[Qgis-developer] Module dependencies

[Paolo Cavallini]

Il 23/09/2014 12:58, Vincent Picavet ha scritto:

> Actually the general plugin dependencies problem is a distribution problem, 
> and should not be solved inside QGIS. We really do not want to reimplement a 
> multi-platform package management software.

sure thing, but currently installing an additional libs on win is pretty difficult,
and we would better do what is possible, reusing what is already available, to make
user life easier.

> As stated before, auto-installing packages should also be done with great 
> care, which is as well why package management software exist in the first 
> place.

agreed, see above. however, please not that currently many win users would install
whatever, even from unknown sources, to solve their problems. if we can improve this,
much better

> There are a few possibilities to improve the current situation :
> * Make it clear for the user that additional packages are needed for a plugin, 
> and show him a page explaining how to install them, according to its platform.

+1

> * Have a stricter policy on plugins regarding external dependencies (e.g. do 
> not accept plugins in official repo which have dependencies on packages not 
> included in osgeo4w, or default qgis binaries)

-1, as it would block a number of interesting developments

> * Have these dependency informations available in the plugin's metadata

+1

> * Have a better plugin architecture, which makes it easier to deal with 
> dependencies, using tools made for that purpose (i.e. make qgis plugins real 
> python packages installable with pip install).

even better

> I think the main point is first to warn the user and guide him for further 
> install steps, instead of getting python "import failed" errors.

agreed

thanks for your thoughts
-- 
Paolo Cavallini - www.faunalia.eu
Corsi QGIS e PostGIS: http://www.faunalia.eu/training.html