- name: Start Docker
  docker_container:
    name: postgres
    image: "centos/postgresql-94-centos7"
    state: started
    recreate: yes
    pull: yes
    env:
      POSTGRESQL_USER: "test"
      POSTGRESQL_PASSWORD: "test"
      POSTGRESQL_DATABASE: "test"
      POSTGRESQL_MAX_CONNECTIONS: 100
      POSTGRESQL_SHARED_BUFFERS: 32M
    exposed_ports:
      - 5432
    ports:
      - 5432:5432
  become: yes
  become_method: sudo

$ sudo docker run --name postgres -e POSTGRESQL_USER="test" -p 5432:5432 centos/postgresql-94-centos7
You must either specify the following environment variables:
  POSTGRESQL_USER (regex: '^[a-zA-Z_][a-zA-Z0-9_]*$')
  POSTGRESQL_PASSWORD (regex: '^[a-zA-Z0-9_~!@#$%^&*()-=<>,.?;:|]+$')
  POSTGRESQL_DATABASE (regex: '^[a-zA-Z_][a-zA-Z0-9_]*$')
Or the following environment variable:
  POSTGRESQL_ADMIN_PASSWORD (regex: '^[a-zA-Z0-9_~!@#$%^&*()-=<>,.?;:|]+$')
Or both.
Optional settings:
  POSTGRESQL_MAX_CONNECTIONS (default: 100)
  POSTGRESQL_MAX_PREPARED_TRANSACTIONS (default: 0)
  POSTGRESQL_SHARED_BUFFERS (default: 32MB)

For more information see /usr/share/container-scripts/postgresql/README.md
within the container or visit https://github.com/openshift/postgresql.