Re: bundles

On Mon, 2004-09-13 at 09:27, Lukas Smith wrote: > Let me brainstorm some related topics. Currently we have alot of > packages that support different backends, optional security improvements > etc. Especially for the different (database) backends alot of packages > already support 3 difference abstraction layers and usually users only > want one. So for that users will eventually be able to select what they > want at install time. Now the question is if we want to enable users to > set those selections globally similar to how gentoo allows you to. So > setting the global option "DB" would set the "only install the DB > backend if relevant" for every package being installed. There is a "provides feature" thingie in package.xml that can be used to express meta-functionality. The idea is stolen^Wborrowed from rpm, where you can specify a dependency like "this package needs a web server", rather than "this package needs apache". For example, you have a package that requires _some_ template package. It has support for a bunch, but it requires at least one of them to be installed. I never got around to implementing this fully, but the idea is this: <deps> <dep type="feature" name="template-system"/> <dep type="pkg" optional="yes" name="HTML_Template_IT"/> <dep type="pkg" optional="yes" name="HTML_Template_Flexy"/> <dep type="pkg" optional="yes" name="HTML_Template_Foobar"/> </deps> This requires that all of the template packages package.xml file contains: <provides type="feature" name="template-system"/> It also requires some discipline in naming features, that'd have to go into some standard or registration process. This way, the list of dependencies above defines a set of options for some type of functionality. For PHP 5 it's logical to add an "interface" dependency/provides option, so you can do: <deps> <dep type="interface">Template</dep> </deps> Since the interface is well-defined, you don't need to specify which implementations are supported like in the first example. The pear server would know which package(s) provide which interfaces. - Stig