app/django/contrib/gis/gdal/driver.py
changeset 323 ff1a9aa48cfd
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/contrib/gis/gdal/driver.py	Tue Oct 14 16:00:59 2008 +0000
@@ -0,0 +1,66 @@
+# prerequisites imports 
+from ctypes import c_void_p
+from django.contrib.gis.gdal.error import OGRException
+from django.contrib.gis.gdal.prototypes.ds import \
+    get_driver, get_driver_by_name, get_driver_count, get_driver_name, register_all
+
+# 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(object):
+    "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._ptr = None # Initially NULL
+            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 = get_driver_by_name(name)
+        elif isinstance(dr_input, int):
+            self._register()
+            dr = 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 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: register_all()
+                    
+    # Driver properties
+    @property
+    def driver_count(self):
+        "Returns the number of OGR data source drivers registered."
+        return get_driver_count()