chore(source): reduce cyclomatic complexity of extractNodePortTargets

[linolayani]

Description

Reducing cyclomatic complexity of the extractNodePortTargets function.

• move pod retrieval logic into a separated function
• move nodes retrieval logic into a separated function
• replace a switch definition with one case by a if/else statement
• replace 2 ifs statements by a switch definition

Related to #5419

Checklist

• Unit tests updated
• End user documentation updated

[k8s-ci-robot]

Hi @linoleparquet. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[ivankatliarchuk]

/ok-to-test

[ivankatliarchuk]

do you think is possible/not-to-difficult to cover error cases with tests in this method?

[linolayani]

Yep, wanted to, but I don't see an easy way to test these functions.. Also they are essentially basic calls to the apimachinery and client-go package, without custom logic. I'm not sure how much value unit testing these would add in this case. Happy to hear suggestions if you think there’s a good approach here

[ivankatliarchuk]

No probs. I know how to write tests, but too much to mock ;-). I'll have a look at some point, as I could imagine we may going to have quite few similar methods at some point.

[ivankatliarchuk]

/lgtm

[mloiseleur]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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