TurnKey Linux's take on Ubuntu appliance development: KISS

[Scott Kitterman]

On Mon, 14 Dec 2009 15:23:28 +0100 Soren Hansen <soren at ubuntu.com> wrote:
>On Mon, Dec 07, 2009 at 11:12:04AM +0200, Alon Swartz wrote:
>>> Could you elaborate on this a little bit? Lots of different ideas
>>> have been tossed back and forth on various mailing lists, IRC and
>>> other fora, so I'm not completely sure what you mean Debian packages
>>> were not designed for.
>> What this means is that Debian packages were never designed for
>> system-level integration. They're meant to be building blocks for a
>> system administrator who then glues them together to integrate a
>> production solution.
>
>I disagree. There's nothing in the deb file format, nor the Debian
>Policy that prevents this. It simply defines a very strict set of rules
>for how it can be accomplished. I completely acknowledge, that there's a
>/tradition/ in Debian for treating packages as platform building blocks
>that the administrator is supposed to integrate with each other to form
>a complete solution of some sort. I would love nothing more than to see
>this change in Ubuntu. We've made some progress on the mail server
>front, but I see no reason not to extend this much further.
>
The bit of Debian policy that keeps getting quoted about packages not 
modifying conffiles of other packages is incomplete.  It goes on to say ... 
except through defined interfaces.  There is nothing in Debian Policy that 
prevents packages from being used for integration work.  It insists on 
properly engineered work.

As an example, Postfix provides postconf to externally manage main.cf.  We 
also have some Debian/Ubuntu scripts I did for Jaunty to give some ability 
to modify master.cf (which I plan to extend this cycle).

Since all policy requires is a defined interface, I feel those who say they 
are unduly constrained by policy are promoting the idea  that independent 
software components can be integrated without defined interfaces and the 
software engineer in me shudders.

Scott K