rgrass7 and OsGeo4W on Windows - environment variables for R

rgrass7-setup-win-osgeo4w.R

# Source this file at the top of an R or Rmd file using rgrass7 together
# with GRASS installed via OSGeo4W (https://trac.osgeo.org/osgeo4w/) on a
# Windows machine.

# e.g. source(file.path(getwd(), 'rgrass7-setup-win-osgeo4w.R'))

# You can alternatively add the contents to a project-specific .Rprofile.

# Its better to set these variables in an R session rather than in System,
# especially if you have other GIS software like PostGIS installed, which has
# its own GDAL_DATA path. This is also the only solution for Windows users on
# accounts lacking admin rights.

# Note that if you call `library(sf)` after setting these variables, GDAL_DATA
# will be overwritten!

# These paths are current to 2022-01-25 and may change in future. If you get
# stuck, open a question on gis.stackexchange or r-sig-geo. I'm not resourced
# to respond to one-on-one contacts on this topic.

# from /bin/o4w_env.bat:
Sys.setenv('OSGEO4W_ROOT' = file.path('C:', 'OSGeo4W'))
# NB Change the above if you installed OSGeo4W in a non-standard location.

# from %OSGEO4W_ROOT%/etc/ini/gdal.bat
Sys.setenv('GDAL_DATA' =
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'share', 'gdal'))
Sys.setenv('GDAL_DRIVER_PATH' =
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'bin', 'gdalplugins'))

# from %OSGEO4W_ROOT%/etc/ini/libjpeg.bat (optional?)
Sys.setenv('JPEGMEM' = 1000000)

# from %OSGEO4W_ROOT%/etc/ini/openssl.bat (optional?)
Sys.setenv('OPENSSL_ENGINES' =
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'lib', 'engines-1_1'))

# from %OSGEO4W_ROOT%/etc/ini/proj.bat
Sys.setenv('PROJ_LIB' =
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'share', 'proj'))

# from %OSGEO4W_ROOT%/etc/ini/python3.bat
Sys.setenv('PYTHONHOME' =
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Python39'))
Sys.setenv('PYTHONUTF8' = 1)

# from %OSGEO4W_ROOT%/etc/ini/qt5.bat (optional?)
Sys.setenv('QT_PLUGIN_PATH' = 
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Qt5', 'plugins'))
Sys.setenv('O4W_QT_PREFIX' = 
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Qt5'))
Sys.setenv('O4W_QT_BINARIES' = 
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Qt5', 'bin'))
Sys.setenv('O4W_QT_PLUGINS' = 
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Qt5', 'plugins'))
Sys.setenv('O4W_QT_LIBRARIES' = 
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Qt5', 'lib'))
Sys.setenv('O4W_QT_TRANSLATIONS' = 
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Qt5', 'translations'))
Sys.setenv('O4W_QT_HEADERS' = 
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Qt5', 'include'))
Sys.setenv('O4W_QT_DOC' = 
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'Qt5', 'doc'))

# from%OSGEO4W_ROOT%/apps/grass/grass78/etc/env.bat
Sys.setenv('GISBASE' =
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'apps', 'grass', 'grass78'))
Sys.setenv('GRASS_PYTHON' =
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'bin', 'python3.exe'))
Sys.setenv('PYTHONPATH' =
             file.path(Sys.getenv('GISBASE'), 'etc', 'python'))
Sys.setenv('GRASS_PROJSHARE' =
             file.path(Sys.getenv('OSGEO4W_ROOT'), 'share', 'proj'))
Sys.setenv('FONTCONFIG_FILE'=
             file.path(Sys.getenv("GISBASE"), 'etc', 'fonts.conf'))

# NB the appropriate path for the next two variables may vary depending on your
# Windows version and your account permissions. If in doubt, open GRASS-GUI,
# define a database, open a new location, exit, and then search your user
# directory for a folder called 'GRASS7'. Edit the paths below to match. This
# should only be necessary once after a clean installation of GRASS, or if you
# refresh your user profile.

# If GISRC is defined but no rc file exists at the specified location,
# `library('rgrass7')` will fail with an error about XML. Either skip setting
# this variable, or manually initialise GRASS as described above before
# proceeding.

if(!file.exists(file.path(Sys.getenv('USERPROFILE'), 'AppData', 'Roaming',
                          'GRASS7', 'rc'))) {
     message('Missing rc file in expected location.')
   } else {
     Sys.setenv('GISRC' =
                  file.path(Sys.getenv('USERPROFILE'), 'AppData', 'Roaming',
                            'GRASS7', 'rc'))
   }
Sys.setenv('GRASS_ADDON_BASE' =
             file.path(Sys.getenv('USERPROFILE'), 'AppData', 'Roaming',
                       'GRASS7', 'addons'))
# lastly,
Sys.setenv('PATH' =
             paste(file.path(Sys.getenv('GISBASE'), 'lib'),
                   file.path(Sys.getenv('GISBASE'), 'bin'),
                   Sys.getenv('GRASS_ADDON_BASE'),
                   Sys.getenv('O4W_QT_BINARIES'),			 
                   file.path(Sys.getenv('PYTHONHOME'), 'Scripts'), # python3.bat
                   file.path(Sys.getenv('OSGEO4W_ROOT'), 'bin'),   #o4w_env.bat                   ,
                   Sys.getenv("PATH"),
                   sep = .Platform$path.sep))

# Be aware that if you have other Python or GRASS installs on your PATH already,
# you might need to alter the relative position of `Sys.getenv("PATH")` above.

I am working with newer rgrass and I want to interface with GRASS GIS version 8.2. What modifications would I make to get this to work for me? When I run
initGRASS(gisBase = "C:/Program Files/GRASS GIS 8.2", home = tempdir())
I get a warning with the message:

In system(syscmd, intern = intern, ignore.stderr = ignore.stderr,  :
  running command 'g.proj.exe -w' had status 1

Hi @fgashakamba, should all pretty much work the same. The error you're seeing is related to a different unsolved bug, see rsbivand/rgrass#33 and OSGeo/grass#1955. No solve yet unfortunately, but it won't prevent most execGRASS() calls from running.

Thanks for the response. Unfortunately, the issue DOES prevent me from running my execGRASS() calls. Well, they run but they give empty result. I posted the issue at the rgrass gitHub page and @rsbivand (Roger Bivand) helped me diagnose that the root cause of the problem is the fact that WinGRASS loads a slightly old proj.db version that isn't compatible with the version loaded by terra. There is no solution suggested but I think I will continue playing with combinations of old versions of rgrass, WinGRASS, and terra and see if I can find a combo that plays nicely together.

Ah interesting - I haven't had any problems myself lately (running a relative elevation model workflow, YMMV), but from the install path you posted above it looks like you're using a standalone installation of GRASS rather than the OSGeo4W version. GRASS 8.2 is available through the OSGeo4W package manager - use the advanced option in the installer to choose it.

Yes @obrl-soil, it seems like the OSGeo4W version of GRASS is updated more constantly than the Windows standalone installer. Here are more details on that. I will try that one and see if it solves my problem.