Yum 'replace' Plugin - Suggestions/Review

Hello all,

I am the core developer for the IUS Community Project [1] which provides 'replacement' packages for a handful of RHEL packages including php52, php53, mysql50, mysql51, etc.  The packages are intentionally re-named as to not automatically upgrade existing packages, and we do not 'Obsolete' stock RHEL packages either.  Our view is that replacing a RHEL package should be an explicit process and not something that just happens when you subscribe to a Yum repo.

That said, this packaging model introduces a slightly more complex upgrade process.  The current process is something similar to:

# yum shell

yum> remove php php-common php-pear php-mcrypt php-mysql php-mbstring

yum> install php52 php52-common php52-pear php52-mcrypt php52-mysql php52-mbstring

yum> transaction solve

yum> transaction run


The obvious headache is that the process (commands) are different on every box depending on what packages are installed and need to be removed/re-installed.  To this I have written a yum plugin that I think handles this process of upgrading from stock 'pkg' to a replacement 'pkgXY' quite well.  Not being an experienced yum coder (sorry skvidal/geppetto for all the questions in #yum) I was hoping to get any feedback or suggestions on this plugin, in the event that I'm doing anything obviously stupid.  The plugin is online at:

http://bazaar.launchpad.net/~derks/+junk/yum-plugin-replace/files


The usage is simple:

# yum replace php --replace-with php52



Thank you for your time and any feedback you may provide.

References:

[1] http://iuscommunity.org

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derks