config.yml

version: 2.1
orbs: 
  slack: circleci/slack@4.10.1

commands:
  destroy-environment:
    description: Destroy back-end and front-end cloudformation stacks given a workflow ID.
    parameters:
      workflow_id:
        type: string
    steps:
      - run:
          name: Destroy front-end cloudformation stack
          when: on_fail
          command: |
            aws cloudformation delete-stack --stack-name udapeople-frontend-<<parameters.workflow_id>>
            # Delete files uploaded from the s3 bucket.
            aws s3 rm s3://udapeople-<<parameters.workflow_id>> --recursive
      - run:
          name: Destroy back-end cloudformation stack
          when: on_fail
          command: |
            aws cloudformation delete-stack --stack-name udapeople-backend-<<parameters.workflow_id>>
  # Rollback any migrations that were successfully applied.
  revert-migrations:
    description: Revert migrations that were successfully applied.
    parameters:
      workflow_id:
        type: string
    steps:
      - run:
          name: Revert migrations
          when: on_fail
          command: |
            # Get kvdb url
            SUCCESS=$(curl --insecure https://kvdb.io/McQbGiQSmDSEvKJhVqyfcn/migration_<<parameters.workflow_id>>)
            # Logic for reverting the database state
            if (($SUCCESS == 1)); then
              echo "Reverting migrations..."
              cd ~/project/backend
              npm install
              npm run migrations:revert
            else
              echo "No migrations to revert."
            fi

jobs:
  # BUILD PHASE
  build-frontend:
    docker:
      - image: circleci/node:13.8.0
    steps:
      - checkout
      - restore_cache:
          keys: [frontend-build]
      - run:
          name: Build front-end
          # NOTE Code to build/compile the frontend
          command: |
            cd frontend
            npm install
            npm run build
      - save_cache:
          paths: [frontend/node_modules]
          key: frontend-build
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1

  build-backend:
    docker:
      - image: circleci/node:13.8.0
    steps:
      - checkout
      - restore_cache:
          keys: [backend-build]
      - run:
          name: Back-end build
          # NOTE Code to build/compile the backend
          command: |
            cd backend
            npm install
            npm run build
      - save_cache:
          paths: [backend/node_modules]
          key: backend-build
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1
  
  #TEST PHASE
  test-frontend:
    docker:
      - image: circleci/node:13.8.0
    steps:
      - checkout
      - restore_cache:
          keys: [frontend-build]
      - run:
          name: Test front-end
          # NOTE Code to test the frontend
          command: |
            cd frontend
            npm install
            npm run test
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1

  test-backend:
    docker:
      - image: circleci/node:13.8.0
    steps:
      - checkout
      - restore_cache:
          keys: [backend-build]
      - run:
          name: Test back-end
          # NOTE Code to test the backend
          command: |
            cd backend
            npm install
            npm run test
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1
          
  #ANALYZE PHASE
  scan-frontend:
    docker:
      - image: circleci/node:13.8.0
    steps:
      - checkout
      - restore_cache:
          keys: [frontend-build]
      - run:
          name: Scan front-end
          # NOTE Code to scan the frontend
          command: |
            cd frontend
            npm install
            npm audit fix --audit-level=critical
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1
  
  scan-backend:
    docker:
      - image: circleci/node:13.8.0
    steps:
      - checkout
      - restore_cache:
          keys: [backend-build]
      - run:
          name: Scan back-end
          # NOTE Code to scan the backend
          command: |
            cd backend
            npm install
            npm audit fix --audit-level=critical
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1

  #INFRASTRUCTURE PHASE
  deploy-infrastructure:
    docker:
      - image: amazon/aws-cli
    steps:
      - checkout
      - run: yum install -y tar gzip
      - attach_workspace:
          at: ~/
      - run:
          name: Ensure back-end infrastructure exists
          command: |
            aws cloudformation deploy \
              --template-file .circleci/files/backend.yml \
              --stack-name "udapeople-backend-${CIRCLE_WORKFLOW_ID:0:7}" \
              --parameter-overrides ID="${CIRCLE_WORKFLOW_ID:0:7}"  \
              --tags project=udapeople
      - run:
          name: Ensure front-end infrastructure exists
          command: |
            aws cloudformation deploy \
              --template-file .circleci/files/frontend.yml \
              --stack-name "udapeople-frontend-${CIRCLE_WORKFLOW_ID:0:7}" \
              --parameter-overrides ID="${CIRCLE_WORKFLOW_ID:0:7}"  \
              --tags project=udapeople
      - run:
          name: Add back-end ip to ansible inventory
          # Fetch the public IP of the EC2 instance and append it to the inventory
          command: |
            export BACKEND_IP=$(aws ec2 describe-instances \
              --filters "Name=tag:project,Values=udapeople" \
              --query "Reservations[*].Instances[*].PublicIpAddress" \
              --output text)
            echo ${BACKEND_IP} > .circleci/ansible/inventory.txt
      - persist_to_workspace:
          root: ~/
          paths:
            - project/.circleci/ansible/inventory.txt  
      - destroy-environment:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1

