KDE software is split into different components, many of which can be built by kdesrc-build. Understanding this organization will help you properly select the software modules that you want built.

Selecting which of the possible modules to build is controlled by the configuration file. After the global section is a list of modules to build, bracketed by module ... end module lines. An example entry for a module is shown in Example 2.4, “Example module entry in the configuration file”.

module kdesrc-build-git
    # Options for this module go here, example:
    repository kde:kdesrc-build
    make-options -j4 # Run 4 compiles at a time
end module

When using only module entries, kdesrc-build builds them in the order you list, and does not attempt to download any other repositories other than what you specify directly.

The KDE source code is decomposed into a great number of relatively small Git-based repositories. To make it easier to manage the large number of repositories involved in any useful KDE-based install, kdesrc-build supports grouping multiple modules and treating the group as a “module set”.

global
    git-repository-base kde-git kde:
end global

module qt
    # Options removed for brevity
end module

module-set kde-support-libs
    repository kde-git
    use-modules automoc attica akonadi
end module-set

# Other modules as necessary...
module kdesupport
end module

# Only adds a module for juk (the kde/kdemultimedia/juk repo)
module-set juk-set
    repository kde-projects
    use-modules juk
end module-set

# Adds all modules that are in kde/multimedia/*, including juk,
# but no other dependencies
module-set multimedia-set
    repository kde-projects
    use-modules kde/multimedia
end module-set

# Adds all modules that are in kde/multimedia/*, and all kde-projects
# dependencies from outside of kde/kdemultimedia
module-set multimedia-deps-set
    repository kde-projects
    use-modules kde/multimedia
    include-dependencies true
end module-set

# All modules created out of these three module sets are automatically put in
# proper dependency order, regardless of the setting for include-dependencies

KDE's Git repositories allow for grouping related Git modules into collections of related modules (e.g. kdegraphics). Git doesn't recognize these groupings, but kdesrc-build can understand these groups, using module sets with a repository option set to “kde-projects”.

kdesrc-build will recognize that the kde-projects repository requires special handling, and adjust the build process appropriately. Among other things, kdesrc-build will:

The following example shows how to use the KDE module database to install the Phonon multimedia library.

module-set media-support
    # This option must be kde-projects to use the module database.
    repository kde-projects

    # This option chooses what modules to look for in the database.
    use-modules phonon/phonon phonon-gstreamer phonon-vlc
end module-set

The following example is perhaps more realistic, and shows a feature only available with the KDE module database: Building all of the KDE graphics applications with only a single declaration.

module-set kdegraphics
    # This option must be kde-projects to use the module database.
    repository kde-projects

    # This option chooses what modules to look for in the database.
    use-modules kdegraphics/libs kdegraphics/*
end module-set

There are two important abilities demonstrated here:

You might decide that you'd like to build all programs within a KDE module grouping except for a given program.

For instance, the kdeutils group includes a program named kremotecontrol. If your computer does not have the proper hardware to receive the signals sent by remote controls then you may decide that you'd rather not download, build, and install kremotecontrol every time you update kdeutils.

You can achieve this by using the ignore-modules configuration option. On the command line the --ignore-modules option does the same thing, but is more convenient for filtering out a module just once.

module-set utils
    repository kde-projects

    # This option chooses what modules to look for in the database.
    use-modules kdeutils

    # This option "subtracts out" modules from the modules chosen by use-modules, above.
    ignore-modules kremotecontrol
end module-set

module-set graphics
    repository kde-projects

    # This option chooses what modules to look for in the database.
    use-modules extragear/graphics

    # This option "subtracts out" modules from the modules chosen by use-modules, above.
    # In this case, *both* extragear/graphics/kipi-plugins and
    # extragear/graphics/kipi-plugins/kipi-plugins-docs are ignored
    ignore-modules extragear/graphics/kipi-plugins
end module-set