action.yaml

name: Pull Request Preview
description: "Creates unique preview environments for Pull Requests on Google Cloud Run"

inputs:
  GOOGLE_CLOUD_PROJECT_ID:
    description: "Google Cloud Project ID you want to use."
    required: true
  GOOGLE_CLOUD_SERVICE_ACCOUNT_KEY:
    description: "Google Cloud Service Account KEY"
    required: true
  DOCKER_BUILD_ARGS:
    description: If you want to inject build params to docker build step.
    required: true
  CLOUD_RUN_SERVICE_NAME:
    description: "Google Cloud Run Service name you want to deploy"
    required: true
  CLOUD_RUN_REGION:
    description: "The region you want your service to run"
    required: true
  CLOUD_RUN_SECRETS:
    description: "Cloud Run secrets to mount or use env vars "
    required: false
    default: ""
  CLOUD_RUN_ENV_VARS:
    description: "Cloud Run env vars "
    required: false
    default: ""
  ARTIFACT_REGISTRY_REGION:
    description: "Google Artifact Registry region you want to use"
    required: true
  ARTIFACT_REGISTRY_REPO:
    description: "Google artifact Registry repository you want to store your build image in"
    required: true
  ARTIFACT_REGISTRY_IMAGE:
    description: "Google Artifact Registry image"
    required: true

outputs:
  PREVIEW_URL:
    description: "The url for the preview environment."
    value: ${{ steps.deploy.outputs.url }}

runs:
  using: "composite"
  steps:
    - uses: actions/checkout@v3

    - name: Add SHORT_SHA env property with commit short sha
      shell: bash
      run: echo "SHORT_SHA=`echo ${GITHUB_SHA} | cut -c1-8`" >> $GITHUB_ENV

    - name: Get url friendly branch name
      shell: bash
      run: |
        url=$(sed -E 's#refs/[^\/]*/##;s/[^a-zA-Z0-9]+/-/g;s/-+/-/g;s/^-*//;s/-*$//' <<<"${GITHUB_HEAD_REF}")
        tolower=${url,,}
        reduce=$(echo $tolower | cut -c -20)
        echo "BRANCH_URL=$(echo ${reduce%-})" >> $GITHUB_ENV

    - name: Setup Image Tag
      run: echo "docker_tag=preview_${{ env.BRANCH_URL }}_${{ env.SHORT_SHA }}" >> $GITHUB_ENV
      shell: bash

    - name: Setup Docker Buildx
      uses: docker/setup-buildx-action@v2

    - name: Auth Google Cloud
      uses: google-github-actions/auth@v1
      with:
        credentials_json: "${{ inputs.GOOGLE_CLOUD_SERVICE_ACCOUNT_KEY }}"

    - name: Set up Cloud SDK
      uses: google-github-actions/setup-gcloud@v1
      with:
        project_id: ${{ inputs.GOOGLE_CLOUD_PROJECT_ID }}

    - name: Setup Docker Auth
      shell: bash
      run: |-
        gcloud --quiet auth configure-docker ${{ inputs.ARTIFACT_REGISTRY_REGION }}-docker.pkg.dev

    - name: Setup AR image tag url
      shell: bash
      run: echo "ar_image_tag=${{ inputs.ARTIFACT_REGISTRY_REGION }}-docker.pkg.dev/${{ inputs.GOOGLE_CLOUD_PROJECT_ID }}/${{ inputs.ARTIFACT_REGISTRY_REPO }}/${{ inputs.ARTIFACT_REGISTRY_IMAGE }}:${{ env.docker_tag }}" >> $GITHUB_ENV

    - name: Building the Docker Image
      shell: bash
      run: |-
        docker build --tag "${{ env.ar_image_tag }}" --build-arg version="${{ env.docker_tag }}" ${{ inputs.DOCKER_BUILD_ARGS }} .

    - name: Push the Image to Google Artifact Registry
      shell: bash
      run: |-
        docker push ${{ env.ar_image_tag }}

    - id: "deploy"
      uses: "google-github-actions/deploy-cloudrun@v1"
      with:
        service: ${{ inputs.CLOUD_RUN_SERVICE_NAME }}
        image: ${{ env.ar_image_tag }}
        tag: ${{ env.BRANCH_URL }}
        region: ${{ inputs.CLOUD_RUN_REGION }}
        env_vars: ${{ inputs.CLOUD_RUN_ENV_VARS }}
        secrets: ${{ inputs.CLOUD_RUN_SECRETS }}

    - name: Comment the Link on Pull Request
      uses: actions/github-script@v6
      continue-on-error: true
      with:
        script: |
          // Get the existing comments.
          const {data: comments} = await github.rest.issues.listComments({
            owner: context.repo.owner,
            repo: context.repo.repo,
            issue_number: context.payload.number,
          })
          // Find any comment already made by the bot.
          const botComment = comments.find(comment => comment.user.id === 41898282)
          const commentBody = `✅ Changes in this PR is deployed. To view the working copy please visit the following link: \n\n\n🔗 ${{ steps.deploy.outputs.url }}`;
          if (botComment) {
            // If the comment exists, update it.
            await github.rest.issues.updateComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: botComment.id,
              body: commentBody
            })
          } else {
            // First time commenting.
            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.payload.number,
              body: commentBody
            })
          }

          // Create new deployment to post the preview link on PR.
          const deployment = await github.rest.repos.createDeployment({
            owner: context.repo.owner,
            repo: context.repo.repo,
            ref: context.payload.pull_request.head.sha,
            environment: 'stage',
            description: commentBody,
            required_contexts: []
          });

          // Setup environment_url so we can see the preview url on bottom of PR page
          await github.rest.repos.createDeploymentStatus({
            state: 'success',
            environment_url: `${{ steps.deploy.outputs.url }}`,
            owner: context.repo.owner,
            repo: context.repo.repo,
            deployment_id: deployment.data.id,
            auto_merge: false
          });