| 1 |
[[!meta title="DEP-6: Meta-Package debian/control field"]]
|
| 2 |
|
| 3 |
Title: Meta-Package debian/control field
|
| 4 |
DEP: 6
|
| 5 |
State: DRAFT
|
| 6 |
Date: 2009-12-20
|
| 7 |
Drivers: David Paleino <dapal@debian.org>, Luca Bruno <lethalman88@gmail.com>
|
| 8 |
URL: http://dep.debian.net/deps/dep6
|
| 9 |
License:
|
| 10 |
Copying and distribution of this file, with or without modification,
|
| 11 |
are permitted in any medium without royalty provided the copyright
|
| 12 |
notice and this notice are preserved.
|
| 13 |
Abstract:
|
| 14 |
Introduce the usage of a new field in debian/control, Meta-Package,
|
| 15 |
to mark "meta-packages" as such, and allow easy choice of
|
| 16 |
installed packages, without being bitten by the "autoremove"
|
| 17 |
feature of package management tools.
|
| 18 |
|
| 19 |
[[!toc ]]
|
| 20 |
|
| 21 |
Introduction
|
| 22 |
------------
|
| 23 |
This document proposes a new field for debian/control, to be used in
|
| 24 |
the so-called "meta-packages". A meta-package is a package which does
|
| 25 |
not contain any files to be installed. Instead it has dependencies to
|
| 26 |
other packages. There are several uses for metapackages, for example
|
| 27 |
to provide a Desktop Environment with some default applications
|
| 28 |
installed.
|
| 29 |
|
| 30 |
Rationale
|
| 31 |
---------
|
| 32 |
With the *autoremove* command being now widely used, it can become
|
| 33 |
difficult for a user to install a meta-package except for some packages it
|
| 34 |
depends on.
|
| 35 |
|
| 36 |
In fact, when removing any dependency of the meta-package, it gets
|
| 37 |
removed as well, and all other dependencies become *leaf packages* that
|
| 38 |
autoremove will try to remove from the system. This is usually not
|
| 39 |
what the users want, as they probably installed (or had it by default)
|
| 40 |
the meta-package to have a "standard" environment, but don't want or
|
| 41 |
need specific packages.
|
| 42 |
|
| 43 |
With the current situation, the only solution is to specify as
|
| 44 |
*manually installed* the packages the users want to keep on their
|
| 45 |
systems.
|
| 46 |
|
| 47 |
This document thus tries to introduce a new mechanism for
|
| 48 |
meta-packages, which would be marked with **Meta-Package: yes** in the
|
| 49 |
debian/control control file, and whose dependencies removal would not
|
| 50 |
cause the dependant removal. Think of this as a new Recommends field,
|
| 51 |
which cannot be controlled via /etc/apt/preferences (or similar
|
| 52 |
configuration file).
|
| 53 |
|
| 54 |
Backwards Compatibility
|
| 55 |
-----------------------
|
| 56 |
We started thinking about "Meta-Depends" fields, but soon abandoned the
|
| 57 |
idea. This is because this field would break existing package managers
|
| 58 |
which haven't implemented yet this DEP. That's why we chose to keep
|
| 59 |
Depends, and add an extra field, called **Meta-Package**.
|
| 60 |
|
| 61 |
Implementation
|
| 62 |
--------------
|
| 63 |
### Packages ###
|
| 64 |
Meta-packages should use **Meta-Package: yes** in a binary stanza in the
|
| 65 |
*debian/control* file.
|
| 66 |
|
| 67 |
### Package managers ###
|
| 68 |
Package managers, upon removal of any package, should check dependant
|
| 69 |
packages, and act accordingly.
|
| 70 |
|
| 71 |
If any dependant package is a meta-package, as defined by this
|
| 72 |
document, it should **NOT** be removed, opposed to what the current
|
| 73 |
implementations do. The package manager should then add the removed
|
| 74 |
package to a "blacklist" for the dependant meta-package. This allows
|
| 75 |
for upgrades of the meta-package without re-installing everything again,
|
| 76 |
i.e. the package manager should check the dependencies of the
|
| 77 |
meta-package against its blacklist, if present.
|
| 78 |
|
| 79 |
If the Meta-Package field is not present, then the package manager
|
| 80 |
should act normally, without any modification from the current
|
| 81 |
behaviour.
|
| 82 |
|
| 83 |
If the meta-package is removed, all its dependencies are marked for
|
| 84 |
auto-removal, following the current behaviour.
|
| 85 |
|
| 86 |
#### Blacklist management ####
|
| 87 |
Package managers should allow for deletion of the blacklist upon
|
| 88 |
removal of the meta-package.
|
| 89 |
|
| 90 |
Moreover, they should allow the deletion of the blacklist, and the
|
| 91 |
installation of the missing meta-package dependencies at the same time.
|
| 92 |
|
| 93 |
Tools support
|
| 94 |
-------------
|
| 95 |
### apt-get ###
|
| 96 |
None.
|
| 97 |
|
| 98 |
### aptitude ###
|
| 99 |
None.
|
| 100 |
|
| 101 |
### cupt ###
|
| 102 |
None.
|
| 103 |
|
| 104 |
### smart ###
|
| 105 |
None.
|
| 106 |
|
| 107 |
Changes
|
| 108 |
-------
|
| 109 |
|
| 110 |
* 2009-12-20:
|
| 111 |
[ dapal ]
|
| 112 |
* First draft, RFC made on debian-devel
|
Parent Directory
| 
Revision Log