Building containers locally

When you have your module built, let’s put it in a container, so we can use it. As an example, we will use the perl image.

Module RPM repository

First, upload your RPM repository from the previous step somewhere publicly accessible. For example, you can use Fedorapeople to host your packages:

$ mkdir module
$ cp $RPMS module/
$ createrepo_c module/
$ rsync ./module/ $USER@fedorapeople.org:public_html/


Next step will be writing a Dockerfile to build a container image with your module.

The Base Runtime image is currently only available from Docker Hub and you can use it as your base image by specifying FROM /baseruntime/baseruntime.

You also need to write a repo file for your module and add it to your container, so you can install the module in it. See the example of the repo file in https://github.com/container-images/perl/tree/master/repos. The following snippet then shows how you copy the repo and install the files from it in your container:

COPY repos/* /etc/yum.repos.d/
# Perl and build tools install + user addition
RUN BUILD_TOOlS="bsdtar \
  findutils \
  gcc \
  make \
  gettext \
  tar \
  wget \
  python " && \
  microdnf --nodocs --enablerepo perl install perl perl-devel && \
  microdnf --nodocs --enablerepo fedora install -y mod_perl cpan cpanminus httpd \
    $BUILD_TOOlS && \
        microdnf clean all
RUN mkdir -p /opt/app-root/src/ && \
    useradd -u 1002 -r -g 0 -d /opt/app-root/src -s /sbin/nologin \
    -c "Default Application User" default && \
    chown -R 1002:0 /opt/app-root

Building the image

Finally, when you have your repository and Dockerfile ready, use the docker build --tag= command to build the container image.