docker-compose.yaml

# Assignment Requirements
# db must only run on a node with ssd=true label
# vote should be HA with 2 replicas
# vote must not run on Swarm manager nodes
# worker needs to scale with Swarm worker nodes, 1 task each

version: "3.1"
services:
    redis:
        image: redis:alpine
        networks:
            - frontend
    db:
        image: postgres:9.6
        volumes:
            - db-data:/var/lib/postgresql/data
        environment:
            - POSTGRES_HOST_AUTH_METHOD=trust
        networks:
            - backend
        deploy:
            placement:
                constraints:
                    - node.labels.ssd == true
    vote:
        image: bretfisher/examplevotingapp_vote
        ports:
            - '5000:80'
        networks:
            - frontend
        deploy:
            replicas: 2
            placement:
                constraints:
                    - node.role == worker
            
    result:
        image: bretfisher/examplevotingapp_result
        ports:
            - '5001:80'
        networks:
            - backend
    worker:
        image: bretfisher/examplevotingapp_worker:java
        networks:
            - frontend
            - backend
        deploy:
            mode: global
            placement:
                constraints:
                    - node.role == worker
networks:
    frontend: null
    backend: null
volumes:
    db-data: null