[GRASS-dev] Re: [GRASS GIS] #7: Location wizard: should predefine DB connection for new location

[Paul Kelly]

Sorry, just noticed there was a call to action by me in that bug report 
which I missed. Anyway, I think the key issue here is whether or not the 
database connection file is considered an essential part of a valid GRASS 
location.
1. If it *is*, then creation of it should be added to the places that 
crate locations: lib/init/mke_mapset.c and lib/gis/make_mapset.c.
2. If it is *not*, then the vector/db library functions that need to 
access it should be updated to either gracefully fail or create default 
settings on finding it absent, and this behaviour should be made 
consistent in all places.

Whatever way it is, I think adding a check to it in Init.sh is an ugly 
hack that just works around the problem rather than fixing it.

BUT: It seems option 1 is already partially implemented!
lib/init/mke_mapset.c (called if you create a new location using 
g.setproj, or the text-based startup) does indeed create the VAR file. So 
it looks to me that the anomaly is that this has been left out of 
lib/gis/make_mapset.c (called if you create a new location using g.proj, 
r.in.gdal or v.in.ogr or the GUI startup).

If we add creation of the VAR file to lib/gis/make_mapset.c, ideally we 
should also do an audit of the vector modules and remove the functionality 
that creates a default VAR file if not present, as it will no longer be 
needed. What do you think of this solution, Hamish?

Paul