ds = DataSource('/path/to/your/cities.shp') fails on first try (GDALException Unknown error code: "198770787"), but works on second

[Etiënne Thomassen]

I can not create a DataSource from a gpx file. It returns GDALException Unknown error code: "198770787" with the error code number seemingly random. However on the second try it works. And it does not even need to be the same file.

Python 3.6.0 (default, Dec 24 2016, 08:01:42) 
[GCC 4.2.1 Compatible Apple LLVM 8.0.0 (clang-800.0.42.1)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from django.contrib.gis.gdal import DataSource
>>> ds = DataSource('gpxfile1.gpx')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/etienne/.virtualenvs/venv1/lib/python3.6/site-packages/django/contrib/gis/gdal/datasource.py", line 64, in __init__
    Driver.ensure_registered()
  File "/Users/etienne/.virtualenvs/venv1/lib/python3.6/site-packages/django/contrib/gis/gdal/driver.py", line 83, in ensure_registered
    rcapi.register_all()
  File "/Users/etienne/.virtualenvs/venv1/lib/python3.6/site-packages/django/contrib/gis/gdal/prototypes/errcheck.py", line 119, in check_errcode
    check_err(result, cpl=cpl)
  File "/Users/etienne/.virtualenvs/venv1/lib/python3.6/site-packages/django/contrib/gis/gdal/error.py", line 74, in check_err
    raise GDALException('Unknown error code: "%s"' % code)
django.contrib.gis.gdal.error.GDALException: Unknown error code: "-1935278031"
>>> ds = DataSource('gpxfile2.gpx')
>>> ds.layer_count
5

This post on StackOverflow pointed me in this direction: ​http://stackoverflow.com/questions/41775536/datasource-gdalexception-unknown-error-code-474873798

Strangely, I can now get it to work doing this in my app:

try:
    datasource = DataSource(target_path)
except:
    datasource = DataSource(target_path)

Btw this part of my app stopped working migrating from Django 1.8 and Python 2.7 to Django 1.9 and Python 3.6. Now on Django 1.10 and Python 3.6