Public SourceMage Discussion List

["David Brown" <dmlb2000 AT gmail.com>]

=== Background ===
Okay for a few months now I've been working on stage root sorcery.
The idea behind stage root sorcery is to install a package to a stage
root transparently to the package.  Meaning the package doesn't know
it's installing to a stage root location.  Then sorcery can handle
moving the files back into the system or install root.

=== Why It's Needed? ===
This feature will fix several bugs currently open in bugzilla slated
for 1.14. Including fixing shell redirection to create files not being
tracked and proper config file handling.  Also this will allow spells
to not need to implement and use the INSTALL_ROOT variable.  However,
for the time being they will because we plan on supporting turning off
stage root.

=== General Info on Use ===
This feature will only be supported in build api2 spells and there
will be a way for spell gurus to access the staged files before they
are put into the system.  In order to cast using stage root (once I
tell you how to set it up) you have to compile and install, ressurrect
doesn't use it (even though it could I suppose but that may come
later).

=== Spell Access to Stage Root ===
With stage root POST_INSTALL will have a new meaning, POST_INSTALL
will have the sorcery environment and the current working directory
will be at the root of the stage root.  This will allow you to use
POST_INSTALL to check for file permissions move or remove files that
you don't want in the install log for the package.  This means spells
could get really nutty and look like debian packages where there's the
main package then a -dev package that contains all the libs and
headers, and everything will be compile from source.  You can see
further examples in the gcc set of packages in stage_root grimoire.

=== Additions to Manage Stage Root ===
There's two things added for users of stage root, the script confmeld
and the variable STAGED_INSTALL.  Configuration files are
automatically put in a special stage area so they can be merged into
the system by the user.  The script confmeld is there so this can be
accomplished without doing things manually (even though you can
manually everythings in /var/state/sorcery/staged_configs).  The
script is assumed to be called as root user, the code for asking for a
password then recalling itself via su -c isn't in place yet.  The
basic sequence for confmeld is to run find on the directory looking
for regular files then merging them back into the system with
install_config_file.  The variable STAGED_INSTALL is to turn off the
stage root feature when using cast.  To turn things off simply
`STAGED_INSTALL=off cast -c <spell>`. Setting STAGED_INSTALL to "off"
and only "off" will turn off the stage root feature, anything else
will keep stage root on.

=== What I'm Expecting From Alpha Testers ===
Some of the things I'm looking for from alpha testers are as follows:
1) does a cast look okay, try different color configurations?
2) do things like cast with screen still work well? other features
from the feature menu?
3) does confmeld work? does it need additions? look of the output okay?
4) do install logs, md5sum logs, and archives still look okay?

=== How to Set Stage Root Up ===
Follow these instructions in order and you should get stage root
sorcery working.
PRECONDITIONS: You should have test grimoire and devel sorcery
currently running on the system.  It's recommended to use this in a
chroot environment first (simply because I'm not too sure about issues
converting back to normal devel sorcery and test grimoire).
1) Get Stage Root Sorcery:
bzr branch http://scm.sourcemage.org/smgl/sorcery/stage-root
or if Andrew would publish a source tarball somewhere then get that. ;)
2) Install Stage Root Sorcery:
nothing about the install is different from any other version of
sorcery, so if you don't know how to do this you probably shouldn't be
an alpha tester...
3) Get Stage Root Grimoire:
it's in perforce //sgl/grimoires/stage_root
4) make sure stage_root grimoire is above your test grimoire:
so something like this in your /etc/sorcery/local/grimoire file.
GRIMOIRE_DIR[0]=/var/lib/sorcery/codex/stage_root
GRIMOIRE_DIR[1]=/var/lib/sorcery/codex/test
GRIMOIRE_DIR[2]=/var/lib/sorcery/codex/z-rejected
5) Install the New Installwatch
cast -c installwatch
POSTCONDITIONS: gcc and g++ versions will have changed so if you like
you can install the parallel installs of gcc and g++.  However, if you
don't want to do this hold them.  I haven't tested the update from
current install of gcc to parallel so it probably won't be very
smooth.

Thanks a bunch for any comments.

- David Brown