def add_aois_to_shapefile(self, ds, job_object):
aois = job_object.aois.all()
if len(aois) == 0:
return
geo_field = aois[0].polygon
# Get the right geometry type number for ogr
ogr_type = OGRGeomType(geo_field.geom_type).num
# Set up the native spatial reference of the geometry field using the srid
native_srs = SpatialReference(geo_field.srid)
# create the AOI layer
layer = lgdal.OGR_DS_CreateLayer(ds, 'lyr', native_srs._ptr, ogr_type,
None)
# Create the fields that each feature will have
fields = AOI._meta.fields
attributes = []
for field in fields:
if field.name in 'id, active, name, created_at, updated_at, analyst, priority, status, properties':
attributes.append(field)
for field in attributes:
data_type = 4
if field.name == 'id':
data_type = 0
fld = lgdal.OGR_Fld_Create(str(field.name), data_type)
added = lgdal.OGR_L_CreateField(layer, fld, 0)
check_err(added)
# Getting the Layer feature definition.
feature_def = lgdal.OGR_L_GetLayerDefn(layer)
# Loop through queryset creating features
for item in aois:
feat = lgdal.OGR_F_Create(feature_def)
for idx, field in enumerate(attributes):
if field.name == 'properties':
value = json.dumps(item.properties)
else:
value = getattr(item, field.name)
string_value = str(value)[:80]
lgdal.OGR_F_SetFieldString(feat, idx, string_value)
# Transforming & setting the geometry
geom = item.polygon
ogr_geom = OGRGeometry(geom.wkt, native_srs)
check_err(lgdal.OGR_F_SetGeometry(feat, ogr_geom._ptr))
# create the feature in the layer.
check_err(lgdal.OGR_L_CreateFeature(layer, feat))
check_err(lgdal.OGR_L_SyncToDisk(layer))
def add_features_subset_to_shapefile(self, ds, features, layer_name):
if len(features) == 0:
return
geo_field = features[0].the_geom
# Get the right geometry type number for ogr
ogr_type = OGRGeomType(geo_field.geom_type).num
# Set up the native spatial reference of the geometry field using the srid
native_srs = SpatialReference(geo_field.srid)
# create the Feature layer
layer = lgdal.OGR_DS_CreateLayer(ds, layer_name, native_srs._ptr,
ogr_type, None)
# Create the fields that each feature will have
fields = Feature._meta.fields
attributes = []
for field in fields:
if field.name in 'id, analyst, template, created_at, updated_at, job, project':
attributes.append(field)
for field in attributes:
data_type = 4
if field.name == 'id':
data_type = 0
fld = lgdal.OGR_Fld_Create(str(field.name), data_type)
added = lgdal.OGR_L_CreateField(layer, fld, 0)
check_err(added)
# Getting the Layer feature definition.
feature_def = lgdal.OGR_L_GetLayerDefn(layer)
# Loop through queryset creating features
for item in features:
feat = lgdal.OGR_F_Create(feature_def)
for idx, field in enumerate(attributes):
value = getattr(item, field.name)
# if field.name == 'template':
# value = value.name
string_value = str(value)
lgdal.OGR_F_SetFieldString(feat, idx, string_value)
# Transforming & setting the geometry
geom = item.the_geom
ogr_geom = OGRGeometry(geom.wkt, native_srs)
check_err(lgdal.OGR_F_SetGeometry(feat, ogr_geom._ptr))
