This program serves a dual role; its "tree compose" command is
intended for use on build servers, to take RPM packages and commit
them to an OSTree
repository. On the client side, it acts as a consumer of the
libostree shared library, integrating upgrades with RPM.
The previous major release of this program contained within it an "autobuilder" codebase which had significant functionality beyond just composing trees, such as creating VM disk images and running smoketests.
Since that time, the other functionality has moved to: https://github.com/cgwalters/rpm-ostree-toolbox
This program now only commits trees to a repository, using "treefiles" which are very simple JSON input data.
First, unfortunately you must disable SELinux on the build host in order to support SELinux on the built system. See: https://bugzilla.redhat.com/show_bug.cgi?id=1060423
Once you have that done, choose a build directory. Here we'll use /srv/rpm-ostree.
# cd /srv/rpm-ostree
# mkdir repo
# ostree --repo=repo init --mode=archive-z2
The core "rpm-ostree tree compose" builtin as input a "treefile". See
examples in doc/treefile-examples, as well as doc/treefile.md.
# rpm-ostree compose tree --repo=/srv/rpm-ostree/repo --proxy=http://127.0.0.1:8123 sometreefile.json
All this does is use yum to download RPMs from the referenced repos,
and commit the result to the OSTree repository, using the ref named by
ref. Note that we've specified a local caching proxy (polipo in
this case) - otherwise we you will download the packages for each
treecompose.
You can export /srv/rpm-ostree/repo via any static webserver.
The use of --proxy is not mandatory but strongly recommended - with
this option you can avoid continually redownloading the packages every
compose. I personally use
Polipo,
but you can of course any HTTP proxy you wish.