3-Tier Java (ApacheLB-Tomcat-PostgreSQL-Cluster-REX-Ray)

HTTP-LB:
  image: httpd:latest
  publish_all: true
  mem_min: 50m
  host: host1
  plugins:
    - !plugin
      id: uazUi
      restart: true
      lifecycle: on_create, post_scale_out:AppServer, post_scale_in:AppServer
      arguments:
        # Use container_private_ip if you're using Docker networking
        #- BalancerMembers=BalancerMember http://{{AppServer | container_private_ip}}:8080
        # Use container_hostname if you're using Weave networking
        - BalancerMembers=BalancerMember http://{{AppServer | container_hostname}}:8080
AppServer:
  image: tomcat:8.0.21-jre8
  mem_min: 600m
  host: host1
  cluster_size: 1
  environment:
    - database_driverClassName=org.postgresql.Driver
    # Use this configuration with Docker networking
    #- database_url=jdbc:postgresql://{{postgres_master|container_private_ip}}:5432/{{postgres_master|DB_NAME}}
    # Use this configuration with Weave
    - database_url=jdbc:postgresql://{{postgres_master|container_hostname}}:5432/{{postgres_master|DB_NAME}}
    - database_username={{postgres_master|DB_USER}}
    - database_password={{postgres_master|DB_PASS}}
  plugins:
    - !plugin
      id: oncXN
      restart: true
      arguments:
        - file_url=https://github.com/dchqinc/dchq-docker-java-example/raw/master/dbconnect.war
        - dir=/usr/local/tomcat/webapps/ROOT.war
        - delete_dir=/usr/local/tomcat/webapps/ROOT
postgres_master:
  restart: always
  host: host2
  #ports:
  #  - 5432:5432
  image: dchq/postgres:latest
  environment:
    - DEBUG=false
    - DB_USER=root
    - DB_PASS={{alphanumeric | 8}}
    - DB_NAME=names
    - DB_UNACCENT=false
    - REPLICATION_MODE=master
    - REPLICATION_USER=replicator
    - REPLICATION_PASS={{alphanumeric | 8}}
  volumes:
    - "/var/lib/rexray/volumes/dchq-postgres-master/data:/var/lib/postgresql"
  plugins:
    - !plugin
     # Only mounts volume
     #id: CmA35
     # Create and mount volume
     id: 8CF1C
     lifecycle: exec_on_machine pre_create
     arguments:
       - VOLUME_NAME=dchq-postgres-master
       - VOLUME_SIZE=5
    #  Nightly snapshot
    #- !plugin
    #  id: dE4qG
    #  lifecycle: exec_on_machine cron(0 1 1 * * ?)
    #  arguments:
    #   - VOLUME_NAME=dchq-postgres-master
postgres_slave:
  restart: always
  host: host3
  #ports:
  #  - 5432:5432
  image: dchq/postgres:latest
  environment:
    - DEBUG=false
    - REPLICATION_MODE=slave
    # Use this configuration with Docker networking
    #- REPLICATION_HOST={{postgres_master | container_private_ip}}
    # Use this configuration with Weave
    - REPLICATION_HOST={{postgres_master | container_hostname}}
    - REPLICATION_USER={{postgres_master | REPLICATION_USER}}
    - REPLICATION_PASS={{postgres_master | REPLICATION_PASS}}
    - REPLICATION_PORT=5432
  volumes:
    - "/var/lib/rexray/volumes/dchq-postgres-slave/data:/var/lib/postgresql"
  plugins:
    - !plugin
     # Only mounts volume
     #id: CmA35
     # Create and mount volume
     id: 8CF1C
     lifecycle: exec_on_machine pre_create
     arguments:
       - VOLUME_NAME=dchq-postgres-slave
       - VOLUME_SIZE=5
    #  Nightly snapshot
    #- !plugin
    #  id: dE4qG
    #  lifecycle: exec_on_machine cron(0 1 1 * * ?)
    #  arguments:
    #   - VOLUME_NAME=dchq-postgres-master