Introduction to Lorax — Lorax 28.14.33 documentation

# Introduction to Lorax

I am the Lorax. I speak for the trees [and images].

Lorax is used to build the Anaconda Installer boot.iso, it consists of a library, pylorax, a set of templates, and the lorax script. Its operation is driven by a customized set of Mako templates that lists the packages to be installed, steps to execute to remove unneeded files, and creation of the iso for all of the supported architectures.

# Before Lorax

Tree building tools such as pungi and revisor rely on ‘buildinstall’ in anaconda/scripts/ to produce the boot images and other such control files in the final tree. The existing buildinstall scripts written in a mix of bash and Python are unmaintainable. Lorax is an attempt to replace them with something more flexible.

EXISTING WORKFLOW:

pungi and other tools call scripts/buildinstall, which in turn call other scripts to do the image building and data generation. Here’s how it currently looks:

> -> buildinstall
>   - process command line options
>   - write temporary yum.conf to point to correct repo
>   - find anaconda release RPM
>   - unpack RPM, pull in those versions of upd-instroot, mk-images, maketreeinfo.py, makestamp.py, and buildinstall

>   -> call upd-instroot

>   -> call maketreeinfo.py

>   -> call mk-images (which figures out which mk-images.ARCH to call)

>   -> call makestamp.py

>   - clean up

PROBLEMS:

The existing workflow presents some problems with maintaining the scripts. First, almost all knowledge of what goes in to the stage 1 and stage 2 images lives in upd-instroot. The mk-images* scripts copy things from the root created by upd-instroot in order to build the stage 1 image, though it’s not completely clear from reading the scripts.

NEW IDEAS:

Create a new central driver with all information living in Python modules. Configuration files will provide the knowledge previously contained in the upd-instroot and mk-images* scripts.