/django/contrib/gis/gdal/driver.py
Python | 65 lines | 41 code | 10 blank | 14 comment | 8 complexity | 709b22b07477d227c4eae1776cd04b77 MD5 | raw file
Possible License(s): BSD-3-Clause
- # prerequisites imports
- from ctypes import c_void_p
- from django.contrib.gis.gdal.base import GDALBase
- from django.contrib.gis.gdal.error import OGRException
- from django.contrib.gis.gdal.prototypes import ds as capi
- # For more information, see the OGR C API source code:
- # http://www.gdal.org/ogr/ogr__api_8h.html
- #
- # The OGR_Dr_* routines are relevant here.
- class Driver(GDALBase):
- "Wraps an OGR Data Source Driver."
- # Case-insensitive aliases for OGR Drivers.
- _alias = {'esri' : 'ESRI Shapefile',
- 'shp' : 'ESRI Shapefile',
- 'shape' : 'ESRI Shapefile',
- 'tiger' : 'TIGER',
- 'tiger/line' : 'TIGER',
- }
-
- def __init__(self, dr_input):
- "Initializes an OGR driver on either a string or integer input."
- if isinstance(dr_input, basestring):
- # If a string name of the driver was passed in
- self._register()
- # Checking the alias dictionary (case-insensitive) to see if an alias
- # exists for the given driver.
- if dr_input.lower() in self._alias:
- name = self._alias[dr_input.lower()]
- else:
- name = dr_input
- # Attempting to get the OGR driver by the string name.
- dr = capi.get_driver_by_name(name)
- elif isinstance(dr_input, int):
- self._register()
- dr = capi.get_driver(dr_input)
- elif isinstance(dr_input, c_void_p):
- dr = dr_input
- else:
- raise OGRException('Unrecognized input type for OGR Driver: %s' % str(type(dr_input)))
- # Making sure we get a valid pointer to the OGR Driver
- if not dr:
- raise OGRException('Could not initialize OGR Driver on input: %s' % str(dr_input))
- self.ptr = dr
- def __str__(self):
- "Returns the string name of the OGR Driver."
- return capi.get_driver_name(self.ptr)
- def _register(self):
- "Attempts to register all the data source drivers."
- # Only register all if the driver count is 0 (or else all drivers
- # will be registered over and over again)
- if not self.driver_count: capi.register_all()
-
- # Driver properties
- @property
- def driver_count(self):
- "Returns the number of OGR data source drivers registered."
- return capi.get_driver_count()