  configure-infrastructure:
    docker:
      - image: python:3.7-alpine3.11
    steps:
      - checkout
      - add_ssh_keys:
          fingerprints: $FINGERPRINT_ID
      - attach_workspace:
          at: ~/
      - run:
          name: Install dependencies
          working_directory: ./.circleci/ansible
          command: |
            apk add --update ansible
      - run:
          name: Configure server
          command: |
            cd .circleci/ansible
            cat inventory.txt
            ansible-playbook -i inventory.txt configure-server.yml
      - destroy-environment:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1

  # DEPLOY PHASE
  run-migrations:
    docker:
      - image: circleci/node:13.8.0
    steps:
      - checkout
      - restore_cache:
          keys: [backend-build]
      # Run database migrationss
      - run:
          name: Run database migrations
          command: |
            cd backend
            npm install
            npm run migrations > migrations_dump.txt
            cat migrations_dump.txt
      # Send migration status to kvdb.io
      - run:
          name: Send migration status to kvdb.io
          command: |
            if grep -q "has been executed successfully." ~/project/backend/migrations_dump.txt;
            then
              curl https://kvdb.io/McQbGiQSmDSEvKJhVqyfcn/migration_${CIRCLE_WORKFLOW_ID:0:7}  -d '1'
            fi
      - destroy-environment:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1
      
  deploy-frontend:
    docker:
      - image: circleci/node:13.8.0
    steps:
      - checkout
      - attach_workspace:
          at: ~/
      - run:
          name: Install AWS CLI dependencies
          command: |
            sudo apt-get update && sudo apt-get install -yy less
            curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"
            unzip awscliv2.zip
            sudo ./aws/install
      # Get backend url
      - run:
          name: Get backend url
          command: |
            export BACKEND_IP=$(aws ec2 describe-instances \
              --filters "Name=tag:project,Values=udapeople" \
              --query "Reservations[*].Instances[*].PublicIpAddress" \
              --output text)
            export API_URL="http://${BACKEND_IP}:3030"
            echo "API_URL = ${API_URL}"
            echo API_URL="http://${BACKEND_IP}:3030" > frontend/.env
            cat frontend/.env
      # Deploy frontend objects
      - run:
          name: Deploy frontend objects
          command: |
            cd frontend
            npm install
            npm run build
            tar -czvf artifact-"${CIRCLE_WORKFLOW_ID:0:7}".tar.gz dist
            aws s3 cp dist s3://udapeople-${CIRCLE_WORKFLOW_ID:0:7} --recursive
      - destroy-environment:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1
      - revert-migrations:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}


  deploy-backend:
    docker:
      - image: python:3.7-alpine3.11
    steps:
      - checkout
      - add_ssh_keys:
          fingerprints: ["c5:81:c8:a1:27:13:98:b6:e6:67:c7:df:3d:29:83:37"]
      - attach_workspace:
          at: ~/
      - run:
          name: Install zip
          command: |
            apk add --update zip unzip
      # install curl
      - run:
          name: Install curl
          command: |
            apk add --update curl
      - run:
          name: Install ansible
          working_directory: ./.circleci/ansible
          command: |
            apk add --update ansible 
      - run:
          name: Install aws cli
          command: |
            pip install awscli
      - run:
          name: Install nodejs
          command: |
            apk add --update nodejs
      - run:
          name: Install npm
          command: |
            apk add --update npm openssh rsync
      - run:
          name: Deploy backend
          command: |
            mkdir -p .circleci/ansible/roles/deploy/files
            cd backend
            npm i
            npm run build
            cp ~/project/backend/package.json ~/project/backend/dist
            # Zip the directory
            cd ~/project/backend/dist
            zip -rq dist.zip *
            mv dist.zip ~/project/.circleci/ansible/roles/deploy/files/

            cd ~/project/.circleci/ansible
            echo "Contents of the inventory.txt file is ......."
            cat inventory.txt
            ansible-playbook -i inventory.txt deploy-backend.yml
      - destroy-environment:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1
      - revert-migrations:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}

