[FLINK-15251] Fabric8FlinkKubeClient doesn't work if ingress has hostname but no IP

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.10.0
• Fix Version/s: 1.10.0
• Component/s: Deployment / Kubernetes
• Labels: pull-request-available

Environment

Kubernetes for Docker on MacOS

• Assignee: Yang Wang
• Reporter: Aljoscha Krettek
• Created: 13/Dec/19 16:37
• Updated: 17/Dec/19 09:20
• Resolved: 17/Dec/19 09:19

Description

In my setup the ingress has a hostname but no IP here: https://github.com/apache/flink/blob/f49e632bb290ded45b320f5d00ceaa1543a6bb1c/flink-kubernetes/src/main/java/org/apache/flink/kubernetes/kubeclient/Fabric8FlinkKubeClient.java#L199

This means that when I try to use the Kubernetes Executor I will get

Exception in thread "main" java.lang.NullPointerException: Address should not be null.
	at org.apache.flink.util.Preconditions.checkNotNull(Preconditions.java:75)
	at org.apache.flink.kubernetes.kubeclient.Endpoint.<init>(Endpoint.java:33)
	at org.apache.flink.kubernetes.kubeclient.Fabric8FlinkKubeClient.getRestEndpoint(Fabric8FlinkKubeClient.java:209)
	at org.apache.flink.kubernetes.KubernetesClusterDescriptor.lambda$createClusterClientProvider$0(KubernetesClusterDescriptor.java:82)
	at org.apache.flink.kubernetes.KubernetesClusterDescriptor.retrieve(KubernetesClusterDescriptor.java:106)
	at org.apache.flink.kubernetes.KubernetesClusterDescriptor.retrieve(KubernetesClusterDescriptor.java:53)
	at org.apache.flink.client.deployment.AbstractSessionClusterExecutor.execute(AbstractSessionClusterExecutor.java:60)
	at org.apache.flink.streaming.api.environment.StreamExecutionEnvironment.executeAsync(StreamExecutionEnvironment.java:1741)
	at org.apache.flink.streaming.api.environment.StreamExecutionEnvironment.executeAsync(StreamExecutionEnvironment.java:1712)
	at org.apache.flink.streaming.examples.statemachine.StateMachineExample.main(StateMachineExample.java:169)

I think we can just check if a hostname is set and use that if there is no IP.

Issue Links

• links to: GitHub Pull Request #10579
• links to: GitHub Pull Request #10592