rollback.yml

name: 롤백

on:
  workflow_dispatch:

jobs:
  rollback:
    runs-on: ubuntu-latest

    steps:
      - name: Setup SSH Key
        run: |
          echo "${{ secrets.EC2_SSH_KEY }}" > private_key.pem
          chmod 600 private_key.pem

      - name: Determine Current Version
        id: determine_current_version
        run: |
          CURRENT_VERSION=$(ssh -o StrictHostKeyChecking=no -i private_key.pem ubuntu@${{ secrets.EC2_HOST }} '
            if sudo docker ps --filter "name=splanet_blue" --filter "status=running" --format "{{.Names}}" | grep -q "splanet_blue"; then
              echo "blue"
            elif sudo docker ps --filter "name=splanet_green" --filter "status=running" | grep -q "splanet_green"; then
              echo "green"
            else
              echo "none"
            fi
          ')
          echo "current_version=$CURRENT_VERSION" >> $GITHUB_OUTPUT

      - name: Set Current and Previous Version Variables
        run: |
          echo "CURRENT_VERSION=${{ steps.determine_current_version.outputs.current_version }}" >> $GITHUB_ENV
          if [ "${{ env.CURRENT_VERSION }}" == "blue" ]; then
            echo "PREVIOUS_VERSION=green" >> $GITHUB_ENV
            echo "PREVIOUS_PORT=8081" >> $GITHUB_ENV
          else
            echo "PREVIOUS_VERSION=blue" >> $GITHUB_ENV
            echo "PREVIOUS_PORT=8080" >> $GITHUB_ENV
          fi

      - name: Start Previous Version
        uses: appleboy/ssh-action@v0.1.6
        with:
          host: ${{ secrets.EC2_HOST }}
          username: ubuntu
          key: ${{ secrets.EC2_SSH_KEY }}
          script: |
            PREVIOUS_VERSION=${{ env.PREVIOUS_VERSION }}
            echo "Starting previous version container: splanet_$PREVIOUS_VERSION"
            sudo docker start splanet_$PREVIOUS_VERSION

      - name: Wait for Previous Version to be Healthy
        uses: appleboy/ssh-action@v0.1.6
        with:
          host: ${{ secrets.EC2_HOST }}
          username: ubuntu
          key: ${{ secrets.EC2_SSH_KEY }}
          script: |
            PREVIOUS_PORT=${{ env.PREVIOUS_PORT }}
            echo "Waiting for the application to be healthy on http://localhost:${PREVIOUS_PORT}/actuator/health..."
            for i in {1..30}; do
              if curl -s http://localhost:$PREVIOUS_PORT/actuator/health | grep '"status":"UP"' > /dev/null; then
                echo "Application is healthy and ready to receive traffic."
                break
              fi
              echo "Waiting for application to start... (Attempt $i)"
              sleep 5
            done
            if [ "$i" -eq 30 ]; then
              echo "Application did not start successfully within the expected time."
              exit 1
            fi

      - name: Update Load Balancer Target Group
        uses: appleboy/ssh-action@v0.1.6
        with:
          host: ${{ secrets.EC2_HOST }}
          username: ubuntu
          key: ${{ secrets.EC2_SSH_KEY }}
          script: |
            CURRENT_VERSION=${{ env.CURRENT_VERSION }}
            PREVIOUS_VERSION=${{ env.PREVIOUS_VERSION }}

            if [ "$PREVIOUS_VERSION" == "blue" ]; then
              NEW_TARGET_GROUP_ARN="arn:aws:elasticloadbalancing:ap-northeast-2:${{ secrets.AWS_ACCOUNT_ID }}:targetgroup/splanet/${{ secrets.ARN_ID_8080 }}"
              OLD_TARGET_GROUP_ARN="arn:aws:elasticloadbalancing:ap-northeast-2:${{ secrets.AWS_ACCOUNT_ID }}:targetgroup/splanet-8081/${{ secrets.ARN_ID_8081 }}"
            else
              NEW_TARGET_GROUP_ARN="arn:aws:elasticloadbalancing:ap-northeast-2:${{ secrets.AWS_ACCOUNT_ID }}:targetgroup/splanet-8081/${{ secrets.ARN_ID_8081 }}"
              OLD_TARGET_GROUP_ARN="arn:aws:elasticloadbalancing:ap-northeast-2:${{ secrets.AWS_ACCOUNT_ID }}:targetgroup/splanet/${{ secrets.ARN_ID_8080 }}"
            fi

            echo "Gradually shifting traffic to previous version..."
            for i in {1..5}; do
              TRAFFIC_NEW=$((i * 20))
              TRAFFIC_OLD=$((100 - TRAFFIC_NEW))
              echo "Setting previous version traffic to $TRAFFIC_NEW% and current version to $TRAFFIC_OLD% (Step $i)"
            
              aws elbv2 modify-listener --listener-arn arn:aws:elasticloadbalancing:ap-northeast-2:${{ secrets.AWS_ACCOUNT_ID }}:listener/app/splanet/${{ secrets.ARN_ID_443 }} \
                --default-actions '[{
                  "Type": "forward",
                  "ForwardConfig": {
                    "TargetGroups": [
                      {"TargetGroupArn": "'"$NEW_TARGET_GROUP_ARN"'", "Weight": '"$TRAFFIC_NEW"'},
                      {"TargetGroupArn": "'"$OLD_TARGET_GROUP_ARN"'", "Weight": '"$TRAFFIC_OLD"'}
                    ]
                  }
                }]'
              sleep 5
            done

      - name: Stop Current Version
        uses: appleboy/ssh-action@v0.1.6
        with:
          host: ${{ secrets.EC2_HOST }}
          username: ubuntu
          key: ${{ secrets.EC2_SSH_KEY }}
          script: |
            CURRENT_VERSION=${{ env.CURRENT_VERSION }}
            if [ "$CURRENT_VERSION" != "none" ]; then
              echo "Stopping current version: splanet_$CURRENT_VERSION"
              sudo docker stop splanet_$CURRENT_VERSION
            fi