NAME
Emdebian::Grip - internal Emdebian module for Emdebian Grip
repositories
Description
It is worthwhile being familiar with "reprepro" (1) when working with
this module.
Emdebian::Grip provides repository management support for the
em_autogrip scripting to manage a three-way repository hierarchy for
Emdebian Grip, including support for migrating packages from unstable
into testing.
Considering just "unstable" initially, the hierarchy is as follows:
Debian unstable is filtered using ${base}${filter_name}/conf/pkglist
which in turn is based on the output of dpkg --get-selections. Only
packages that are actually installed on machines running Emdebian Grip
get added to the pkglist. "reprepro" then updates ${filter_name} from
the chosen Debian mirror, downloading only the binary and source
packages specified in pkglist, to create a partial local mirror for the
list of supported architectures.
Grip unstable is built from the filtered mirror by a combined process
of converting the source package and then identifying the missing
binary packages from the pkglist. During the "emgrip" process, Emdebian
TDebs are created which get included into the locale repository:
Locale is a very specialised repository that is designed for Debian
source packages and Emdebian TDebs only, organised by locale root.
e.g. en_GB support is in the en component. Whereas Debian has three
components (main, contrib and non-free), the locale repository has
ninety seven components (including main for the source packages). In
the locale pool, packages are organised by component so whereas in the
filter or grip repository, "apt" packages are under pool/main/a/apt in
the locale repository the en TDebs for apt are in pool/en/a/apt/ and
the French under pool/fr/a/apt/ etc. The list of locale roots supported
by the locale repository is returned by &get_locale_roots, part of the
"Debian::Packages::Compare" module. For more information on locale
roots as components see:
<http://www.emdebian.org/emdebian/langupdate.html>
As far as testing is concerned, the hierarchy works in a similar way to
Debian, but with extra support for repositories that are started after
packages have migrated into Debian testing and a newer version exists
in Debian unstable.
Note that the testing repository data needs to be setup manually in
many cases - editing conf/distributions for each repository. The
current Emdebian conf files will find their way onto the Debian Wiki in
due course.
With a fully populated Debian unstable, Grip unstable and locale
unstable, &grip_britney can then migrate packages into Grip testing
using the criteria implemented in &get_britney_list from
"Debian::Packages::Compare" and the "reprepro copysrc" command. As
most, if not all, Grip repositories will begin at a time when some
packages in Debian have already migrated into testing and had a newer
version uploaded to unstable, "Emdebian::Grip" also includes catch-up
support via &migrate_missing which includes the relevant packages from
Debian testing as if that version had been uploaded directly to Grip
testing (which, in effect, is what is happening).
The emgrip process can take a significant amount of time - think many
hours, not minutes - principally due to the overhead of generating the
TDebs at one per source per locale per architecture. To create a full
unstable and testing set is likely to take a day or more but is mostly
automated.
The problems that remain are related to dependency issues. The &edos
function in "Emdebian::Grip" does have problems trying to calculate the
solution for dependency problems identified by "edos-debcheck" and the
problems become particularly acute if the repository itself is not in
good shape at the start. Therefore, &edos is not run automatically by
the current tools. The repository must be fully up to date and all
relevant packages need to exist in the filter and in Grip before using
&edos support. Initially, use "edos-debcheck" directly to identify
major problems:
edos-debcheck -explain -failures < ${base}${grip_name}/dists/sid/main/binary-i386/Packages
Packages that are NOT AVAILABLE need to be gripped as source or binary
packages as appropriate but care is needed to correctly interpret the
"edos-debcheck" output to identify the correct link in the chain.
Two major problems exist with automating this process, see
"em_autogrip" (1) for specific information, but suffice it to say here
that there exist in Debian unstable, packages that will appear in the
list of NOT AVAILABLE packages where the correct action is to REMOVE
the package that depends on the unavailable package. These issues are
being discussed within Debian.
