paramPrefix to go with pathParamPrefix

[Justin-DynamicD]

Summary

Add a paramPrefix to an application set git generator file template, so imported variables can be imported without fear of merge if desired.

Motivation

While pathParamPrefix can prevent duplicate .path variables from colliding/overwriting, it does not offer a way to protect other variables from overwriting each other. This would allow devs to comfortably accept yaml structures without fear of overwriting other arbitrary values from another when creating a composite.

Proposal

Implementation would be pretty straight forward, just an additional attribute I could use:

---
apiVersion: argoproj.io/v1alpha1
kind: ApplicationSet
metadata:
  name: yippie
spec:
  goTemplate: true
  generators:
    - matrix:
        generators:
          # git file generator referencing individual deployments
          - git:
              repoURL: https://github.com/me/myrepo.git
              revision: main
              files:
                - path: "coolyamls/*.yaml"
          # git file genereator referencing infrastructure
          - git:
              repoURL: https://github.com/me/myrepo.git
              revision: main
              files:
                - path: 'infrastructure/{{.infra_name}}.yaml'
              paramPrefix: infraVars
              pathParamPrefix: infraVars
  template:
    metadata:
      name: 'myapp-{{.path.filename | trimSuffix ".yaml"}}'
    spec:
      project: default
      source:
        helm:
          values: |
            {{.chart_values}}
            infravar: {{ .infraVars.chart_value}} 
        path: '{{.chart_path}}'
        repoURL: '{{.chart_url}}'
        targetRevision: '{{.chart_version}}'
      destination:
        name: '{{.path.filename | trimSuffix ".yaml"}}'
        namespace: 'thisplace'
      syncPolicy:
        automated:
          prune: true
          selfHeal: true
        syncOptions:
        - CreateNamespace=true
        - PrunePropagationPolicy=foreground
        - PruneLast=true
        retry:
          limit: 2
          backoff:
            duration: 5s
            factor: 2
            maxDuration: 3m

The idea here is that I can now group/pass multiple yaml files together and then choose if they overwrite each other or stay isolated simply by adding paramPrefix to each imported file.

[nikzayn]

@Justin-DynamicD Can I take this up?

[Justin-DynamicD]

@nikzayn by all means, please do!