Add support for private registry with custom port in restic-helper image

[cognoz]

Closes #1972

example of image definition with custom registry port in CM:

data:
  image: nexus-registry.domain.domain:18116/heptio-images/velero-restic-restore-helper:v1.1.0

[skriss]

Thanks for the PR @cognoz! We do need you to add DCO signoff to your commit -- git commit --amend --signoff followed by git push -f should do the trick.

[skriss]

@cognoz I think the code looks reasonable. I would like to add a couple new test cases though:

• one for an image name that doesn't have a / (i.e. len(parts) == 1) - validate that the default image is returned
• one for an image that uses a custom port for the registry, and doesn't have a tag - validate that the tag gets added
• one for an image that uses a custom port for the registry, and does have a tag - validate that it's returned as-is

You should be able to just copy/paste and modify from the existing test cases. Once that's done, I think we can merge this.

[skriss]

@cognoz thanks for making the updates, this LGTM! One last request - could you add a changelog with a brief description of the bug fix? See https://velero.io/docs/master/code-standards/ for details.

[skriss]

LGTM pending changelog.

[skriss]

cc @carlisia @prydonius @nrb - PTAL

[cognoz]

Changelog added, thx for guidelines!

[skriss]

@carlisia @nrb @prydonius ping - this one's waiting for review/merge.

[carlisia]

I like the new test, but is there a possibility for a case where the config map could haev invalid data in the key? If possible I'd like to make it so the modified test is an additional test, and keep the case for config map with invalid data in 'image' key returns default image.

[skriss]

@carlisia if you look at the code you'll notice that we're no longer trying to split image names based on :, so the test case you're referring to isn't really the best test of the logic anymore. The replacement case that was added (an image without a /) is effectively the "invalid data" case now, and validates that the default image is returned in such a case.

[carlisia]

👍