Copyright and Licence
Copyright (C) 2007-2009 Neil Williams <codehelp@debian.org>
This package is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
Example
use strict;
use warnings;
use Emdebian::Grip;
use Debian::Packages::Compare;
use vars qw/ $filter_name $grip_name $suite $base $verbose
$noskip @archlist @locroots @lines $line %pkg @filter $have
%debianunstable %gripunstable %tdebunstable /;
my $mirror='http://ftp.uk.debian.org/debian'; # default
$filter_name = 'filter';
$grip_name = 'grip';
$suite = "unstable"; # at first
$base = '/opt/reprepro/';
$verbose = 0;
&set_base($base);
&set_repo_names ($filter_name, $grip_name);
my $a = &get_archlist ($suite, $filter_name);
@archlist = (not defined $a or not @$a) ?
qw/i386 amd64 arm armel powerpc mips mipsel/ : @$a;
my $l = &get_locale_roots ($suite, 'locale');
@locroots = (not defined $l or not @$l) ? qw/ af am ang ar as ast az be bg
bn br bs ca cs cy da de dz el en eo es et eu fa fi fr ga gl gu he hi hr
hu hy ia id io is it ja ka kn km ko ku ky lg li lt lv mai mg mi mk ml mn mr
ms nb ne nl nn no ns nso oc or pa pl ps pt rm ro ru rw si sk sl sq sr sv
ta te th tk tl tr tt ug uk ur uz vi wa wo xh yi zh zu / : @$l;
&setup_repos if ( not -f "${base}${filter_name}/conf/pkglist" );
my $debu = &read_packages ('unstable', $filter_name);
my $gripu = &read_packages ('unstable', $grip_name);
my $tdebu = &read_locale ('unstable', 'locale');
%debianunstable = %$debu if (defined $debu);
%gripunstable = %$gripu if (defined $gripu);
%tdebunstable = %$tdebu if (defined $tdebu);
&update_filter;
&update_repo($verbose);
# begin the work.
set_repo_names
Copies the default or user-specified filter and grip repository names
into the internal module.
set_noskip
Copies the user-specified --noskipold option into the internal module
for use when calling reprepro.
set_dry_run
Configures a dry-run where external commands are printed instead of
executed.
print_missing
Outputs the list returned by
"Debian::Package::Compare::get_missing_sources" in a simple format
print_build_deps
Outputs the list returned by
"Debian::Package::Compare::get_missing_builddeps" in a simple format
print_testing_status
Provides a detailed output of the status of the testing repository for
Grip, comparing Debian unstable (filter) against Debian testing
(filter) and identifying which source packages in Emdebian Grip testing
are behind Debian.
This list is further split into those where the source version in
Debian unstable is precisely the same as the source version in Debian
testing (packages that need to be migrated into Grip testing) and those
where the version in testing differs.
grip_britney
Grip version of the Britney script that migrates packages into Debian
testing. See "Debian::Packages::Compare" (3) for details on
get_britney_list criteria.
In addition, in order to allow new repositories to catch up with
Debian, packages in Grip unstable that are already ahead of Debian
testing need to be gripped directly from Debian testing.
This can also happen when packages are put directly into testing using
testing-proposed-updates during a release freeze in Debian.
Note that grip_britney only migrates packages where the version in
Debian unstable is the same as the version in Debian testing - i.e.
where a migration has already taken place in Debian. Packages that
arrive in testing via testing-proposed-updates or migrated into testing
before the Grip repository was started and which have a later version
now in unstable, can be migrated using migrate_missing.
If you are running grip_britney and migrate_missing together, run
grip_britney first and reload all the data using read_packages before
attempting to run migrate_missing. See migrate_missing for more
information.
migrate_missing
Corollary of grip_britney that completes the process by including into
testing, packages that have a different version in Debian unstable.
Missing packages in testing are included using grip_source and
grip_binary as if uploaded directly to testing (which, in effect, is
what is happening). This means that migrate_missing will take just as
long to process the package in testing as it did to process the later
version that went into unstable. Depending on the number of packages
affected, migrate_missing can take a lot longer than grip_britney but
it should be needed less often once the repository is complete.
edos
Only a basic framework at this stage, this function needs to eventually
collate the results by architecture and repository and try to present a
solution.
See "em_autogrip" (1) for problems with edos recursion.
