[fix][client] Fix tenant's allowedClusters is not updated when removing cluster

[ubo-dev]

Fixes #21546

Main Issue: #21546

Motivation

After deletion of cluster, tenant's allowed clusters Set is not updated. The deleted clusters is still available in there.

Modifications

I have edited the delete cluster method in CmdCluster file to update tenant's allowed cluster set when deletion of cluster occurs.

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• Make sure that the change passes the CI checks.

Does this pull request potentially affect one of the following parts:

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• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment

Documentation

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Matching PR in forked repository

PR in forked repository: PR

[ubo-dev]

I did try to add some test for this case but I have struggled a little. In AdminApiTest class there is a test that is for listing, creation, deletion for clusters. When I try to test this case, it does not run through CmdClusters, so I couldn't test it.
admin.clusters().deleteCluster(cluster);
This line takes deletion to a part that is after where my code is appears.
What do you suggest in this situation. Where I can write the test of this case.

[Technoboy-]

I did try to add some test for this case but I have struggled a little. In AdminApiTest class there is a test that is for listing, creation, deletion for clusters. When I try to test this case, it does not run through CmdClusters, so I couldn't test it. admin.clusters().deleteCluster(cluster); This line takes deletion to a part that is after where my code is appears. What do you suggest in this situation. Where I can write the test of this case.

Add test in TestCmdClusters

[ubo-dev]

@Technoboy- I have added delete cluster without delete all option test. Could you review it?

[ubo-dev]

Hey, I've accidentally closed the PR, I've added the required tests and opened it again @Technoboy- Could you review it?

[poorbarcode]

So far, Pulsar did not allow to create a tenant with empty clusters, see https://github.com/apache/pulsar/blob/master/pulsar-broker/src/main/java/org/apache/pulsar/broker/admin/impl/TenantsBase.java#L268-L273

// empty cluster shouldn't be allowed
if (info == null || info.getAllowedClusters().stream().filter(c -> !StringUtils.isBlank(c))
        .collect(Collectors.toSet()).isEmpty()
        || info.getAllowedClusters().stream().anyMatch(ac -> StringUtils.isBlank(ac))) {
    log.warn("[{}] Failed to validate due to clusters are empty", clientAppId());
    return FutureUtil.failedFuture(new RestException(Status.PRECONDITION_FAILED, "Clusters can not be empty"));
}

If the clusters only have one element (@param cluster), should we delete this tenant or throw an error? If no, it will break the limitation above.

/cc @codelipenghui @Technoboy-

[ubo-dev]

IMO, we should throw an error since tenant with empty clusters is not allowed. @Technoboy- @poorbarcode