GitHub Action to validate multiple Helm charts at once

helm_chart_validate_matrix.yml

name: Validate Helm charts

on:
  push:
    branches: [ main, master ]
  pull_request:

jobs:
  validate:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        directory:
          - "charts/my_application_1"
          - "charts/my_application_2"
          - "charts/my_application_3"
    steps:
      - uses: actions/checkout@v3
      - name: Check if the Helm chart has changed
        uses: dorny/paths-filter@v2
        id: filter
        with:
          filters: |
            chart:
              - '${{ matrix.directory }}/**'
      - name: Copy environment-specific values for linting
        if: steps.filter.outputs.chart == 'true'
        run: mkdir ${{ matrix.directory }}/ci; cd ${{ matrix.directory }}/values; for i in *.yaml; do cp -v "${i}" "../ci/${i%.*}-values.${i##*.}"; done
      - name: Set up chart-testing
        if: steps.filter.outputs.chart == 'true'
        uses: helm/chart-testing-action@v2.3.1
      - name: Lint Helm chart with chart-testing
        if: steps.filter.outputs.chart == 'true'
        run: | 
          ct lint \
          --validate-maintainers=false \
          --charts ${{ matrix.directory }} \
          --chart-repos datadog=https://helm.datadoghq.com \
          --chart-repos goldilocks=https://charts.fairwinds.com/stable \
          --chart-repos ambassador=https://app.getambassador.io \
          --chart-repos lacework-agent=https://lacework.github.io/helm-charts \
          --chart-repos kube-state-metrics=https://prometheus-community.github.io/helm-charts