diff.yaml

name: Diff
permissions: {}

on:
  pull_request:
    branches:
      - main

jobs:
  generate-jobs:
    name: generate-jobs
    runs-on: ubuntu-latest
    permissions:
      contents: read
    outputs:
      changed: ${{ steps.list-changed.outputs.changed }}
      changed_list: ${{ steps.list-changed.outputs.changed_list }}
      values_files_json: ${{ steps.list-changed.outputs.values_files_json }}
    steps:
      - name: Checkout Code
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          fetch-depth: 0
          persist-credentials: false

      - name: Set up Helm
        uses: azure/setup-helm@dda3372f752e03dde6b3237bc9431cdc2f7a02a2 # v5.0.0
        with:
          # renovate: github=helm/helm
          version: v4.2.0

      - uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
        with:
          python-version: '3.14'

      - name: Set up chart-testing
        uses: helm/chart-testing-action@6ec842c01de15ebb84c8627d2744a0c2f2755c9f # v2.8.0
        with:
          # renovate: github=helm/chart-testing
          version: v3.14.0

      - name: Run chart-testing (list-changed)
        id: list-changed
        #language=bash
        run: |
          set -euo pipefail
          # get changed charts (one per line)
          changed=$(ct list-changed --config .github/linters/ct.yaml)

          # normalize and count changed charts
          changed_trimmed=$(echo "$changed" | sed '/^\s*$/d')
          num_changed=$(echo "$changed_trimmed" | sed '/^\s*$/d' | wc -l | tr -d ' ')

          if [[ -z "$changed_trimmed" ]]; then
            # nothing changed
            {
              echo "changed=false"
              echo "changed_list="
              echo "values_files_json=[]"
            } >> "$GITHUB_OUTPUT"
            exit 0
          fi

          if [ "$num_changed" -gt 1 ]; then
            echo "More than one chart changed (count=$num_changed). Failing."
            echo "$changed_trimmed"
            exit 1
          fi

          # single chart changed: compute ci/*-values.yaml files for that chart
          chart_path=$(echo "$changed_trimmed" | head -n1 | tr -d '"')
          # extract chart name (basename)
          chart_name=$(basename "$chart_path")

          values_json="[]"
          # look for ci/*-values.yaml under the chart directory
          # enable nullglob so the glob expands to empty array when no match
          shopt -s nullglob
          files=(charts/"$chart_name"/ci/*-values.yaml)
          if [ ${#files[@]} -gt 0 ]; then
            values_json="["
            sep=""
            for f in "${files[@]}"; do
              # ensure we only include files
              if [ -f "$f" ]; then
                # make path relative to workspace root
                relpath="$f"
                values_json+="$sep\"$relpath\""
                sep=","
              fi
            done
            values_json+="]"
          fi
          shopt -u nullglob

          {
            echo "changed=true"
            echo "changed_list=\"$chart_path\""
            echo "values_files_json=$values_json"
          } >> "$GITHUB_OUTPUT"

      # The following steps are only used to detect changes and produce the
      # list of values files. The per-values-file diff runs are executed in a
      # separate matrix job below.

  diff:
    name: diff
    needs: generate-jobs
    runs-on: ubuntu-latest
    if: needs.generate-jobs.outputs.changed == 'true'
    strategy:
      fail-fast: false
      matrix:
        valuefile: ${{ fromJson(needs.generate-jobs.outputs.values_files_json) }}
    steps:
      - name: Checkout Code
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          fetch-depth: 0
          persist-credentials: false

      - name: Set up Helm
        uses: azure/setup-helm@dda3372f752e03dde6b3237bc9431cdc2f7a02a2 # v5.0.0
        with:
          # renovate: github=helm/helm
          version: v4.2.0

      - name: install helm diff plugin
        run: helm plugin install https://github.com/databus23/helm-diff --version 3.15.4 --verify=false

      - name: Create kind cluster
        uses: helm/kind-action@ef37e7f390d99f746eb8b610417061a60e82a6cc # v1.14.0

      - name: Checkout Target of PR
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          path: target
          ref: ${{ github.event.pull_request.base.ref }}
          persist-credentials: false

      - name: Apply Gateway API CRDs
        run: kubectl apply -k https://github.com/kubernetes-sigs/gateway-api/config/crd

      - name: Apply KEDA CRDs
        run: kubectl apply --server-side -f "https://github.com/kedacore/keda/releases/download/v${KEDA_VERSION}/keda-${KEDA_VERSION}-crds.yaml"
        env:
          #renovate: github=kedacore/keda
          KEDA_VERSION: 2.19.0


      - name: Run diff for value file
        env:
          value_file: "${{ matrix.valuefile }}"
        #language=bash
        run: |
          set -euo pipefail
          IFS=$'\n\t'

          echo "Running diff for value file: $value_file"
          # extract chart name from path like charts/<chart>/ci/<file>
          # dirname twice: charts/<chart>/ci -> charts/<chart>, basename -> <chart>
          chart="$(basename "$(dirname "$(dirname "$value_file")")")"

          helm dependency update "./target/charts/$chart"
          helm dependency update "./charts/$chart"

          # install current target chart into cluster so helm diff has a baseline
          helm upgrade -i "$chart" "./target/charts/$chart" \
            --create-namespace \
            --namespace "$chart" \
            --wait \
            --values "$value_file"

          {
            printf '```diff\n'
            helm diff upgrade "$chart" "./charts/$chart" \
              --namespace "$chart" \
              --suppress=CustomResourceDefinition \
              --normalize-manifests \
              --reset-values \
              --no-color \
              -C 5 \
              --suppress-output-line-regex="helm.sh/chart:" \
              --suppress-output-line-regex="chart:" \
              --suppress-output-line-regex="app.kubernetes.io/version:" \
              --values "$value_file" | tee /dev/stderr
            printf '\n```'
          } > "$GITHUB_STEP_SUMMARY"