Dockerfile

FROM oraclelinux:7-slim
LABEL maintainer="Sebastian Gumprich"

# Add Oracle EPEL repo that contains Ansible
RUN yum-config-manager --add-repo=http://yum.oracle.com/repo/OracleLinux/OL7/developer_EPEL/x86_64/

# Install Ansible and other requirements.
RUN yum makecache fast \
 && yum -y update \
 && yum -y install --enablerepo=* \
      sudo \
      which \
      ansible \
      systemd \
 && yum clean all  --enablerepo=* \
 && rm -rf /var/cache/yum

# Disable requiretty.
RUN sed -i -e 's/^\(Defaults\s*requiretty\)/#--- \1/'  /etc/sudoers

# Install Ansible inventory file.
RUN echo -e '[local]\nlocalhost ansible_connection=local' > /etc/ansible/hosts

# https://molecule.readthedocs.io/en/latest/examples.html#docker-with-non-privileged-user
# Create `ansible` user with sudo permissions and membership in `DEPLOY_GROUP`
# This template gets rendered using `loop: "{{ molecule_yml.platforms }}"`, so
# each `item` is an element of platforms list from the molecule.yml file for this scenario.
ENV ANSIBLE_USER=ansible DEPLOY_GROUP=deployer SUDO_GROUP=wheel
RUN set -xe \
  && groupadd -r ${ANSIBLE_USER} \
  && groupadd -r ${DEPLOY_GROUP} \
  && useradd -m -g ${ANSIBLE_USER} ${ANSIBLE_USER} \
  && usermod -aG ${SUDO_GROUP} ${ANSIBLE_USER} \
  && usermod -aG ${DEPLOY_GROUP} ${ANSIBLE_USER} \
  && sed -i "/^%${SUDO_GROUP}/s/ALL\$/NOPASSWD:ALL/g" /etc/sudoers

# delete file created by systemd that prevents login via ssh
RUN rm -f /{var/run,etc,run}/nologin

VOLUME ["/sys/fs/cgroup"]
CMD [ "ansible-playbook", "--version" ]