k8s-prepare.yml

name: 'K8s: Prepare k8s-manifests Deploy PR'

on:
  push:
    branches: [ releases/k8s-manifests ]

env:
  BRANCH_RELEASE: releases/k8s-manifests
  BRANCH_DEPLOY: deploys/k8s-manifests


jobs:

  k8s-prepare:
    runs-on: ubuntu-latest
    steps:

    - uses: actions/checkout@v2
      with:
        ref: ${{ env.BRANCH_RELEASE }}

    - name: Configure .kube/config
      run: |
        test -e ~/.kube || mkdir ~/.kube

        echo "${{ secrets.KUBECONFIG_BASE64 }}" | base64 -d > ~/.kube/config

    - name: Install kubectl-neat-diff
      run: |
        sudo wget https://github.com/sh0rez/kubectl-neat-diff/releases/download/v0.1.0/kubectl-neat-diff-linux-amd64 -O /usr/local/bin/kubectl-neat-diff
        sudo chmod +x /usr/local/bin/kubectl-neat-diff
        echo "KUBECTL_EXTERNAL_DIFF=kubectl-neat-diff" >> $GITHUB_ENV

    - name: Generate diff
      run: |
        (
          find . \
            -maxdepth 1 \
            -type d \
            -not -name '.*' \
            -print0 \
          | sort -z \
          | xargs -r0 -n 1 kubectl diff -Rf || true
        ) > /tmp/kube.diff

    - name: Create/update pull request
      env:
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      run: |
        ## build PR description body
        echo
        echo "Builing PR title+body content..."
        diff_size=$(wc -c /tmp/kube.diff | awk '{print $1}')
        pr_head_describe="$(git describe --always --tag)"

        pr_title="Deploy ${BRANCH_RELEASE} ${pr_head_describe}"
        pr_body="$(cat <<EOF
        \`kubectl diff\` reports that applying ${pr_head_describe} will change:

        \`\`\`diff
        $(if (( diff_size > 50000)); then echo 'diff too big; review locally'; else cat /tmp/kube.diff; fi)
        \`\`\`
        EOF
        )"


        ## generate initial commit for base if needed
        if ! git ls-remote --exit-code --heads origin "${BRANCH_DEPLOY}"; then
            echo
            echo "Existing branch ${BRANCH_DEPLOY} not found, generating initial commit..."
            git fetch origin --unshallow
            _first_projected_commit=$(git rev-list --max-parents=0 --first-parent HEAD)
            git push origin "${_first_projected_commit}:refs/heads/${BRANCH_DEPLOY}"
        fi


        ## check for existing PR
        echo
        echo "Looking for existing open PR for branch ${BRANCH_RELEASE}..."
        _existing_pr_number=$(
            gh pr list \
                --head "${BRANCH_RELEASE}" \
                --base "${BRANCH_DEPLOY}" \
                --state open \
                --limit 1 \
                --json number \
                --jq '.[0].number'
        )

        if [ -n "${_existing_pr_number}" ]; then
            echo
            echo "Found existing PR #${_existing_pr_number}, updating description..."
            pr_url=$(
                gh api "/repos/${GITHUB_REPOSITORY}/pulls/${_existing_pr_number}" \
                    --field title="${pr_title}" \
                    --field body="${pr_body}" \
                    --jq '.url'
            )
            echo "Updated PR: ${pr_url}"
        else
            echo
            echo "Opening PR..."
            pr_url=$(
                gh pr create \
                    --base "${BRANCH_DEPLOY}" \
                    --head "${BRANCH_RELEASE}" \
                    --title "${pr_title}" \
                    --body "${pr_body}"
            )
            pr_number="${pr_url##*/}"
            echo "Opened PR #${pr_number}"
        fi

    # - uses: mxschmitt/action-tmate@v3
    #   env:
    #     GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}