kubernetesClient.resources(HasMetadata.class).inNamespace("default").withLabels(Map.of("foo", "bar").list() throws NullPointerException

[stefanbethke]

Describe the bug

When trying to obtain a list of any resource matching a certain set of labels, a NullPointerException is thrown.

foo = kubernetesClient.resources(HasMetadata.class).inNamespace("default").withLabels(Map.of("foo", "bar").list()

The NPE is thrown here io.fabric8.kubernetes.client.dsl.base.OperationSupport#getRootUrl:

      return new URL(URLUtils.join(config.getMasterUrl().toString(), "api", apiGroupVersion));

apiGroupVersion is null at this point.

I'm sure I'm invoking the API incorrectly, but I couldn't find how to do this in a different way.

I'm using the operator, and I think it's pulling in the client version 5.12, but I can't select that below.

Fabric8 Kubernetes Client version

5.10.0

Steps to reproduce

Run Java code as shown above and observe the NPE.

Expected behavior

A list of resources is returned.

Runtime

other (please specify in additional context)

Kubernetes API Server version

1.22.3@latest

Environment

macOS

Fabric8 Kubernetes Client Logs

No response

Additional context

v1.22.6+k3s1 (k3d)

[shawkins]

This is not currently expected to work, but it should throw a better exception. There's currently no facility for scanning all resources in a given namespace. See the workaround and the issue in general #887 (comment)

[manusa]

This issue should be closed after we implement a fix that logs a better message.

In any case, it shouldn't be supported a .resources(HasMetadata.class). Operations to query on multiple resource types should be more explicit.

[rohanKanojia]

I can reproduce this issue on v5.12.2

However, on the master branch(6.0-SNAPSHOT) I can't. Instead, client proceeds to request resources for hasmetadatas:

May 10, 2022 2:37:36 PM okhttp3.mockwebserver.MockWebServer$2 execute
INFO: MockWebServer[42711] starting to accept connections
May 10, 2022 2:37:36 PM okhttp3.mockwebserver.MockWebServer$2 execute
INFO: MockWebServer[54931] starting to accept connections
May 10, 2022 2:37:36 PM okhttp3.mockwebserver.MockWebServer$3 processOneRequest
INFO: MockWebServer[54931] received request: GET /api/v1/hasmetadatas?labelSelector=foo%3Dbar HTTP/1.1 and responded: HTTP/1.1 404 Client Error
May 10, 2022 2:37:36 PM okhttp3.mockwebserver.MockWebServer$2 acceptConnections
INFO: MockWebServer[54931] done accepting connections: Socket closed

io.fabric8.kubernetes.client.KubernetesClientException: Failure executing: GET at: https://localhost:54931/api/v1/hasmetadatas?labelSelector=foo%3Dbar. Message: Not Found.

	at io.fabric8.kubernetes.client.dsl.internal.OperationSupport.requestFailure(OperationSupport.java:735)
	at io.fabric8.kubernetes.client.dsl.internal.OperationSupport.requestFailure(OperationSupport.java:713)
	at io.fabric8.kubernetes.client.dsl.internal.OperationSupport.assertResponseCode(OperationSupport.java:664)
	at io.fabric8.kubernetes.client.dsl.internal.OperationSupport.lambda$handleResponse$0(OperationSupport.java:580)
	at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:642)
	at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:506)
	at java.base/java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:2073)
	at io.fabric8.kubernetes.client.okhttp.OkHttpClientImpl$4.onResponse(OkHttpClientImpl.java:263)
	at okhttp3.RealCall$AsyncCall.execute(RealCall.java:203)
	at okhttp3.internal.NamedRunnable.run(NamedRunnable.java:32)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:834)


Process finished with exit code 255

[sachinkaushik]

#Hi @rohanKanojia @manusa @shawkins @thiagoarrais ,

I'm getting below exception, when we try to watch Openshift resource using the provided code.

Exception :: Caused by: java.lang.IllegalArgumentException: resources cannot be called with an interface

CODE::

      ` client.resources(HasMetadata.class).inAnyNamespace().watch(new Watcher<HasMetadata>() {
        @Override
        public void eventReceived(Action action, HasMetadata hasMetadata) {                
          
         
        }

        @Override
        public void onClose(WatcherException e) {

        }
    });`

Maven dep ::

<dependency> <groupId>io.fabric8</groupId> <artifactId>openshift-client</artifactId> <version>6.2.0</version> </dependency>

Is there anyway to watch all resources in single watcher, we tried to use Event, but that doesn't has all metadata of resource.
Can you please help here ?

Thank you in advance :)

[manusa]

Is there anyway to watch all resources in single watcher, we tried to use Event, but that doesn't has all metadata of resource.
Can you please help here ?

No, it's not possible. The Kubernetes API doesn't offer such feature.
You have to open a watcher for each resource you want to observe (Pod, Service, and so on)