def parse_layer(self,shapefile, layername, fields_of_interest):
ds = DataSource(shapefile)
lyr = ds[0]
num_feat = lyr.num_feat
overwrite = True
if overwrite:
try:
old_lyr = Layer.objects.get(name=layername)
old_lyr.delete()
except:
pass
try:
the_layer = Layer(name=layername)
the_layer.save()
except:
raise Exception('Unable to create layer named %s' % layername)
wgs84 = SpatialReference(4326)
pctdone = 0
for feat in lyr:
try:
the_geometry = feat.geom.transform(wgs84,clone=True)
the_feature = Feature(layer=the_layer, geom=the_geometry.wkt)
the_feature.save()
except:
raise Exception('Unable to create feature')
try:
for fld in lyr.fields:
if fld in fields_of_interest or len(fields_of_interest) == 0:
the_attribute = Attribute(key=fld, value=str(feat[fld]), feature=the_feature)
the_attribute.save()
except:
raise Exception('Unable to create attribute')
oldpctdone = pctdone
pctdone = int((feat.fid * 100.) / float(num_feat))
if pctdone > oldpctdone:
print "Completed %d percent of %d features" % (pctdone, num_feat)
def parse_layer(self,rast, layername, srs):
ds = gdal.Open(rast)
if ds is None:
raise Exception("Dataset is not valid")
else:
rast = os.path.abspath(rast)
if srs:
srscmdpart = "-a_srs '%s'" % srs
else:
srscmdpart = ''
if ds.GetProjection() == '' or not ds.GetProjection():
raise Exception("Looks like the raster doesn't have a projection defined - use --srs")
# Create a new layer
overwrite = True
if overwrite:
try:
old_lyr = Layer.objects.get(name=layername)
old_lyr.delete()
except:
pass
the_layer = Layer(name=layername)
the_layer.save()
# Make a vrt copy of the dataset
vrtpath = os.path.abspath(os.path.join(settings.MEDIA_ROOT,"xyquery_rasters",layername + ".vrt"))
command = "gdal_translate %s -of VRT '%s' '%s'" % (srscmdpart, rast, vrtpath)
output = Popen(command, shell=True).communicate()[0]
ds = gdal.Open(vrtpath)
if not ds or not os.path.exists(vrtpath):
raise Exception("%s does not exist .. somthing went screwy in the gdal_translate command \n\n %s" % (vrtpath, command))
del ds
# Create a new raster model instance
the_raster = Raster(layer=the_layer, filepath=vrtpath)
the_raster.save()