Feature/allow no exists helmvalues file

[will4j]

I have a multi sources Application like below

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  annotations:
    argocd-image-updater.argoproj.io/write-back-method: git
    argocd-image-updater.argoproj.io/write-back-target: helmvalues:/image-updater/.argocd-source-xyz-app-test.yaml
    argocd-image-updater.argoproj.io/git-repository: https://github.com/abc/xyz
    argocd-image-updater.argoproj.io/git-branch: release/prod
    argocd-image-updater.argoproj.io/image-list: client=harbor.abc.com/xyz-client,job=harbor.abc.com/xyz-job
    argocd-image-updater.argoproj.io/job.allow-tags: regexp:^test-sha-[0-9a-f]{7}$
    argocd-image-updater.argoproj.io/job.helm.image-tag: xyzJob.image.tag
    argocd-image-updater.argoproj.io/job.update-strategy: newest-build
    argocd-image-updater.argoproj.io/client.allow-tags: regexp:^test-sha-[0-9a-f]{7}$
    argocd-image-updater.argoproj.io/client.helm.image-tag: xyzClient.image.tag
    argocd-image-updater.argoproj.io/client.update-strategy: newest-build
  name: xyz-app-test
  namespace: argocd
spec:
  sources:
  - chart: xyz-app
    helm:
      ignoreMissingValueFiles: true
      releaseName: xyz-app
      valueFiles:
      - $values/apps-base/xyz-app/values-test.yaml
      - $values/image-updater/.argocd-source-xyz-app-test.yaml
    repoURL: harbor.abc.com/charts
    targetRevision: 1.0.0
  - ref: values
    repoURL: https://github.com/abc/abc-deploy
    targetRevision: release/prod

after deploy this app, argocd image updater will show failed logs

level=info msg="git checkout --force release/prod" dir=/tmp/git-xyz-app-test execID=49aae
level=info msg=Trace args="[git checkout --force release/prod]" dir=/tmp/git-xyz-app-test operation_name="exec git" time_ms=38.132636
level=info msg="git clean -ffdx" dir=/tmp/git-xyz-app-test execID=9f728
level=info msg=Trace args="[git clean -ffdx]" dir=/tmp/git-xyz-app-test operation_name="exec git" time_ms=2.081065
level=error msg="Could not update application spec: failed to set image parameter version value: unexpected type  for root" application=git-xyz-app-test

I found this is because when target file not exists, it will use nil originalData to marshal params override, which will failed when try to set helm value to wrong kind of yaml Node, like it explained here.

and the call entry is like below:

argocd-image-updater/pkg/argocd/git.go

Lines 319 to 337 in c6167ec

	if targetExists {
	originalData, err = os.ReadFile(targetFile)
	if err != nil {
	return err, false
	}
	override, err = marshalParamsOverride(app, originalData)
	if err != nil {
	return
	}
	if string(originalData) == string(override) {
	logCtx.Debugf("target parameter file and marshaled data are the same, skipping commit.")
	return nil, true
	}
	} else {
	override, err = marshalParamsOverride(app, nil)
	if err != nil {
	return
	}
	}

This pr is intend to solve the problem by create a empy yaml.DocumentNode when originalData is nil, Therefore commit a new file to git when target file is not exists.

a new files likes:

# auto generated by argocd image updater

xyzClient:
  image:
    tag: test-sha-c103907
xyzJob:
  image:
    tag: test-sha-f19def5

This may solve #1108 .

[codecov-commenter]

Codecov Report

❌ Patch coverage is 85.71429% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 63.52%. Comparing base (e6c82f2) to head (496c5bf).

Files with missing lines	Patch %	Lines
pkg/argocd/update.go	85.71%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1212      +/-   ##
==========================================
+ Coverage   63.33%   63.52%   +0.18%     
==========================================
  Files          23       23              
  Lines        3175     3191      +16     
==========================================
+ Hits         2011     2027      +16     
  Misses       1054     1054              
  Partials      110      110              

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[chengfang]

I noticed your target helm values file is named ".argocd-source-xyz-app-test.yaml". Do you still see the problem when the name does not start with .argocd-source-*? This prefix is used as the default target for git write-back.

[will4j]

I noticed your target helm values file is named ".argocd-source-xyz-app-test.yaml". Do you still see the problem when the name does not start with .argocd-source-*? This prefix is used as the default target for git write-back.

actually the pattern of filename is not limited here, I just named with prefix .argocd-source to identity these files auto generated by argo, which means argocd image updater here.

---

Further more, as I understand, .argocd-source-*.yaml file is the extra parameter file auto recognized by argocd, and it should placed at the source root dir, which is the dir where the chart is pulled and extracted to in my multiple sources application. so none of .argocd-source-*.yaml files in the ref repo(which is invisible when generate manifests of the helm chart) will take effect, it takes me lots of time to find out.

So in another case, if remove argocd-image-updater.argoproj.io/write-back-target annotation and argocd image updater do successfully generate a .argocd-source-*.yaml file to the ref repo, which is the default behavior, it will not work as the file not used when rendering helm chart, currently i don't see a way to let .argocd-source-*.yaml file to work with remote helm repo source without extra user config, that's why I add .argocd-source-xyz-app-test.yaml to the valuesFiles of helm chart repo in my application.