientImpl(OkHttpClient client, OkHttpClientBuilderImpl builder) {
 
   @Override
   public void close() {
-    if (LOG.isDebugEnabled()) {
-      StringWriter writer = new StringWriter();
-      PrintWriter printWriter = new PrintWriter(writer);
-      new Exception().printStackTrace(printWriter);
-      printWriter.close();
-      String stack = writer.toString();
-      stack = stack.substring(stack.indexOf("\n"));
-      LOG.debug("Shutting down dispatcher {} at the following call stack: {}", this.httpClient.dispatcher(), stack);
-    }
     ConnectionPool connectionPool = httpClient.connectionPool();
 
     Dispatcher dispatcher = httpClient.dispatcher();

kubernetes-client/src/main/java/io/fabric8/kubernetes/client/dsl/internal/BaseOperation.java

@@ -51,6 +51,7 @@
 import io.fabric8.kubernetes.client.dsl.base.PatchType;
 import io.fabric8.kubernetes.client.extension.ExtensibleResource;
 import io.fabric8.kubernetes.client.http.HttpRequest;
+import io.fabric8.kubernetes.client.impl.BaseClient;
 import io.fabric8.kubernetes.client.informers.ResourceEventHandler;
 import io.fabric8.kubernetes.client.informers.SharedIndexInformer;
 import io.fabric8.kubernetes.client.informers.impl.DefaultSharedIndexInformer;
@@ -1037,6 +1038,7 @@ private DefaultSharedIndexInformer<T, L> createInformer(long resync, Executor ex
     if (indexers != null) {
       informer.addIndexers(indexers);
     }
+    this.context.getClient().adapt(BaseClient.class).getClosed().whenComplete((closed, ignored) -> informer.stop());
     return informer;
   }
 

kubernetes-client/src/main/java/io/fabric8/kubernetes/client/impl/BaseClient.java

@@ -41,18 +41,23 @@
 import io.fabric8.kubernetes.client.utils.ApiVersionUtil;
 import io.fabric8.kubernetes.client.utils.KubernetesSerialization;
 import io.fabric8.kubernetes.client.utils.Utils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.net.HttpURLConnection;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.List;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.function.Predicate;
 
 public abstract class BaseClient implements Client {
 
+  public static final Logger logger = LoggerFactory.getLogger(BaseClient.class);
+
   /**
    * An {@link ExecutorSupplier} that provides an unlimited thread pool {@link Executor} per client.
    */
@@ -84,10 +89,12 @@ public void onClose(Executor executor) {
   private ExecutorSupplier executorSupplier;
   private Executor executor;
   protected KubernetesSerialization kubernetesSerialization;
+  private CompletableFuture<Void> closed;
 
   private OperationContext operationContext;
 
   BaseClient(BaseClient baseClient) {
+    this.closed = baseClient.closed;
     this.config = baseClient.config;
     this.httpClient = baseClient.httpClient;
     this.adapters = baseClient.adapters;
@@ -104,6 +111,7 @@ public void onClose(Executor executor) {
 
   BaseClient(final HttpClient httpClient, Config config, ExecutorSupplier executorSupplier,
       KubernetesSerialization kubernetesSerialization) {
+    this.closed = new CompletableFuture<>();
     this.config = config;
     this.httpClient = httpClient;
     this.handlers = new Handlers();
@@ -136,13 +144,22 @@ protected void setDerivedFields() {
 
   @Override
   public synchronized void close() {
+    if (closed.complete(null) && logger.isDebugEnabled()) {
+      logger.debug(
+          "The client and associated httpclient {} have been closed, the usage of this or any client using the httpclient will not work after this",
+          httpClient.getClass().getName());
+    }
     httpClient.close();
     if (this.executorSupplier != null) {
       this.executorSupplier.onClose(executor);
       this.executorSupplier = null;
     }
   }
 
+  public CompletableFuture<Void> getClosed() {
+    return closed;
+  }
+
   @Override
   public URL getMasterUrl() {
     return masterUrl;

kubernetes-tests/src/test/java/io/fabric8/kubernetes/client/mock/DefaultSharedIndexInformerTest.java

@@ -1204,6 +1204,23 @@ void testCustomExceptionHandler() throws InterruptedException {
     assertEquals(0, foundExistingAnimal.getCount());
   }
 
+  @Test
+  void testClientStopClosesInformer() throws InterruptedException {
+    // Given
+    setupMockServerExpectations(Animal.class, "ns1", this::getList,
+        r -> new WatchEvent(getAnimal("red-panda", "Carnivora", r), "ADDED"), null, null);
+
+    // When
+    SharedIndexInformer<GenericKubernetesResource> animalSharedIndexInformer = client
+        .genericKubernetesResources(animalContext)
+        .inNamespace("ns1")
+        .runnableInformer(60 * WATCH_EVENT_EMIT_TIME);
+
+    client.close();
+
+    assertTrue(animalSharedIndexInformer.stopped().toCompletableFuture().isDone());
+  }
+
   private KubernetesResource getAnimal(String name, String order, String resourceVersion) {
     AnimalSpec animalSpec = new AnimalSpec();
     animalSpec.setOrder(order);