selectiveNamespaces not working

[ElectroLutz]

Describe the bug
We're currently upgrading vom Spring Boot 3.5 to Spring Boot 4.1 and Spring Cloud 2025.1.2. We came across a weird behavior regarding the kubernetes auto-discovery.

We use Spring Cloud Kubenetes 5.0.2 with the following configuration:

spring:
  cloud:
    kubernetes:
      discovery:
        enabled: true
        namespaces:
          - some-namespace

after upgrading our discovery failed, because instead only querying the single given namespace it tried to do it cluster-wide. The service account, the pod has, doesn't allow this.

After debugging (for hours) we found out that creating a selectiveNamespaces (with s at the end) Bean with the desired namespace fixed the problem. Otherwise Spring would just collect some Strings (since it's defined as List) it could find as a Bean.

I think it might be related to this commits: df4fc11 10acbb9 5671518
They changed the name of the Bean quite a bit, but the final version is missing the s.

Or maybe we're doing something wrong. But I guess using some random defined String Beans for this is not the correct way anyway.

[wind57]

I'd like to help, but I am not sure what is going on.

Can you provide a sample that I can run and understand the issue you are facing?

[wind57]

this looks like either a bug on our side or some kind of miss-configuration. This config that you have provided:

spring:
  cloud:
    kubernetes:
      discovery:
        enabled: true
        namespaces:
          - some-namespace

definitely should work without any other beans that you define.

Otherwise Spring would just collect some Strings (since it's defined as List) it could find as a Bean

This should not happen, no.

because instead only querying the single given namespace it tried to do it cluster-wide.

This should not happen either.

---

When you provide a sample for me to reproduce, I will gladly figure it out.

Thank you.

@ryanjbaxter can you add the feedback label please?

[ElectroLutz]

Adding this test to KubernetesClientInformerDiscoveryClientAutoConfigurationApplicationContextTests should demonstrate the issue.

@Test
void shouldUseDefinedBeanForSelectiveNamespaces() {

	mockEndpointsAndServices(List.of("a", "b", "c", "d"), API_SERVER);

	setup("spring.main.cloud-platform=KUBERNETES", "spring.cloud.kubernetes.discovery.namespaces=a,b,c");
	applicationContextRunner
		// having this defined should not make the auto configuration break
		.withBean("anyProperty", String.class, () -> "d")
		.run(context -> {
			assertThat(context).hasSingleBean(KubernetesClientInformerDiscoveryClient.class);
			assertThat(context).hasSingleBean(KubernetesClientInformerReactiveDiscoveryClient.class);

			assertThat(context).getBeans(KubernetesDiscoveryClientHealthIndicatorInitializer.class).hasSize(2);
			assertThat(context).getBeans(ReactiveDiscoveryClientHealthIndicator.class).hasSize(2);
			// reactive is enabled and non-cacheable is the default option
			assertThat(context).hasBean("nonCacheableReactiveDiscoveryClientHealthIndicator");
			// from commons, not ours
			assertThat(context).hasBean("simpleReactiveDiscoveryClientHealthIndicator");

			// 3 namespaces
			assertInformerBeansPresent(context, 3); // it will be 1
		});
}

And you can fix the test by renaming the selectiveNamespace Bean to selectiveNamespaces.

[wind57]

oh! you're correct, this is a bug.

@ryanjbaxter please add the bug label, I'll fix it.