feat: IDNA awareness in the zone finder

[lexisother]

Description

Normalise domain names before looking them up in the zone ID mapping.

Fixes #5090

Checklist

• Unit tests updated
• End user documentation updated

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[k8s-ci-robot]

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[ivankatliarchuk]

/ok-to-test

[ivankatliarchuk]

/label tide/merge-method-squash

[lexisother]

@ivankatliarchuk Added a test for the warning log, hope it's fine like this!

[ivankatliarchuk]

Nice one. I'll try to execute smoke test on my side. If you have a working setup, could share results here as well.

[lexisother]

I don't have many results to share other than the before/after logs on my own cluster 😅

Without my changes:

DEBU[0004] Skipping record a.xn--ccka2b6azt.xn--q9jyb4c because no hosted zone matching record DNS Name was detected
DEBU[0004] Skipping record a.a.xn--ccka2b6azt.xn--q9jyb4c because no hosted zone matching record DNS Name was detected

With my changes:

time="2025-03-04T00:57:46Z" level=info msg="Changing record." action=CREATE record=a.xn--ccka2b6azt.xn--q9jyb4c ttl=1 type=A zone=49619bc8e3ea12578435348ffa4707f1
time="2025-03-04T00:57:46Z" level=info msg="Changing record." action=CREATE record=a.a.xn--ccka2b6azt.xn--q9jyb4c ttl=1 type=TXT zone=49619bc8e3ea12578435348ffa4707f1

[ivankatliarchuk]

So the solution seems legit. I did a research and found AWS related docs, they suggest to do exactly that.

If you're using the Route 53 API or one of the AWS SDKs, you can programmatically convert a Unicode value to Punycode.

[ivankatliarchuk]

Any chance you share you external-dns arguments as well?

[lexisother]

Yep! Sorry for the delayed response! 😅
Here's my options:

  values:
    image:
      registry: ghcr.io
      repository: lexisother/external-dns
      tag: idna-fix-3
      pullSecrets:
        - ghcr-login-secret
    txtPrefix: "%{record_type}."
    provider: cloudflare
    cloudflare:
      secretName: external-dns
      proxied: false

[ivankatliarchuk]

It's a bit tricky to undersand to be honest. Could you have a look/check deployment manifest in kubernetes? Need only arguments, not yaml values sry from helm.

Something like

args:
 - --source=service
  - --registry=txt
  - --policy=upsert
  - --provider=cloudflare

[lexisother]

Here's the args from the resulting deployment:

      args:
        - '--metrics-address=:7979'
        - '--log-level=info'
        - '--log-format=text'
        - '--policy=upsert-only'
        - '--provider=cloudflare'
        - '--registry=txt'
        - '--interval=1m'
        - '--txt-prefix=%{record_type}.'
        - '--source=service'
        - '--source=ingress'
        - '--cloudflare-dns-records-per-page=100'

[ivankatliarchuk]

I was not able to test this PR due to bug that was fixed in this PR #5146. Any chance you rebase your changes so I could do final checks?

[lexisother]

@ivankatliarchuk Done.

[ivankatliarchuk]

/lgtm

cc: @mloiseleur

[mloiseleur]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ivankatliarchuk, mloiseleur

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