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Debian build-depends metapackages

When I’m doing development on an existing software project, and especially when I’m trying to bugfix something with a Debian package, I find that I install random packages I need to rebuild something, and then later on I’m wondering why I’ve got those installed. I tend to try to keep with the philosophy that the bits of software I’m using are pretty knowledgeable about whatever they’re intended to do, and so trusting them to make smart decisions is a good idea. For package managers, this means I should only keep track of the software that I actually use, and tell the package manager that everything else has been automatically installed and can therefore be removed when they cease to be a dependency of something I actually need. Having packages that I only installed for building something else without a record of that in the package management system breaks that mental model.

Enter dh-builddep-metapackage (the naming is inline with the names used by the debhelper scripts used for other debian packaging stuff). dh-builddep-metapackage builds build-dependency metapackages in order to ease package
management for package rebuilders. In effect, it builds a “<package name>-builddep” package that has no content, but depends on everything that the existing package build-depends on. By using dh-builddep-metapackage to create metapackages rather than using “apt-get build-dep”, I keep a record in the package management about why I need a particular development package, and can remove the dependant packages when I’m no longer working with the relevant source package.

I think someone’s done this before, but some work with Google didn’t find it, and it was an interesting exercise anyway. Standard usage is “dh-builddep-metapackage -b <package name>”, which will create the metapackage data and build the package for you using dpkg-buildpackage. A folder called “<package name>-<package version>” will be created in the current local directory, and if an existing folder exists then dh-builddep-metapackage will refuse to overwrite it (unless you give the -o/–overwrite option).

So far I’ve used it a few times, and it’s quite nice to have those packages around to remind me about the dependencies. I’m considering building a full repository with *-builddep packages for everything in the Debian archives, but I’d like to make sure I’d use this enough first.

by
Tom Parker
on
12/04/10
 
 


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