  # SMOKETEST PHASE
  smoke-test:
    docker:
      - image: python:3.7-alpine3.11
    steps:
      - checkout
      - attach_workspace:
          at: ~/
      # Install dependencies like curl, nodejs, npm, awscli
      - run:
          name: Install curl
          command: |
            apk add --update curl
      - run:
          name: Install nodejs
          command: |
            apk add --update nodejs
      - run:
          name: Install npm
          command: |
            apk add --update npm
      - run:
          name: Install aws cli
          command: |
            pip install awscli
      - run:
          name: Run backend smoketests
          command: |
            # Fetch and prepare BACKEND_IP env var
            export BACKEND_IP=$(aws ec2 describe-instances \
              --filters "Name=tag:project,Values=udapeople" \
              --query "Reservations[*].Instances[*].PublicIpAddress" \
              --output text)
            export API_URL="http://${BACKEND_IP}:3030"
            echo "${API_URL}"
            if curl "${API_URL}/api/status" | grep "ok"
            then
              echo "Backend is up and running"
              return 0
            else
              echo "Backend is not running"
              return 1
            fi
      - run:
          name: Run frontend smoketests
          command: |
            # Fetch and prepare FRONTEND_IP env var
            export FRONTEND_URL="http://udapeople-${CIRCLE_WORKFLOW_ID:0:7}.s3-website-us-east-1.amazonaws.com/#/employees"
            echo "${FRONTEND_URL}"
            if curl -s ${FRONTEND_URL} | grep "Welcome"
            then
              echo "Frontend is up and running"
              return 0
            else
              echo "Frontend is not running"
              return 1
            fi
      - destroy-environment:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}
      - revert-migrations:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}

  # Promotion phase
  cloudfront-update:
    docker:
      - image: amazon/aws-cli
    steps:
      - checkout
      - add_ssh_keys:
          fingerprints: ["c5:81:c8:a1:27:13:98:b6:e6:67:c7:df:3d:29:83:37"]
      - run: yum install -y tar gzip
      - attach_workspace:
          at: ~/
      - run:
          name: Get old stack workflow id
          command: |
            # Fetch the old stack workflow id
            export OLD_WORKFLOW_ID=$(aws cloudformation \
              list-exports --query "Exports[?Name==\`WorkflowID\`].Value" \
              --no-paginate --output text)
      - run:
          name: Update cloudfront distribution
          command: |
            aws cloudformation deploy --template-file .circleci/files/cloudfront.yml \
            --stack-name InitialStack \
            --parameter-overrides WorkflowID="${CIRCLE_WORKFLOW_ID:0:7}" \
            --tags project=udapeople
            echo "Cloudfront distribution updated"
      - destroy-environment:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}
      - slack/notify:
          channel: $SLACK_DEFAULT_CHANNEL
          event: fail
          template: basic_fail_1
      - revert-migrations:
          workflow_id: ${CIRCLE_WORKFLOW_ID:0:7}
  
  # Cleanup phase
  cleanup:
    docker:
      - image: amazon/aws-cli
    steps:
      - checkout
      - run:
          name: Get old stack workflow id
          command: |
            # Fetch the old stack workflow id
            export OLD_WORKFLOW_ID=$(aws cloudformation \
              list-exports --query "Exports[?Name==\`WorkflowID\`].Value" \
              --no-paginate --output text)
            # Fetch the stack names
            export STACKS=($(aws cloudformation list-stacks --query "StackSummaries[*].StackName" \
            --stack-status-filter CREATE_COMPLETE --no-paginate --output text))
            echo "Stack names are ${STACKS[@]}"

            # Condition to remove stacks/s3 bucket
            if [[ "${OLD_WORKFLOW_ID}" =~ "${STACKS[@]}"  ]]
            then
              echo "Removing stacks/s3 bucket"
              # Remove stacks
              aws s3 rm "s3://udapeople-${OLD_WORKFLOW_ID}" --recursive
              aws cloudformation delete-stack --stack-name "udapeople-backend-${OLD_WORKFLOW_ID}"
              aws cloudformation delete-stack --stack-name "udapeople-frontend-${OLD_WORKFLOW_ID}"
            fi

# Workflows
workflows:
  default:
    jobs:
      - build-frontend
      - build-backend
      - test-frontend:
          requires: [build-frontend]
      - test-backend:
          requires: [build-backend]
      - scan-frontend:
          requires: [build-frontend]
      - scan-backend:
          requires: [build-backend]
      - deploy-infrastructure:
          requires: [test-frontend, test-backend, scan-frontend, scan-backend]
      - configure-infrastructure:
          requires: [deploy-infrastructure]
      - run-migrations:
          requires: [configure-infrastructure]
      - deploy-frontend:
          requires: [run-migrations]
      - deploy-backend:
          requires: [run-migrations]
      - smoke-test:
          requires: [deploy-frontend, deploy-backend]
      - cloudfront-update:
          requires: [smoke-test]
      - cleanup:
          requires: [cloudfront-update]