Support for multisource + upgrade k8s and argocd pkg

[deferraz]

This PR splits the necessary changes to have multisource support as requested by @jannfis
References:
#548
#564

Fixes #513

[jannfis]

Thanks for your PR!

Can you please take a look at the failing unit tests, as well as the failing DCO? The latter is usually fixed by signing off your commits (i.e. git commit -s).

[aaguilartablada]

I am very interested in this feature. @deferraz could you give attention to the PR? thanks!

[MaheshAravind]

hey any update on this PR? image updater is unusable if we use the argo terraform provider due to this.

[askhari]

In order to fix the error showed in the unit tests I should change some code back to the original and leave it like the suggestion below where the app.Spec.Source.Kustomize will be initialized:

Suggested change

	kustomizeSpec := app.Spec.GetSource().Kustomize
	app.Spec.Source.Kustomize = app.Spec.GetSource().Kustomize
	if app.Spec.Source.Kustomize == nil {
	app.Spec.Source.Kustomize = &v1alpha1.ApplicationSourceKustomize{}
	}
	for i, kImg := range app.Spec.Source.Kustomize.Images {
	curr := image.NewFromIdentifier(string(kImg))
	override := image.NewFromIdentifier(ksImageParam)
	if curr.ImageName == override.ImageName {
	curr.ImageAlias = override.ImageAlias
	app.Spec.Source.Kustomize.Images[i] = v1alpha1.KustomizeImage(override.String())
	}
	}
	app.Spec.Source.Kustomize.MergeImage(v1alpha1.KustomizeImage(ksImageParam))
	return nil

[askhari]

I added this snippet to fix the errors showed by the unit tests.

[askhari]

We tried this and it worked to some degree. But in the end, if you want to set the target writeback repository is a bit messy. It would be better to use an annotation.

There is already a merge in the master branch of this repository that adds an annotation to set the writeback repository using multisource, but it seems to fail in the unit tests.

Digging a bit into the code, for this to work properly, it will need some dependencies upgrades (specially the argocd depedency) and a much deeper refactor and development to add this feature.

[askhari]

I opened a new PR here (#636) with similar changes to this one but covering some issues that we found when we wanted to write back to Helm values files. I hope this helps.

Please, let me know if we should merge this to PR contents to have only one and work on that.

[teroahonen-vungle]

Would be awesome to get this approved

[artemlive]

Would be awesome to get this approved

Agree, we are looking for this feature too.

[chenfli]

Any news about this PR, we really need it

[devopsidiot]

Definitely need this on my team.

[naviat]

bump? need to add in the next release!

[baohuynh09-lxp]

bump? need to add in the next release!

[jannfis]

I think this now has been superseded by #636