# create the feature in the layer.
check_err(lgdal.OGR_L_CreateFeature(layer, feat))
check_err(lgdal.OGR_L_SyncToDisk(layer))
class ShpResponder(object):
def __init__(self, queryset, readme=None, geo_field=None, proj_transform=None, mimetype='application/zip',file_name='shp_download'):
"""
"""
self.queryset = queryset
self.readme = readme
self.geo_field = geo_field
self.proj_transform = proj_transform
self.mimetype = mimetype
self.file_name = file_name
def __call__(self):
"""
"""
fields = self.queryset.model._meta.fields
geo_fields = [f for f in fields if isinstance(f, GeometryField)]
geo_fields_names = ', '.join([f.name for f in geo_fields])
attributes = [f for f in fields if not isinstance(f, GeometryField)]
if len(geo_fields) > 1:
if not self.geo_field:
raise ValueError("More than one geodjango geometry field found, please specify which to use by name. Available fields are: '%s'" % geo_fields_names)
else:
geo_field_by_name = [fld for fld in geo_fields if fld.name == self.geo_field]
if not geo_field_by_name:
raise ValueError("Geodjango geometry field not found with the name '%s', fields available are: '%s'" % (self.geo_field,geo_fields_names))
else:
geo_field = geo_field_by_name[0]
elif geo_fields:
geo_field = geo_fields[0]
else:
raise ValueError('No geodjango geometry fields found in this model queryset')
ogr.OGRRegisterAll()
# Get the shapefile driver
dr = ogr.OGRGetDriverByName('ESRI Shapefile')
# create a temporary file to write the shapefile to
# since we are ultimately going to zip it up
tmp = tempfile.NamedTemporaryFile(suffix='.shp', mode = 'w+b')
# we must close the file for GDAL to be able to open and write to it
tmp.close()
# Creating the datasource
ds = ogr.OGR_Dr_CreateDataSource(dr,tmp.name, None)
# Get the right geometry type number for ogr
ogr_type = OGRGeomType(geo_field._geom).num
# Set up the spatial reference with epsg code
srs = SpatialReference(geo_field._srid)
# If true we're going to reproject later on
if self.proj_transform:
srs = SpatialReference(self.proj_transform)
# Creating the layer
layer = ogr.OGR_DS_CreateLayer(ds,os.path.basename(tmp.name), srs._ptr, ogr_type, None)
# Create the fields
# Todo: control field order as param
for field in attributes:
fld = ogr.OGR_Fld_Create(str(field.name), 4)
added = ogr.OGR_L_CreateField(layer, fld, 0)
check_err(added)
# Getting the Layer feature definition.
feature_def = ogr.OGR_L_GetLayerDefn(layer)
# Loop through queryset creating features
for item in self.queryset:
feat = ogr.OGR_F_Create(feature_def)
# For now, set all fields as strings
# TODO: catch model types and convert to ogr fields
# http://www.gdal.org/ogr/classOGRFeature.html
# OGR_F_SetFieldDouble
#OFTReal => FloatField DecimalField
# OGR_F_SetFieldInteger
#OFTInteger => IntegerField
#OGR_F_SetFieldStrin
#OFTString => CharField
# OGR_F_SetFieldDateTime()
#OFTDateTime => DateTimeField
#OFTDate => TimeField
#OFTDate => DateField
idx = 0
for field in attributes:
value = getattr(item,field.name)
try:
string_value = str(value)
except UnicodeEncodeError, E:
# pass for now....
# http://trac.osgeo.org/gdal/ticket/882
string_value = ''
ogr.OGR_F_SetFieldString(feat, idx, string_value)
idx += 1
# Transforming & setting the geometry
geom = getattr(item,geo_field.name)
#import pdb;pdb.set_trace()
# if requested we transform the input geometry
# to match the shapefiles projection 'to-be'
if geom:
if self.proj_transform:
geom.transform(self.proj_transform)
ogr_geom = OGRGeometry(geom.wkt,srs)
# create the geometry
check_err(ogr.OGR_F_SetGeometry(feat, ogr_geom._ptr))
else:
# Case where geometry object is not found because of null value for field
# effectively looses whole record in shapefile if geometry does not exist
pass
# creat the feature in the layer.
check_err(ogr.OGR_L_SetFeature(layer, feat))
# Cleaning up
check_err(ogr.OGR_L_SyncToDisk(layer))
ogr.OGR_DS_Destroy(ds)
ogr.OGRCleanupAll()
#Read resulting shapefile into a zipfile buffer
buffer = cStringIO.StringIO()
zip = zipfile.ZipFile(buffer, 'w', zipfile.ZIP_DEFLATED)
files = ['shp','shx','prj','dbf']
for item in files:
filename= '%s.%s' % (tmp.name.strip('.shp'), item)
zip.write(filename, arcname='%s.%s' % (self.file_name.rstrip('.shp'), item))
if self.readme:
zip.writestr('README.txt',self.readme)
zip.close()
buffer.flush()
zip_stream = buffer.getvalue()
buffer.close()
# Stick it all in a django HttpResponse
response = HttpResponse()
response['Content-Disposition'] = 'filename=%s.zip' % self.file_name.rstrip('.shp')
response['Content-length'] = str(len(zip_stream))
response['Content-Type'] = self.mimetype
response.write(zip_stream)
