The Installer is written in Java. It presented to the end user via an ant script with three "targets":
install – This is used to install and update (calls install-nocopy).
install-nocopy – Used primarily on Windows but available on all platforms. It does an install or upgrade on a "populated" build environment (calls build-war)
build-war – Rebuilds the war file for an existing install.
The ant script combines these appropriately
These targets prompt for user input, with it being possible to use properties to provide values - ultimately allowing for an unattended install.
However it is quite possible to write Java code control the installation operation.
Extending the Installer Programmatically
NOTE than in V5 it will no longer be possible to programatically extend the Installer.
Property driven installs will still be supported.
The main point of extension is the
InstallerProperties interface and the concrete (and extendable) InstallerPropertiesImpl class. This encapsulates everything about the install and the shipped implementation consults properties or the user in the same way that the current ant based build does. It is extremely likely that InstallerProperties will be extended during the life of V4 with suitable default methods. For instance slip-streaming in a case such as would be done this way. https://shibboleth.atlassian.net/browse/IDP-553 Installation classes
The classes which do the work of the install are
nstall-nocopy target implemented by calling
V4Install and then
install target is implemented by calling all three.
These are also API classes, but they are "locked down" and not suitable for extension:
The idea is that these functions may be called, but not extended. This gives us room to make more changes to their implementation during the life of V4.
The support classes are not intended for extension without the Shibboleth project and are all marked final. Where made possible by the rest of our code base their methods are marked protected. The classes are:
CurrentInstallState - encapsulates the state of the install when the installation started InstallerSupport - some widely used helper functions PropertiesWithComments - allows manipulation of property files during install (and occasionally during upgrade). The main feature is comment-respecting property replacement and property rename.
V4Install class also has a method
MetadataGenerator is a public interface with three methods
setOutput(@Nonnull File where) which sets where the file is to be generated.
what) which sets the parameters from which the metadata may be generated
generate() to write the metadata file
setMetadataGenerator method is defaulted suitably.
The installation process will call initialize on any injected MetadataGenerator
after setting the output and the parameters.
You can implement your own metadata generation by implementing a
MetadataGenerator and installing it appropriately. Property-Driven Install PropertyDrivenInstallation is an easier way to affect much if the installation behavior.