Packaging guidelines for web applications?

[John Dennis]

On Sun, 2006-05-07 at 22:42 +0200, Nicolas Mailhot wrote:

> The core of the problem is webapp authors choose monolithic filetree
> deployments for ease-of-development and ease-of-deployment reasons while
> the FHS mandates split trees for ease-of-administration reasons. And
> that all the infrastructure which makes pleasing admins not too hard for
> app authors is severily lacking for webapp authors.

Having packaged a number of webapps and previously researched a number
of these issues here are my working guidelines as of the moment (subject
to change on a whim :-)

* It's the job of the packager to split the webapp into separate
installation locations based on FHS and existing Fedora conventions.
This should be done via some type of parametrization, (e.g. adding
options to the autotool configure script). Those installation parameters
should default to match upstream but are overridden in the rpm spec
file. Those changes need to be submitted upstream, but because
everything defaults to match upstream there should be little resistance
to accepting the patch.

* The current convention of /var/www is probably broken, but the pain of
changing it is probably not worth it.

* Install the webapp "code" into /var/www/<package>
(or /usr/lib/<package>), config files into /etc/<package>, temporary
files created by the webapp belong in /var/cache/<package>

* Provide a /etc/httpd/conf.d/<package>.conf file which configures the
webapp for use with the Fedora conventions. (e.g. providing ScriptAlias,
modrewrite rules to map URL's to installation location, etc.)

* Absolutely nothing should install into the docroot.

* Not following existing Fedora conventions will play havoc with SELinux
which will cause much pain :-)

Note: I've studied FHS a number of times trying to make sure I follow
the guidelines and its clear to me that FHS is often ambiguous, or
rather that reasonable people could reasonably apply the FHS guidelines
differently but be compliant. Therefore don't get too hung up on FHS,
try to follow the spirit and when uncertain look for existing precedent
in Fedora.

-- 
John Dennis <jdennis at redhat.com>
Red Hat Inc.