return response
# pass for now....
# http://trac.osgeo.org/gdal/ticket/882
string_value = ''
lgdal.OGR_F_SetFieldString(feat, idx, string_value)
# Transforming & setting the geometry
geom = getattr(item, geo_field.name)
# if requested we transform the input geometry
# to match the shapefiles projection 'to-be'
if geom:
ogr_geom = OGRGeometry(geom.wkt, output_srs)
if self.proj_transform:
ct = CoordTransform(native_srs, output_srs)
ogr_geom.transform(ct)
# create the geometry
check_err(lgdal.OGR_F_SetGeometry(feat, ogr_geom._ptr))
else:
# Case where geometry object is not found because of null
# value for field effectively looses whole record in shapefile
# if geometry does not exist
pass
# creat the feature in the layer.
check_err(lgdal.OGR_L_SetFeature(layer, feat))
# Cleaning up
check_err(lgdal.OGR_L_SyncToDisk(layer))
lgdal.OGR_DS_Destroy(ds)
lgdal.OGRCleanupAll()
def write_with_ctypes_bindings(self, tmp_name, queryset, geo_field):
""" Write a shapefile out to a file from a geoqueryset.
Uses GeoDjangos ctypes wrapper to ogr in libgdal.
"""
# Get the shapefile driver
dr = Driver('ESRI Shapefile')
# Creating the datasource
ds = lgdal.OGR_Dr_CreateDataSource(dr._ptr, tmp_name, None)
if ds is None:
raise Exception('Could not create file!')
# Get the right geometry type number for ogr
if hasattr(geo_field, 'geom_type'):
ogr_type = OGRGeomType(geo_field.geom_type).num
else:
ogr_type = OGRGeomType(geo_field._geom).num
# Set up the native spatial reference of the geometry field using the srid
if hasattr(geo_field, 'srid'):
native_srs = SpatialReference(geo_field.srid)
else:
native_srs = SpatialReference(geo_field._srid)
if self.proj_transform:
output_srs = SpatialReference(self.proj_transform)
else:
output_srs = native_srs
# create the layer
# this is crashing python26 on osx and ubuntu
layer = lgdal.OGR_DS_CreateLayer(ds, 'lyr', output_srs._ptr, ogr_type,
None)
# Create the fields
attributes = self.get_attributes()
for field in attributes:
fld = lgdal.OGR_Fld_Create(str(field.name), 4)
added = lgdal.OGR_L_CreateField(layer, fld, 0)
check_err(added)
# Getting the Layer feature definition.
feature_def = lgdal.OGR_L_GetLayerDefn(layer)
# Loop through queryset creating features
for item in self.queryset:
feat = lgdal.OGR_F_Create(feature_def)
# For now, set all fields as strings
# TODO: catch model types and convert to ogr fields
# http://www.gdal.org/ogr/classOGRFeature.html
# OGR_F_SetFieldDouble
#OFTReal => FloatField DecimalField
# OGR_F_SetFieldInteger
#OFTInteger => IntegerField
#OGR_F_SetFieldStrin
#OFTString => CharField
# OGR_F_SetFieldDateTime()
#OFTDateTime => DateTimeField
#OFTDate => TimeField
#OFTDate => DateField
for idx, field in enumerate(attributes):
value = getattr(item, field.name)
try:
string_value = str(value)
except UnicodeEncodeError as e:
# pass for now....
# http://trac.osgeo.org/gdal/ticket/882
string_value = ''
lgdal.OGR_F_SetFieldString(feat, idx, string_value)
# Transforming & setting the geometry
geom = getattr(item, geo_field.name)
# if requested we transform the input geometry
# to match the shapefiles projection 'to-be'
if geom:
ogr_geom = OGRGeometry(geom.wkt, output_srs)
if self.proj_transform:
ct = CoordTransform(native_srs, output_srs)
ogr_geom.transform(ct)
# create the geometry
check_err(lgdal.OGR_F_SetGeometry(feat, ogr_geom._ptr))
else:
# Case where geometry object is not found because of null value for field
# effectively looses whole record in shapefile if geometry does not exist
pass
# creat the feature in the layer.
check_err(lgdal.OGR_L_SetFeature(layer, feat))
# Cleaning up
check_err(lgdal.OGR_L_SyncToDisk(layer))
lgdal.OGR_DS_Destroy(ds)
lgdal.OGRCleanupAll()
