# This is a pre-release of a Helm 2to3 migration template to facilitate
# the migration of Auto DevOps releases to Helm 3.
#
# To use, set the CI variable MIGRATE_HELM_2TO3 to "true".
# For more details, go to https://docs.gitlab.com/ee/topics/autodevops/upgrading_auto_deploy_dependencies.html#helm-v3

.helm-2to3-migrate:
  image: registry.gitlab.com/gitlab-org/cluster-integration/helm-install-image/releases/helm-2to3-2.17.0-3.5.3-kube-1.16.15-alpine-3.12
  # NOTE: We use the deploy stage because:
  #   - It exists in all versions of Auto DevOps.
  #   - It is _empty_.
  #   - It precedes any Kubernetes deployments.
  # Users on older versions of GitLab can include this template without adjusting their stages.
  stage: deploy
  needs: []
  artifacts:
    when: always
    expire_in: 1 week
    paths:
      - helm-2-release-backups/
  before_script:
    - mkdir helm-2-release-backups
    - apk add jq
    - export TILLER_NAMESPACE=$KUBE_NAMESPACE
    - export HELM_HOST="localhost:44134"
    - nohup tiller -listen "${HELM_HOST}" >tiller.log 2>&1 &
    - helm2 init --client-only
  script:
    # check for releases
    - releases=$(helm2 ls --output json | jq -r '.Releases[].Name')
    # back up entire namespace if the user opts into it
    - |
      if [[ -n "$releases" && -n "$BACKUP_HELM2_RELEASES" ]]; then
        echo "Backing up releases"
        kubectl get configmap -n "$KUBE_NAMESPACE" -l "OWNER=TILLER" -o yaml > "helm-2-release-backups/$KUBE_NAMESPACE.yaml"
      fi
    # adopt manifests from each release
    - |
      for release in $releases; do
        chart=$(helm2 ls "^$release\$" --output json | jq -r '.Releases[0].Chart')
        echo "Adopting Helm v2 manifests from $release"
        # some resource kinds must be listed explicitly https://github.com/kubernetes/kubernetes/issues/42885
        for name in $(kubectl -n "$KUBE_NAMESPACE" get all,ingress,daemonset -o name -l chart="$chart"); do
          kubectl annotate -n "$KUBE_NAMESPACE" --overwrite "$name" meta.helm.sh/release-name="$release"
          kubectl annotate -n "$KUBE_NAMESPACE" --overwrite "$name" meta.helm.sh/release-namespace="$KUBE_NAMESPACE"
          kubectl label -n "$KUBE_NAMESPACE" --overwrite "$name" app.kubernetes.io/managed-by=Helm
        done
      done
    # migrate each release
    - |
      for release in $releases; do
        echo "Migrating release: $release"
        helm3 2to3 convert --ignore-already-migrated --release-storage configmaps --tiller-out-cluster --tiller-ns "$TILLER_NAMESPACE" "$release"
      done

.helm-2to3-cleanup:
  image: registry.gitlab.com/gitlab-org/cluster-integration/helm-install-image/releases/helm-2to3-2.17.0-3.5.3-kube-1.16.15-alpine-3.12
  stage: cleanup
  environment:
    action: prepare
  before_script:
    - export TILLER_NAMESPACE=$KUBE_NAMESPACE
    - export HELM_HOST="localhost:44134"
    - nohup tiller -listen "${HELM_HOST}" >tiller.log 2>&1 &
    - helm2 init --client-only
  script:
    - helm3 2to3 cleanup --skip-confirmation --release-storage configmaps --tiller-out-cluster --tiller-ns "$TILLER_NAMESPACE"

.review:
  environment:
    name: review/$CI_COMMIT_REF_NAME
  rules:
    - if: '$MIGRATE_HELM_2TO3 != "true"'
      when: never
    - if: '$CI_KUBERNETES_ACTIVE == null || $CI_KUBERNETES_ACTIVE == ""'
      when: never
    - if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH'
      when: never
    - if: '$REVIEW_DISABLED'
      when: never
    - if: '$CI_COMMIT_TAG || $CI_COMMIT_BRANCH'
      when: manual

review:helm-2to3:migrate:
  extends: [.review, .helm-2to3-migrate]

review:helm-2to3:cleanup:
  extends: [.review, .helm-2to3-cleanup]
  rules:
    - if: '$MIGRATE_HELM_2TO3 != "true" && $CLEANUP_HELM_2TO3 == null'
      when: never
    - if: '$CI_KUBERNETES_ACTIVE == null || $CI_KUBERNETES_ACTIVE == ""'
      when: never
    - if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH'
      when: never
    - if: '$REVIEW_DISABLED'
      when: never
    - if: '$CI_COMMIT_TAG || $CI_COMMIT_BRANCH'
      when: manual

.staging:
  environment:
    name: staging
  rules:
    - if: '$MIGRATE_HELM_2TO3 != "true"'
      when: never
    - if: '$CI_KUBERNETES_ACTIVE == null || $CI_KUBERNETES_ACTIVE == ""'
      when: never
    - if: '$CI_COMMIT_BRANCH != $CI_DEFAULT_BRANCH'
      when: never
    - if: '$STAGING_ENABLED'
      when: manual

staging:helm-2to3:migrate:
  extends: [.staging, .helm-2to3-migrate]

staging:helm-2to3:cleanup:
  extends: [.staging, .helm-2to3-cleanup]
  rules:
    - if: '$MIGRATE_HELM_2TO3 != "true" && $CLEANUP_HELM_2TO3 == null'
      when: never
    - if: '$CI_KUBERNETES_ACTIVE == null || $CI_KUBERNETES_ACTIVE == ""'
      when: never
    - if: '$CI_COMMIT_BRANCH != $CI_DEFAULT_BRANCH'
      when: never
    - if: '$STAGING_ENABLED'
      when: manual

.production:
  environment:
    name: production
  rules:
    - if: '$MIGRATE_HELM_2TO3 != "true"'
      when: never
    - if: '$CI_KUBERNETES_ACTIVE == null || $CI_KUBERNETES_ACTIVE == ""'
      when: never
    - if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH'
      when: manual

production:helm-2to3:migrate:
  extends: [.production, .helm-2to3-migrate]

production:helm-2to3:cleanup:
  extends: [.production, .helm-2to3-cleanup]
  rules:
    - if: '$MIGRATE_HELM_2TO3 != "true" && $CLEANUP_HELM_2TO3 == null'
      when: never
    - if: '$CI_KUBERNETES_ACTIVE == null || $CI_KUBERNETES_ACTIVE == ""'
      when: never
    - if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH'
      when: manual