def write_geojson(features, outFileName, srs=None):
features = geo_features(features)
with open(outFileName,'w') as f:
# FeatureCollection header
f.write('{\n"type": "FeatureCollection",\n')
# spatial ref spec
if srs:
f.write('"crs": ')
json.dump(spatialref.geojson_crs(srs),f,indent=2)
f.write(',\n')
# features header
f.write('"features": [\n')
# features
for feature in features:
geojson.dump(feature,f,indent=2)
if feature != features[-1]: f.write(',')
f.write('\n\n')
# close features
f.write(']\n')
# close FeatureCollection
f.write('}\n')
def geo_feature_collection(geo, srs=None):
"""return a feature collection for multiple types of input.
Add coordinate ref system, if srs arg given."""
# handle geo_interface
try: geo = geo.__geo_interface__
except AttributeError: pass
# input is already a feature collection?
type = None
try: type = geo['type']
except: pass
isfc = (type=='FeatureCollection')
if isfc:
fc = geo
else:
features = geo_features(geo)
fc = geojson.FeatureCollection(features)
# add coordinate reference system, if srs supplied
if srs: fc.crs = spatialref.geojson_crs(srs)
return fc
