In correlation with the end of life (EOL) for MKE 3.3.x, maintenance of this documentation set was discontinued as of 2022-MAY-27. Click here for the latest MKE 3.x version documentation.

Deploy a multi-service application

This topic describes how to use both the MKE web UI and the CLI to deploy a multi-service application for voting on whether you prefer cats or dogs.


To deploy a multi-service application using the MKE web UI:

  1. Log in to the MKE web UI.

  2. Navigate to Shared Resources > Stacks and click Create Stack.

  3. In the Name field, enter voting-app.

  4. Under ORCHESTRATOR MODE, select Swarm Services and click Next.

  5. In the Add Application File editor, paste the following application definition written in the docker-compose.yml format:

    version: "3"
services:

  # A Redis key-value store to serve as message queue
  redis:
    image: redis:alpine
    ports:
      - "6379"
    networks:
      - frontend

  # A PostgreSQL database for persistent storage
  db:
    image: postgres:9.4
    volumes:
      - db-data:/var/lib/postgresql/data
    networks:
      - backend

  # Web UI for voting
  vote:
    image: dockersamples/examplevotingapp_vote:before
    ports:
      - 5000:80
    networks:
      - frontend
    depends_on:
      - redis

  # Web UI to count voting results
  result:
    image: dockersamples/examplevotingapp_result:before
    ports:
      - 5001:80
    networks:
      - backend
    depends_on:
      - db

  # Worker service to read from message queue
  worker:
    image: dockersamples/examplevotingapp_worker
    networks:
      - frontend
      - backend

networks:
  frontend:
  backend:

volumes:
  db-data:

  6. Click Create to deploy the stack.

  7. In the list on the Shared Resources > Stacks page, verify that the application is deployed by looking for voting-app. If the application is in the list, it is deployed.

  8. To view the individual application services, click voting-app and navigate to the Services tab.

  9. Cast votes by accessing the service on port 5000.

Caution

  • MKE does not support referencing external files when using the MKE web UI to deploy applications, and thus does not support the following keywords:

    • build

    • dockerfile

    • env_file

  • You must use a version control system to store the stack definition used to deploy the stack, as MKE does not store the stack definition.


To deploy a multi-service application using the MKE CLI:

  1. Download and configure the client bundle.

  2. Create a file named docker-stack.yml with the following content:

    version: "3"
services:

  # A Redis key-value store to serve as message queue
  redis:
    image: redis:alpine
    ports:
      - "6379"
    networks:
      - frontend

  # A PostgreSQL database for persistent storage
  db:
    image: postgres:9.4
    volumes:
      - db-data:/var/lib/postgresql/data
    networks:
      - backend

  # Web UI for voting
  vote:
    image: dockersamples/examplevotingapp_vote:before
    ports:
      - 5000:80
    networks:
      - frontend
    depends_on:
      - redis

  # Web UI to count voting results
  result:
    image: dockersamples/examplevotingapp_result:before
    ports:
      - 5001:80
    networks:
      - backend
    depends_on:
      - db

  # Worker service to read from message queue
  worker:
    image: dockersamples/examplevotingapp_worker
    networks:
      - frontend
      - backend

networks:
  frontend:
  backend:

volumes:
  db-data:

  3. Create the application:

    docker stack deploy --compose-file voting-app
  
    docker-compose --file docker-compose.yml --project-name voting-app up -d

  4. Verify that the application is deployed:

    docker stack ps voting-app

  5. Cast votes by accessing the service on port 5000.