How to make file paths configurable within an ArcGIS Python Add-In?

Question

This might be a general programming question but since I am doing it from within an Add-In therefore asking here at GIS forum. I have a project folder with sub-folders containing several files on my hard disk which I read from within my Python Add-In, its hard coded eg:

dem = r'C:/project/raster/dem'

and Add-In is in

r'C:/project/Add-In'

folder. I tried doing '../raster/dem' to define path of input raster layer but it failed to read. Please suggest how can I make it generic so that if I move project folder to D drive then Add-In would still be able to read data.

Answer 1

You could read in a configuration file stored under the user's profile. Because ArcGIS add-ins overwrite themselves every time the host application is opened, you don't want to store user-specific configuration information inside the add-in itself.

The configuration file can be in any format you want (eg XML, plain text), but the ConfigParser class makes reading and writing to an INI -like file format easy.

Answer 2

You can reference materials that are located within the add-in, everything that's included within the 'Install' directory will be copied into the appropriate location within AssemblyCache. You can then reference this by doing something like:

local_path = os.path.abspath(os.path.basename(__file__))
raster_path = os.path.join(local_path, 'rasters')

And from there, treat raster_path as a nomral path.