Creating a ServiceMonitor for *Kubernetes* client (not openshift)

[zenbones]

Is there any way to create a ServiceMonitor, as in..

apiVersion: monitoring.coreos.com/v1
kind: ServiceMonitor

If it isn't directly wrapped by the API, can I use the client to create/install an arbitrary type from string or JsonNode or... something?

[rohanKanojia]

Yes, you should be able to do it using the RAW API: https://github.com/fabric8io/kubernetes-client/blob/master/doc/CHEATSHEET.md#customresource-typeless-api

[zenbones]

Yes, I know I can, and that does work. I had opened this ticket before, which you responded to with the very nice work on ServiceMonitor you did for the OpenShift client. The problem is that I'm using the Kubernetes client. I guess I should bother to read the code and create a proper k8s version of ServiceMonitor, but my time is limited and the raw api does work fine, but the heart wants what the heart wants.

[rohanKanojia]

ohk, I see. I don't think it's possible to add ServiceMonitor in KubernetesClient Jar. Best I can think of is providing a prometheus extension that can have all POJOs for structs in github.com/coreos/prometheus-operator/pkg/apis/monitoring/v1 package.

If you just want to use ServiceMonitor with KubernetesClient using typed custom resource API. You can add this additional dependency in project which contains all monitoring model including ServiceMonitor:

<dependency>
  <groupId>io.fabric8</groupId>
  <artifactId>openshift-model-monitoring</artifactId>
  <version>5.0.0</version>
</dependency>

and then create a ServiceMonitor client like this:

try (KubernetesClient client = new DefaultKubernetesClient()) {
   // Create ServiceMonitor Client
   MixedOperation<ServiceMonitor, ServiceMonitorList, Resource<ServiceMonitor>> svcMonitorClient = client.customResources(ServiceMonitor.class);
   
   // Use Client for ServiceMonitor related operations
   svcMonitorClient.inNamespace("foo").list();

}

If you don't want to add additional dependency you can copy-paste ServiceMonitor POJOs into your project too(You can find them while building the project):

kubernetes-client : $ find . -iname ServiceMonitor*.java
./kubernetes-model-generator/openshift-model-monitoring/target/generated-sources/io/fabric8/openshift/api/model/monitoring/v1/ServiceMonitor.java
./kubernetes-model-generator/openshift-model-monitoring/target/generated-sources/io/fabric8/openshift/api/model/monitoring/v1/ServiceMonitorList.java
./kubernetes-model-generator/openshift-model-monitoring/target/generated-sources/io/fabric8/openshift/api/model/monitoring/v1/ServiceMonitorSpec.java

[zenbones]

Thank you, that's helpful. I'll poke around when I get a chance and see what works best. Feel free to close this ticket. Adding a small section in docs with advice similar to the above might be helpful for others as well.

[shouldnotappearcalm]

ohk, I see. I don't think it's possible to add ServiceMonitor in KubernetesClient Jar. Best I can think of is providing a prometheus extension that can have all POJOs for structs in github.com/coreos/prometheus-operator/pkg/apis/monitoring/v1 package.

If you just want to use ServiceMonitor with KubernetesClient using typed custom resource API. You can add this additional dependency in project which contains all monitoring model including ServiceMonitor:

<dependency>
  <groupId>io.fabric8</groupId>
  <artifactId>openshift-model-monitoring</artifactId>
  <version>5.0.0</version>
</dependency>

and then create a ServiceMonitor client like this:

try (KubernetesClient client = new DefaultKubernetesClient()) {
   // Create ServiceMonitor Client
   MixedOperation<ServiceMonitor, ServiceMonitorList, Resource<ServiceMonitor>> svcMonitorClient = client.customResources(ServiceMonitor.class);
   
   // Use Client for ServiceMonitor related operations
   svcMonitorClient.inNamespace("foo").list();

}

If you don't want to add additional dependency you can copy-paste ServiceMonitor POJOs into your project too(You can find them while building the project):

kubernetes-client : $ find . -iname ServiceMonitor*.java
./kubernetes-model-generator/openshift-model-monitoring/target/generated-sources/io/fabric8/openshift/api/model/monitoring/v1/ServiceMonitor.java
./kubernetes-model-generator/openshift-model-monitoring/target/generated-sources/io/fabric8/openshift/api/model/monitoring/v1/ServiceMonitorList.java
./kubernetes-model-generator/openshift-model-monitoring/target/generated-sources/io/fabric8/openshift/api/model/monitoring/v1/ServiceMonitorSpec.java

Hello i have a question,openshift-model-monitoring ServiceMonitor not extend CustomResource,how to use client.customResources(ServiceMonitor.class) directly

[rohanKanojia]

@shouldnotappearcalm: Hmm, I'm not sure if depending upon current CustomResource API you would be able to use it. Could you please create an issue for adding support for Prometheus Extension? It should be easy to implement.

[shouldnotappearcalm]

@rohanKanojia: This is how I use it now,but <T extends HasMetadata, L extends KubernetesResourceList<T>> MixedOperation<T, L, Resource<T>> customResources(CustomResourceDefinitionContext crdContext, Class<T> resourceType, Class<L> listClass) method is deprecated in 5.1.0

Config config = new ConfigBuilder().build();
KubernetesClient kubernetesClient = new DefaultKubernetesClient(config);
String crdName = "servicemonitors.monitoring.coreos.com";
CustomResourceDefinition crd = new ApiextensionsAPIGroupClient().v1beta1().customResourceDefinitions().withName(crdName).get();
MixedOperation<ServiceMonitor, ServiceMonitorList, Resource<ServiceMonitor>> svcMonitorClient = kubernetesClient.customResources(CustomResourceDefinitionContext.fromCrd(crd), ServiceMonitor.class, ServiceMonitorList.class);
ServiceMonitorList serviceMonitorList = svcMonitorClient.inNamespace("default").list();

[rohanKanojia]

Hmm, I see. We're discussing whether this should be part of API in future versions or not here #2738 . I think it should stay there since this can allow users to use same POJO for multiple versions too.

[shouldnotappearcalm]

Okay, the way I currently use can also achieve my needs

[rohanKanojia]

@shouldnotappearcalm : Bdw, I would appreciate it if you could add your comment on #2738 to make this method not deprecated . It would help us in making the right decision.

[shouldnotappearcalm]

I have added a comment to 2738

[iocanel]

@shouldnotappearcalm @rohanKanojia @zenbones: FWIW, we do have a client extension as part of dekorate: https://github.com/dekorateio/dekorate/tree/master/annotations/prometheus-annotations

The extension bits:

• client
• model

package should move to the client as extension, or at least that was the intention.
If anyone is up to the task, I wouldn't mind moving them there.

[rohanKanojia]

@iocanel : Could you please open a separate issue for this? I think we should do it. Right now our extensions also have mock module too but I think it should be easy to implement too.