feat(source/f5-virtual-server): add host aliases support for Virtual …

[shkarface]

What does it do ?

This PR implements support for the F5 VirtualServer's hostAliases field, allowing users to create DNS records for multiple hostnames from a single VirtualServer resource.

Motivation

The F5 VirtualServer source currently only creates DNS records for the primary hostname specified in spec.host. However, F5 VirtualServer resources support a hostAliases field that allows specifying additional hostnames that should resolve to the same targets. This PR implements support for this field to provide a more complete and useful integration.

More

• Yes, this PR title follows Conventional Commits
• Yes, I added unit tests
• Yes, I updated end user documentation accordingly

Changes Made

Implementation

• Added hostAliases processing in source/f5_virtualserver.go
• Maintains consistency by using the same targets, TTL, and resource labels for all hostnames

Testing

• Added 5 comprehensive test cases covering various scenarios:
  • Basic hostAliases functionality
  • hostAliases with target annotations
  • hostAliases with TTL annotations
  • Empty hostAliases handling
  • hostAliases with empty strings (edge case handling)

Documentation

• Enhanced docs/sources/f5-virtualserver.md with:
  • Detailed explanation of how the source works
  • Example VirtualServer configuration with hostAliases
  • Target priority explanation
  • TTL support documentation
  • Annotation filtering information

Example Usage

apiVersion: cis.f5.com/v1
kind: VirtualServer
metadata:
  name: example-vs
  namespace: default
spec:
  host: www.example.com
  hostAliases:
    - alias1.example.com
    - alias2.example.com
  virtualServerAddress: 192.168.1.100

This configuration will create DNS A records for:

• www.example.com → 192.168.1.100
• alias1.example.com → 192.168.1.100
• alias2.example.com → 192.168.1.100

Testing

All existing tests pass, and 5 new test cases have been added specifically for hostAliases functionality. The implementation handles edge cases like empty strings and maintains backward compatibility.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: shkarface / name: Shkar T. Noori (774d9a8, ad0e30e, 9f33131, 9800437)

[k8s-ci-robot]

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[k8s-ci-robot]

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[ivankatliarchuk]

Was this tested on a real cluster?

[mloiseleur]

/ok-to-test

[shkarface]

Was this tested on a real cluster?

Yes, we're utilizing this in all our clusters

Edit: worth to mention that we have had this change in our setup for almost a year as of now.

[mloiseleur]

/test pull-external-dns-unit-test

[mloiseleur]

/lgtm

[shkarface]

@szuecs fixed

[shkarface]

@mloiseleur can you please review this whenever you have time?

[mloiseleur]

@shkarface It's still lgtm. I'll let @szuecs proceed with a final review.
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: szuecs

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[szuecs]

Thanks for the ping and PR!