Use --set-string for helm image values

[michaelbeaumont]

Fixes #1992, related to helm/helm#1707

Description

This prevents helm from interpreting tags as numbers, for example, short git commits made up of numeric characters.

User facing changes

n/a

Before

helm is called with the image and tag information using something like --set image.repository=container,image.tag=5678444 causing the tag to be interpreted as a number. This leads to Pods failing with InvalidImageName:

  Warning  InspectFailed  9s (x3 over 10s)  kubelet, minikube  Failed to apply default image tag "container:5.555559e+06": couldn't parse image reference "container:5.678444e+06": invalid reference format
  Warning  Failed         9s (x3 over 10s)  kubelet, minikube  Error: InvalidImageName

After

helm is called with the image and tag information using something like --set-string image.repository=container,image.tag=5678444, preventing 5678444 from being interpreted as a float.

Next PRs.

Submitter Checklist

These are the criteria that every PR should meet, please check them off as you
review them:

• Includes unit tests
• Mentions any output changes.
• Adds documentation as needed: user docs, YAML reference, CLI reference.
• Adds integration tests if needed.

Reviewer Notes

• The code flow looks good.
• Unit test added.
• User facing changes look good.

Release Notes

Examples of user facing changes:
- Skaffold config changes like
  e.g. "Add buildArgs to `Kustomize` deployer skaffold config."
- Bug fixes
  e.g. "Improve skaffold init behaviour when tags are used in manifests"
- Any changes in skaffold behavior
  e.g. "Artiface cachine is turned on by default."

[codecov]

Codecov Report

Merging #3313 into master will not change coverage.
The diff coverage is 100%.

Impacted Files	Coverage Δ
pkg/skaffold/deploy/helm.go	77.33% <100%> (ø)	⬆️

[balopat]

I hope that this won't cause issues where people would expect typed values (booleans, integers?)?

[michaelbeaumont]

I don't think so since it's only used for image.tag, image.repository, image.registry as far as I can tell. I can't imagine a case where someone expects anything but a string there.