Deploy an Application using zypper

Scope

The purpose of this guide is to deploy an application or the dependencies of an application from rpms into a deployment image using the zypper package manager.

Using zypper’s custom root

Zypper provides the --root flag to install packages into a custom root and not use /. We can leverage this feature to install a package including all of its dependencies into a custom root and then copy this directory into a deployment image. In the following example we install apache2 including all of its dependencies and copy them into the deployment image based on bci-micro:

FROM registry.suse.com/bci/bci-micro:latest AS minimal
FROM registry.suse.com/bci/bci-base:latest AS builder

RUN mkdir -p /chroot/etc/zypp/repos.d/
COPY --from=minimal / /chroot/
RUN cp {,/chroot}/etc/zypp/repos.d/SLE_BCI.repo && \
    zypper --root /chroot -n --gpg-auto-import-keys in --no-recommends apache2 && \
    zypper --root /chroot clean -a && \
    rm -rf /chroot/var/log/

FROM minimal
WORKDIR /
COPY --from=builder /chroot/ /

Customizing zypper’s installation behavior

We can further reduce the final image size by supplying a custom zypper configuration file. We can tweak zypper’s behavior further via that configuration file to e.g. omit the installation of documentation files. To achieve this omission of configuration files, create the following scratch-zypp.conf:

[main]
rpm.install.excludedocs = yes

And modify the Dockerfile as follows:

FROM registry.suse.com/bci/bci-micro:latest AS minimal
FROM registry.suse.com/bci/bci-base:latest AS builder

RUN mkdir -p /chroot/etc/zypp/repos.d/
COPY --from=minimal / /chroot/
COPY scratch-zypp.conf /
ENV ZYPP_CONF=/scratch-zypp.conf
RUN cp {,/chroot}/etc/zypp/repos.d/SLE_BCI.repo && \
    zypper --root /chroot -n --gpg-auto-import-keys in --no-recommends apache2 && \
    zypper --root /chroot clean -a && \
    rm -rf /chroot/var/log/

FROM minimal
WORKDIR /
COPY --from=builder /chroot/ /