Create a -cli package without a different executable

[Nicoleau Fabien]

Le Sat, 19 Dec 2009 22:08:45 -0800,
Toshio Kuratomi <a.badger at gmail.com> a écrit :

> On Fri, Dec 18, 2009 at 10:39:18PM +0100, Julian Aloofi wrote:
> > Am Freitag, den 18.12.2009, 18:12 +0100 schrieb Nicoleau Fabien:
> > > Hi,
> > > 
> > > I'm packaging phatch that provides /usr/bin/phatch, a graphical
> > > application to manage some operations on photos. It handles
> > > command line parameters so that it can be used in a script,
> > > without a GUI : if no parameters are given, a GUI is displayed,
> > > otherwise it acts as a console application.
> > > 
> > > Upstream asked me if it's possible to keep "phatch" package,
> > > containing the graphical requirements (and requires) and requires
> > > phatch-cli, and create a phatch-cli, that
> > > provides /usr/bin/phatch. With this way, people could just
> > > install phatch-cli on a server and use it with command line
> > > parameters (but it would crash if it's not launched with
> > > parameters).
> > > 
> > > My question is :
> > > is it good to provide a -cli package that does not provides a
> > > separate script or executable file, and that will work only if
> > > the user is carefull to not launch it in a way that it does not
> > > require a graphic lib (without parameters in that context) ?
> > > 
> Sounds like the goal is good but the implementation is not.
> 
> > > 
> > I see phatch is a python package, so I think a little trick could be
> > possible:
> > 
> > %package cli:
> > BuildRequires:	python-devel
> > Requires:	non-gui-dependencies
> > %files
> > {_bindir}/phatch
> > 
> > and for the main package:
> > Requires:	phatch-cli
> > Requires:	pygtk2, <gui-dependencies>
> > [install desktop file etc...]
> > 
> > 
> > This way users could explicitly install phatch-cli, and it would
> > "only" not start up properly if called without arguments on a
> > terminal, and the main package (gui version) would contain the
> > program and pull in the graphical dependencies.
> > I don't know the program though, and if the cli version depends on
> > gui libraries to work properly as well it wouldn't work.
> 
> This is not ideal but it needs some coding to come up with something
> better. Possibilities:
> 
> * phatch with no options can attempt to import a gui lib.  If that
>   succeeds it launches the graphical interface.  If it does not
> succeed, it displays the usage/help message.
> * phatch is a command line app.  When invoked as gphatch it starts as
>   a gui app instead.  The phatch-gui subpackage installs a symlink
> from /usr/bin/gpatch to /usr/bin/phatch as well as .desktop files.
> 
> Basically, it's great to have the option to get the functionality of
> the program without having to install the GUI environment.  But the
> program tracebacking when the GUI environment is not present and the
> user typed the command name without options is not good behaviour for
> a program.
> 
> -Toshio

In fact I was wrong about the fact that phatch will crash if it's
called with no params (so as the gui version). A message is displayed
and tells and explain that the user has to install 'phatch' (containing
gui stuff). 

So its seems pretty clean to me, and easy to manage.

Fabien Nicoleau