Handle Flup dependency in module sitescripts

[matze]

When we need multiplexer.fcgi from sitescripts in production, we currently configure it's dependencies (namely package python-flup) manually every time - which not only violates the DRY principle but also implies the requirement for implementation-specific knowledge where it should not be necessary:

$ grep -R python-flup *
modules/updateserver/manifests/init.pp:  package {'python-flup':}
modules/updateserver/manifests/init.pp:      Package["python-flup"],
modules/web/manifests/server.pp:    package {'python-flup':}
modules/web/manifests/server.pp:        Package["python-flup"],

Instead we should either a) introduce a $fcgi_support parameter in modules/sitescripts/manifests/init.pp that triggers the installation of the package, or b) always install that package with module sitescripts.

[fhd]

Good idea!

I'm voting for b - I don't see any problem with the sitescripts module installing all of the sitescripts dependencies, whether the parts requiring those are used or not. It's not like we have a lot of dependencies.

Bit of a separate topic, but seeing how we always seem to start the multiplexer with spawn-fcgi - we _might_ want to consider moving that to a define in sitescripts to further simplify things.

[matze]

Agreed. I've thought about spawn-fcgi when writing this ticket, but I am not sure whether sitescripts is the best place for that - it's not a dependency, in contrast to python-flup. However, as you wrote already, it's a separate topic. I will take care of a follow-up for that one.

[matze]

(Let's adress this after #2277 is pushed, in order to avoid confusion and to allow for a single, clean patch-set per issue.)

[abpbot]

A commit referencing this issue has landed:
​Issue 2313 - Handle Flup dependency in module sitescripts