[AG-DEV] Re: Location of AG config files

[Tobias Schiebeck]

Hi,

Beeing a Debian user for some years now, I know that Debian has
sometimes strange ideas how to package things. On the other hand I was
slightly surprised to find "code" such as the SharedPresentation
implementation under /etc . IMHO /etc is the place for config files and
thats what I think Debian is trying to enforce (which I don't think is
the right thing to do but ...) 

On Thu, 2008-09-11 at 07:55 -0500, Thomas D. Uram wrote: 
> Chris:
> 
> What's the chance that a future change will also impact files under 
> /usr/share, requiring another adjustment?  Is there any guidance from 
> the debian/ubuntu community about how to adjust, or where such files 
> should be placed?
> > (One way around this would be to create a single mega-package of AG & 
> > related service packages, but I feel it would be an unsatisfying, if 
> > not "wrong", solution) 
> I agree that this is not the right way to go.

I think /usr/share is where the NodeServices and other "code" should be
placed and should be fairly safe from changes. The pure configuration
files such as the nodeConfig could stay under /etc as it would be
recreated if it isn't there, and /etc is the place where people look for
these general configuration stuff.

Best Wishes

Tobias
> 
> Tom
> 
> 
> 
> On 9/8/08 6:37 PM, Christoph Willing wrote:
> > Tom,
> >
> > There is a problem with the Debian & Ubuntu AG packages. The revamped 
> > build tool mechanisms introduced early this year to accommodate 
> > multiple python versions on the same machine has an unfortunate side 
> > effect; anything under /etc is considered to be owned by a particular 
> > package and is removed completely during upgrades or reinstallations, 
> > regardless of whether another package may be using the same area.
> >
> > In the case of the AG installation, a number of configuration files 
> > are kept in directories under /etc/AccessGrid3. In particular, 
> > /etc/AccessGrid3/NodeServices normally contains the standard Audio & 
> > Video Services. However other packages may want to install services 
> > there too e.g. vpcscreen, aghdvic. Initial installation of these 
> > packages works OK but if the AG package is reinstalled or upgraded, 
> > the additional services are also removed.
> >
> > (One way around this would be to create a single mega-package of AG & 
> > related service packages, but I feel it would be an unsatisfying, if 
> > not "wrong", solution)
> >
> > This (new) unwanted behaviour occurs because of the special treatment 
> > given to files/directories under /etc, so an solution is to use a 
> > different location. I have done some testing using 
> > /usr/share/AccessGrid3 instead of /etc/AccessGrid3 as a location for 
> > the config files. With this new location, any number of installations, 
> > reinstallations etc. of the AG  & related packages can now be 
> > performed without any interference to each other. Introducing the new 
> > location is trivial - a single line patch to the toolkit code itself, 
> > as well as a single line change in the packaging script of each 
> > affected package (accessgrid3.x, vpcscreen, aghdvic, etc.)
> >
> >
> > Since this is a Debian & Ubuntu specific problem, I don't expect that 
> > relocating /etc/AccessGrid3 needs to apply to all distributions 
> > (although it may be worth considering). However before I release any 
> > packages with the new file layout, do you have strong feelings about 
> > the proposed solution - or alternative solutions?
> >
> > I've cc'd to AG-DEV in case someone more conversant with Debian/Ubuntu 
> > Policies & packaging practices can offer advice; please chime in - I'm 
> > just a part-timer in this area and I'm keen to receive suggestions.
> >
> >
> >
> > chris
> >
> >
> > Christoph Willing                        +617 3365 8350
> > QCIF Access Grid Manager
> > University of Queensland
> >
> >
> >
> >
> >
> 
-- 
---------------------------------------------------------------------
Tobias Schiebeck                    tobias.schiebeck at manchester.ac.uk
Research Computing Services           http://www.rcs.manchester.ac.uk
The University of Manchester                  tel: (+44) 161-275-0601
---------------------------------------------------------------------