> I have a way to textually specify system installation. Part of it lists > all the packages installed on the system. The idea is that an any given > time the textual representation if valid. Now, suppose a use edits this > representation and adds one more package to the list. If I am to take > this new representation and install a machine based on it, I would have > no guarantee that it will be stable, because the user might not have > specified all the dependent packages. To prevent this problem, I would > like to provide an interface to the user to modify this textual > representation. When user tell the system that he wants to add one > package, the system might end up adding more to the list (textual > representation of the system configuration) after all the dependencies > are resolved. > > Since yum already does dependency resolution I would like to use it. > Ideally, once the user specified the package he wants to add, > internally, I run "yum -C get_dependency_set <user_package>" and yum > returns, say: > " > <user_package> > <package1_that_user_package_also_needs> > <some_other_required_package> > " > > I would like to run yum from cache, to make it a little faster. The > "get_dependency_set" is, obviously, not implemented yet. > > What is the best way to achieve this? If the community thinks that this > is a worthwhile flag to have, I would write the glue code necessary to > get this flag call yum's internal functions (once I figure out where > these functions are). > > Once other way would be to run "yum install <package> and just parse > yum's output, since it has package information when it asks confirmation > questions. But his seems like a bad way. I'd like for people to be able to use yum this way too. I have been and am still working on the abstraction of dependency resolution via yum so it is more suitably used as a library/module. Right now a lot of it is tied up in the metadata format and letting it help you with resolving deps but overall it's pretty straightforward. Right now with yum 2.0.X I'd say achieving it would be fairly difficult. The depresolver is too entangled with other things in yum that it would be harder to pull out. If you're not pressed for time right away - wait a little bit longer and let me see if I can help make this more trivial to implement. Thanks -sv
