Modifying the Installation by an Add-on
The YaST installation workflow can be easily changed or extended by add-ons.
Configuring the Add-on Metadata
The product package on the add-on medium (usually a *-release RPM package)
should link to a package providing the installer extension by a
Provides: installerextension(<package_name>) dependency.
That referenced package should contain the installation.xml file and optionally
the y2update.tgz archive in the root directory. The package should never
be installed into system, it is used just to provide the temporary data for the
installer. After the installation is finished the files are not needed anymore.
Modifying the Installation Workflow
This installation.xml example has two parts:
- The first part adds a new step into the add-on installation workflow in already installed system.
- The second part adds a new step into the initial installation workflow.
<?xml version="1.0"?>
<productDefines xmlns="http://www.suse.com/1.0/yast2ns" xmlns:config="http://www.suse.com/1.0/configns">
<workflows config:type="list">
<!-- Installation on a running system -->
<workflow>
<stage>normal</stage>
<mode>installation,normal</mode>
<defaults>
<enable_back>no</enable_back>
<enable_next>no</enable_next>
</defaults>
<modules config:type="list">
<module>
<label>Extension Configuration</label>
<name>testing_extension</name>
<execute>inst_testing_extension</execute>
<enable_back>yes</enable_back>
<enable_next>yes</enable_next>
</module>
</modules>
</workflow>
</workflows>
<update>
<workflows config:type="list">
<workflow>
<defaults>
<enable_back>yes</enable_back>
<enable_next>yes</enable_next>
</defaults>
<!-- First Stage Installation -->
<stage>initial</stage>
<mode>installation</mode>
<!-- Insert new steps -->
<insert_modules config:type="list">
<insert_module>
<before>system_role</before>
<modules config:type="list">
<module>
<label>Extension Configuration</label>
<name>testing_extension</name>
<!-- Name of the executed file without the .rb extension -->
<execute>inst_testing_extension</execute>
</module>
</modules>
</insert_module>
</insert_modules>
</workflow>
</workflows>
</update>
</productDefines>
Adding a New System Role
This installation.xml example adds a new role:
<?xml version="1.0"?>
<productDefines xmlns="http://www.suse.com/1.0/yast2ns" xmlns:config="http://www.suse.com/1.0/configns">
<update>
<system_roles>
<insert_system_roles config:type="list">
<insert_system_role>
<system_roles config:type="list">
<system_role>
<id>mail_role</id>
<software>
<default_patterns>base Minimal mail_server</default_patterns>
</software>
</system_role>
</system_roles>
</insert_system_role>
</insert_system_roles>
</system_roles>
</update>
<!-- Don't forget to add the texts -->
<texts>
<mail_role>
<label>Testing Extension Role</label>
</mail_role>
<mail_role_description>
<label>• Mail server software pattern
• This is just an example!</label>
</mail_role_description>
</texts>
</productDefines>
In this case it just configures the default software patterns but it is possible to define any other defaults like partitioning, etc...
Adding New YaST Code
The installer extension package can optionally contain y2update.tgz archive
with executable YaST code in the usual directory structure. E.g. the clients are
read from the /usr/share/YaST2/clients directory in the archive.
YaST Client Example
Here is a trivial example client which just displays a pop up dialog with a message:
module Yast
class TestingExtensionClient < Client
include Yast::I18n
def initialize
textdomain "testing-extension"
Yast.import("Popup")
end
def main
# TRANSLATORS: A popup message
Popup.Message(_("This is an inserted step from the testing-extension add-on."\
"\n\nPress OK to continue."))
return :auto
end
end
end
Yast::TestingExtensionClient.new.main
Save this file to usr/share/YaST2/clients/inst_testing_extension.rb file (including
the directory structure) and then create the y2update.tgz archive with command
tar cfzv y2update.tgz usr
and include it in the installer extension RPM package.
An Example Add-on
A minimalistic but complete example add-on can be found in the YaST:extension OBS project.
The testing-extension-release package
links to the installer extension using Provides:
installerextension(testing-extension-installation).
The testing-extension-installation package
contains the installation.xml file which defines an additional role and
adds a new installation step before the role selection dialog. The new installation
step is defined in the included y2update.tgz file.
Modify Installation by Availability of Package
The YaST installation workflow can be easily changed or extended by availability of package that provides certain provisioning. It is useful for modules, which can be added, but does not need to have own product.
Configuring the Package Metadata
The extension package on the medium have to have
Provides: installer_module_extension() = <module name> dependency. Module name is used only
for logging purpose.
The extension package will be available for all products in the medium unless it is stated
otherwise. In order to limit the extension package to a product, it needs to have the
extension_for_product() = <product name> dependency. Multiple products can be specified
by having multiple dependencies, one for every product.
That package should contain the installation.xml file and optionally
the y2update.tgz archive in the root directory. The package should never
be installed into system, it is used just to provide the temporary data for the
installer. After the installation is finished the files are not needed anymore.
Requirements for installation.xml and y2update.tgz is identical like for add-ons.
For example package see https://github.com/yast/skelcd-control-server-applications-module