In $mode eq ’edos’, simply outputs the check data for each of the
filter and grip repositories.
clean_incoming
Call intermittently during long runs.
cleanup
Only call before exit.
update_filter
Fill in the FilterList so that automatic updates can proceed - without
a filter, the entire archive is added. However, updating takes an
appreciable amount of time, so call only when necessary.
extend_filter
Adds package(s) to the filter list, a space separated list is
acceptable.
update_repo
Once the pkglist filter file is correct, call reprepro to get updated
packages.
incoming_locale
Checks the incoming directory for Emdebian TDebs and includes them into
reprepro.
Until the .tdeb extension is supported, reprepro needs to be persuaded
to allow such files using the "--ignore=extension" option.
Amongst all the expected error messages, some useful output is sent to
"STDERR" by reprepro when handling TDebs so errors are not redirected
to /dev/null.
check_dirs
Check that critical directories in the three-way repository hierarchy
exist and create any that are missing.
setup_repos
Note: When setting up your own repository, remember that including the
Contents: specifier in reprepro costs a lot of time during each and
every operation on the repository. Contents is not enabled by
"setup_repos" and it is strongly recommended that it is not re-enabled
in later changes.
Need to decide whether this will cope with multiple suites or just
enforce suite=unstable.
locale is shared with Crush. It’s not particularly easy to add a new
locale root as the scripts and the repos need to be changed at the same
time.
necessary reprepro data (needs config support): these files need to be
created for reprepro final repos will also need "SignWith: 0x97BB3B58"
except stable which should be signed manually to bridge the security
gap between Grip and Debian.
convert_prefix
Debian repositories use the index character of the source package name
in the path to the package directory beneath the pool in order to
reduce the number of listings per directory to a manageable level. The
exception is source packages beginning with ’"lib"’, because there are
so many that the ’"l"’ section would be too large. Whilst ’"l"’
remains, any source package that begins with ’"lib"’ is put under a
separate set of directories using the first four letters instead of
just ’"l"’, e.g. "libaa" will be found under "pool/main/liba/libaa/"
and "libfoo" under "pool/main/libf/libfoo/" but "limpet" would be under
"pool/main/l/limpet/"
convert_prefix is a quick function to determine the correct prefix
under these rules.
grip_source
Wrapper for emgrip that takes a single Debian source package, grips the
binary package where the source package name matches the binary package
name (due to a hitch in how "reprepro" works), generates any Emdebian
TDebs, includes the unchanged source package into Grip, includes any
gripped binary packages into Grip and includes any generated Emdebian
TDebs into locale.
Once the source package has been processed, runs &clean_incoming.
grip_binary
Wrapper for emgrip that takes a single Debian binary package, and grips
it, generates any Emdebian TDebs, includes the gripped binary package
into Grip and includes any generated Emdebian TDebs into locale.
Once the binary package has been processed, runs &clean_incoming.
Components and Sections
Each binary package belongs to a "Section" that broadly describes the
type of functionality in the package. If a component exists in the
repository with the same name as the "Section", the package will be put
into that component. Additionally, if the package name ends in "-dev"
or the "Section" is devel, the "dev" component is selected. If the
package name ends in "-doc" or the "Section" is "doc", the "doc"
component is selected. If there is no matching component configured for
the Grip repository, "main" is used. Section names themselves are read
from the filter repository - i.e. set by the Debian ftp-master
overrides.
switch_component
Single routine to work out which components should be used for which
sections.
AUTHOR
Neil Williams, "<codehelp@debian.org>"
BUGS
Please report any bugs or feature requests to the Debian Bug Tracking
System using "reportbug emdebian-tools".
Known bugs
(Otherwise known as a ToDo list.)
The status of TDebs in the locale repository needs to be checked before
generating more but this means changes in emgrip too so that tdebs can
be skipped with a command line option. However, in normal operation,
the package is only processed because it is out of date so the TDebs
and other files need to be replaced anyway.
"Architecture: all" are packages being continually reprocessed for
several architectures. Originally this was because the package could
contain translations which would need to be architecture-dependent in
Emdebian. However, TDebs should be being generated only from source
packages and this step probably needs to resolved. "reprepro" correctly
handles such duplication, it is just a bit noisy when handling it and
it adds to the time required by the process as a whole.
Also need a general overview function that summaries all three
repositories.