Support for PostGIS backend optionally

[diranged]

Optionally support django.contrib.gis.db.backends.postgis as the DB backend

[KristianOellegaard]

Wouldn't it be better to implement a setting where you specify your BaseDatabaseWrapper, DjangoCursorWrapper and BaseDatabaseCreation of choice? Then this would work with django-hstore and more, as well.

[kennethreitz]

+1, Mozilla's MySQL pool works this way. I would love to implement that.

[diranged]

So I wanted to do that originally, but I found if I tried to import any DatabaseWrappers inside the Django settings file, I run into this error:

from django.contrib.gis.db.backends.postgis.base import DatabaseWrapper
Traceback (most recent call last):
File "", line 1, in
File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/contrib/gis/db/backends/postgis/base.py", line 1, in
from django.db.backends.postgresql_psycopg2.base import *
File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/db/init.py", line 11, in
if DEFAULT_DB_ALIAS not in settings.DATABASES:
File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/utils/functional.py", line 184, in inner
self._setup()
File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/conf/init.py", line 40, in _setup
raise ImportError("Settings cannot be imported, because environment variable %s is undefined." % ENVIRONMENT_VARIABLE)
ImportError: Settings cannot be imported, because environment variable DJANGO_SETTINGS_MODULE is undefined.

[KristianOellegaard]

You could just write a string in the settings file and then do the import in the module, based in the settings value ;)

e.g.

DATABASE_POOL_CONFIG = {
    'BaseDatabaseWrapper': 'some.path.to.BaseDatabaseWrapper',
    'DjangoCursorWrapper': 'some.path.to.DjangoCursorWrapper',
    'BaseDatabaseCreation': 'some.path.to.BaseDatabaseCreation'
}

[diranged]

I tried something like this:

DEFAULT_POOL_CONFIG = {
    'BaseDatabaseWrapper': 'django.contrib.gis.db.backends.postgis.base.DatabaseWrapper',
    'DjangoCursorWrapper': 'django.contrib.gis.db.backends.postgis.base.CursorWrapper',
    'BaseDatabaseCreation': 'django.contrib.gis.db.backends.postgis.creation.DatabaseCreation',
}

def _import_class(cl):
    d = cl.rfind(".")
    classname = cl[d + 1:len(cl)]
    m = __import__(cl[0:d], globals(), locals(), [classname])
    return getattr(m, classname)


# Look up the DATABASE_POOL_CONFIG settings. If they are supplied, use the to
# dynamically import the objects we're going to wrap. If they are not set, use
# the defaults configured at the top of this package.
pool_config = getattr(settings, 'DATABASE_POOL_CONFIG', DEFAULT_POOL_CONFIG)
BaseDatabaseWrapper = _import_class(pool_config['BaseDatabaseWrapper'])
DjangoCursorWrapper = _import_class(pool_config['DjangoCursorWrapper'])
BaseDatabaseCreation = _import_class(pool_config['BaseDatabaseCreation'])

but I end up with errors because you refer to many components of django.contrib.gis.db.backends.postgis.base by importing *..

(nextdoor-ve)diranged@mwise-x64-dev:~/src/nextdoor.com/apps/nextdoor$ python manage.py shell
Traceback (most recent call last):
  File "manage.py", line 6, in <module>
    execute_manager(settings)
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/core/management/__init__.py", line 459, in execute_manager
    utility.execute()
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/core/management/__init__.py", line 382, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/core/management/__init__.py", line 261, in fetch_command
    klass = load_command_class(app_name, subcommand)
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/core/management/__init__.py", line 69, in load_command_class
    module = import_module('%s.management.commands.%s' % (app_name, name))
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/utils/importlib.py", line 35, in import_module
__import__(name)
  File "/home/diranged/src/nextdoor.com/apps/nextdoor/../nextdoor/web/management/commands/shell.py", line 2, in <module>
    from nextdoor.web import signals
  File "/home/diranged/src/nextdoor.com/apps/nextdoor/../nextdoor/web/signals.py", line 14, in <module>
    from django.contrib.auth.models import User
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/contrib/auth/models.py", line 5, in <module>
    from django.db import models
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/db/__init__.py", line 40, in <module>
    backend = load_backend(connection.settings_dict['ENGINE'])
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/db/__init__.py", line 34, in __getattr__
    return getattr(connections[DEFAULT_DB_ALIAS], item)
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/db/utils.py", line 92, in __getitem__
    backend = load_backend(db['ENGINE'])
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/db/utils.py", line 24, in load_backend
    return import_module('.base', backend_name)
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/home/diranged/src/nextdoor.com/apps/nextdoor/../nextdoor/db/backend/base.py", line 21, in <module>
    from django_postgrespool import base as database_base
  File "/opt/nextdoor-ve/lib/python2.7/site-packages/django_postgrespool/base.py", line 46, in <module>
   db_pool = manage(Database, **pool_args)
NameError: name 'Database' is not defined

[MRigal]

I have actually a big + one for this !

[gonzalodiaz]

Was the support for django.contrib.gis.db.backends.postgis added elsewhere?

[cmcavoy]

also interested in where this landed....is there a way to use postgis with this library?

[Starefossen]

+1 for being able to use PostGIS with Django-PostgresPool

[leibowitz]

Still no support/planned support for postgis in postgrespool?