[FEATURE] Configure custom environment variables

[dakcarto]

• Fix for [BUGFIX][Processing][Rscript] Use Extent Parameter #3097
• Could help plugins, like SEXTANTE, work better across platforms via abstracted coding based upon env vars
• In app prefs, configure variables and view current set, with tooltips to show pre-startup value (if any)

[dakcarto]

Hi,

Would appreciate a test of this on Windows platform. To test, set some custom vars in the dialog, restart QGIS and see if the vars are in the 'current' vars table; then, verify they are passed down to Python by running the following in console:

import os
os.environ

Dialog should look like this:
http://drive.dakotacarto.com/qgis/app-prefs_custom-env-vars.png

Feature branch is available here:
https://github.com/dakcarto/Quantum-GIS/tree/iface_enviro_3

[timlinux]

Hi

It would be nice to filter the env vars to show only the QGIS specific ones e.g. QGIS_PREFIX_PATH etc.

Regards

Tim

[dakcarto]

Do you mean a general line edit filter for the 'current' env vars table? Or a 'Show QGIS variables' checkbox? Maybe just style the base set of known QGIS-specific vars to italics?

With ever new SEXTANTE algorithms looking for env var configuration from external installs, it might be problematic to keep up with what is considered QGIS-specific.

[dakcarto]

I would like to merge this if no one has any other concerns, suggestions or comments.

On Mac, this is just the first step towards getting SEXTANTE to fully work with its external processes. Also, it would be good to go through the codebase and remove the hardcoded env vars currently being set for Mac (mostly for GDAL and GRASS) and move them into this custom env var setup. So, there is still a bit of work and a lot of testing to do for SEXTANTE on Mac before the 2.0 release.

[timlinux]

Hi

With ever new SEXTANTE algorithms looking for env var configuration from external installs, it might be problematic to keep up with what is considered QGIS-specific.

Indeed. Perhaps the rule of thumb would be 'those defined / used in the C++ API and those with QGIS in the env var name"

+1 from me to merge anyway.

Regards

Tim