Fiona from wheel does not set its GDAL_DATA path

[kannes]

Again/still struggling with the gdal and proj stuff (re #673 and #691).

From what I read, Fiona should set GDAL_PATH and PROJ_LIB to its own paths if there were no such paths defined in the environment yet.

I do not have GDAL_PATH or PROJ_LIB set, but Fiona still does not work :o)

I installed the latest version from pypi at https://pypi.org/project/Fiona/#files

pip install --user --upgrade https://files.pythonhosted.org/packages/b8/55/fdcd9a45b39a4fe50d79041d1194c2ebefcc7ef44958d54ad2b815129f02/Fiona-1.8.4-cp37-cp37m-manylinux1_x86_64.whl

import os

def checkpaths():
    gdal_data = os.environ.get('GDAL_DATA')
    if gdal_data:
      print(f"GDAL_DATA is set to {gdal_data}")
      if os.path.exists(gdal_data+"/gcs.csv"):
        print("GDAL_DATA seems correct")
      else:
        print("GDAL_DATA seems BROKEN")
    else:
      print(f"GDAL_DATA is NOT set")

    proj_lib = os.environ.get('PROJ_LIB')
    if proj_lib:
      print(f"PROJ_LIB is set to {proj_lib}")
      if os.path.exists(proj_lib+"/epsg"):
        print("PROJ_LIB seems correct")
      else:
        print("PROJ_LIB seems BROKEN")
    else:
      print(f"PROJ_LIB is NOT set")

>>> checkpaths()                                                                         
GDAL_DATA is NOT set
PROJ_LIB is NOT set

Importing Fiona now should have it update the paths to its own env, but it only sets the PROJ_LIB one.

>>> import fiona                                                                         

>>> checkpaths()                                                                         
GDAL_DATA is NOT set
PROJ_LIB is set to /home/kannes/.local/lib/python3.7/site-packages/fiona/proj_data
PROJ_LIB seems correct

This means that e.g. transformations will fail:

import fiona
from fiona.transform import transform_geom
from fiona.crs import from_epsg

eiffel_tower = {'type': 'Point', 'coordinates': (2.2945, 48.858222)}

crs_source_epsg = from_epsg(4326)
crs_target_epsg = from_epsg(25831)

transformed = transform_geom(crs_source_epsg, crs_target_epsg, eiffel_tower)
print(transformed)

prints:

ERROR 4: Unable to open EPSG support file gcs.csv.  Try setting the GDAL_DATA environment variable to point to the directory containing EPSG csv files.
ERROR 4: Unable to open EPSG support file gcs.csv.  Try setting the GDAL_DATA environment variable to point to the directory containing EPSG csv files.
ERROR 6: No translation for an empty SRS to PROJ.4 format is known.
{'type': 'Point', 'coordinates': (2.2945, 48.858222)}

If I manually set the correct GDAL_PATH before importing Fiona everything works fine:

# you MUST use a pristine Python session for this
import os

os.environ['GDAL_DATA'] = "/home/hannes/.local/lib/python3.7/site-packages/fiona/gdal_data"

import fiona
from fiona.transform import transform_geom
from fiona.crs import from_epsg

eiffel_tower = {'type': 'Point', 'coordinates': (2.2945, 48.858222)}

crs_source_epsg = from_epsg(4326)
crs_target_epsg = from_epsg(25831)

transformed = transform_geom(crs_source_epsg, crs_target_epsg, eiffel_tower)
print(transformed)

prints
{'type': 'Point', 'coordinates': (448251.81788407586, 5411935.123097671)}

[sgillies]

I got this straightened out in Rasterio, but haven't ported it here yet. Will do so for 1.8.5.

[kannes]

you rock

[felixink]

Could we use fiona._env.GDALDataFinder (private class) to mitigate this issue prior to the update (3/11/2018)?

import fiona
import os
os.environ['GDAL_DATA'] = fiona._env.GDALDataFinder.search_wheel(
    'literally any string')
...