303 lines
10 KiB
Python
303 lines
10 KiB
Python
import fiona
|
|
import os
|
|
import rtree
|
|
import ujson as json
|
|
|
|
from collections import OrderedDict
|
|
from shapely.geometry import Point, Polygon, MultiPolygon
|
|
from shapely.prepared import prep
|
|
from shapely.geometry.geo import mapping
|
|
|
|
DEFAULT_POLYS_FILENAME = 'polygons.geojson'
|
|
|
|
|
|
class PolygonIndex(object):
|
|
include_only_properties = None
|
|
simplify_tolerance = 0.0001
|
|
preserve_topology = True
|
|
|
|
INDEX_FILENAME = None
|
|
|
|
def __init__(self, index=None, polygons=None, save_dir=None,
|
|
index_filename=None,
|
|
include_only_properties=None):
|
|
if save_dir:
|
|
self.save_dir = save_dir
|
|
else:
|
|
self.save_dir = None
|
|
|
|
if index_filename:
|
|
self.index_path = os.path.join(save_dir or '.', index_filename)
|
|
else:
|
|
self.index_path = None
|
|
|
|
if not index and self.index_path:
|
|
self.create_index(self.index_path, overwrite=True)
|
|
elif not index:
|
|
self.create_index()
|
|
else:
|
|
self.index = index
|
|
|
|
if include_only_properties and hasattr(include_only_properties, '__contains__'):
|
|
self.include_only_properties = include_only_properties
|
|
|
|
if not polygons:
|
|
self.polygons = []
|
|
else:
|
|
self.polygons = polygons
|
|
|
|
self.i = 0
|
|
|
|
def create_index(self, index_path=None, overwrite=False):
|
|
raise NotImplementedError('Children must implement')
|
|
|
|
def index_polygon(self, polygon):
|
|
raise NotImplementedError('Children must implement')
|
|
|
|
def simplify_polygon(self, poly, simplify_tolerance=None, preserve_topology=None):
|
|
if simplify_tolerance is None:
|
|
simplify_tolerance = self.simplify_tolerance
|
|
if preserve_topology is None:
|
|
preserve_topology = self.preserve_topology
|
|
return poly.simplify(simplify_tolerance, preserve_topology=preserve_topology)
|
|
|
|
def add_polygon(self, poly, properties, include_only_properties=None):
|
|
if include_only_properties is not None:
|
|
properties = {k: v for k, v in properties.iteritems() if k in include_only_properties}
|
|
self.polygons.append((properties, prep(poly)))
|
|
self.i += 1
|
|
|
|
@classmethod
|
|
def create_from_shapefiles(cls, inputs, output_dir,
|
|
index_filename=None,
|
|
polys_filename=DEFAULT_POLYS_FILENAME,
|
|
include_only_properties=None):
|
|
index = cls(save_dir=output_dir, index_filename=index_filename or cls.INDEX_FILENAME)
|
|
for input_file in inputs:
|
|
if include_only_properties is not None:
|
|
include_props = include_only_properties.get(input_file, cls.include_only_properties)
|
|
else:
|
|
include_props = cls.include_only_properties
|
|
|
|
f = fiona.open(input_file)
|
|
|
|
index.add_geojson_like_file(f)
|
|
|
|
return index
|
|
|
|
@classmethod
|
|
def fix_polygon(cls, poly):
|
|
'''
|
|
Coerce to valid polygon
|
|
'''
|
|
if not poly.is_valid:
|
|
poly = poly.buffer(0)
|
|
if not poly.is_valid:
|
|
return None
|
|
return poly
|
|
|
|
@classmethod
|
|
def to_polygon(cls, coords):
|
|
'''
|
|
Create shapely polygon from list of coordinate tuples if valid
|
|
'''
|
|
if not coords or len(coords) < 3:
|
|
return None
|
|
poly = Polygon(coords)
|
|
return cls.fix_polygon(poly)
|
|
|
|
def add_geojson_like_record(self, rec, include_only_properties=None):
|
|
if not rec or not rec.get('geometry') or 'type' not in rec['geometry']:
|
|
return
|
|
poly_type = rec['geometry']['type']
|
|
if poly_type == 'Polygon':
|
|
coords = rec['geometry']['coordinates'][0]
|
|
poly = self.to_polygon(coords)
|
|
if poly is None or not poly.bounds or len(poly.bounds) != 4:
|
|
return
|
|
self.index_polygon(poly)
|
|
self.add_polygon(poly, rec['properties'], include_only_properties=include_only_properties)
|
|
elif poly_type == 'MultiPolygon':
|
|
polys = []
|
|
poly_coords = rec['geometry']['coordinates']
|
|
for coords in poly_coords:
|
|
poly = self.to_polygon(coords[0])
|
|
if poly is None or not poly.bounds or len(poly.bounds) != 4:
|
|
continue
|
|
polys.append(poly)
|
|
self.index_polygon(poly)
|
|
|
|
self.add_polygon(MultiPolygon(polys), rec['properties'], include_only_properties=include_only_properties)
|
|
else:
|
|
return
|
|
|
|
def add_geojson_like_file(self, f, include_only_properties=None):
|
|
'''
|
|
Add either GeoJSON or a shapefile record to the index
|
|
'''
|
|
|
|
for rec in f:
|
|
self.add_geojson_like_record(rec, include_only_properties=include_only_properties)
|
|
|
|
@classmethod
|
|
def create_from_geojson_files(cls, inputs, output_dir,
|
|
index_filename=None,
|
|
polys_filename=DEFAULT_POLYS_FILENAME,
|
|
include_only_properties=None):
|
|
index = cls(save_dir=output_dir, index_filename=index_filename or cls.INDEX_FILENAME)
|
|
for input_file in inputs:
|
|
if include_only_properties is not None:
|
|
include_props = include_only_properties.get(input_file, cls.include_only_properties)
|
|
else:
|
|
include_props = cls.include_only_properties
|
|
|
|
f = json.load(open(input_file))
|
|
|
|
index.add_geojson_like_file(f['features'], include_only_properties=include_props)
|
|
|
|
return index
|
|
|
|
def save(self, polys_filename=DEFAULT_POLYS_FILENAME):
|
|
self.save_polygons(os.path.join(self.save_dir, polys_filename))
|
|
self.save_index(index_filename=self.index_path)
|
|
|
|
def save_polygons(self, out_filename):
|
|
out = open(out_filename, 'w')
|
|
for props, poly in self.polygons:
|
|
feature = {
|
|
'type': 'Feature',
|
|
'geometry': mapping(poly.context),
|
|
'properties': props
|
|
}
|
|
out.write(json.dumps(feature) + u'\n')
|
|
|
|
def save_index(self):
|
|
raise NotImplementedError('Children must implement')
|
|
|
|
@classmethod
|
|
def load_polygons(cls, filename):
|
|
f = open(filename)
|
|
polygons = []
|
|
for line in f:
|
|
feature = json.loads(line.rstrip())
|
|
poly_type = feature['geometry']['type']
|
|
|
|
if poly_type == 'Polygon':
|
|
poly = Polygon(feature['geometry']['coordinates'][0])
|
|
polygons.append((feature['properties'], prep(poly)))
|
|
elif poly_type == 'MultiPolygon':
|
|
polys = []
|
|
for coords in feature['geometry']['coordinates']:
|
|
poly = Polygon(coords[0])
|
|
polys.append(poly)
|
|
|
|
polygons.append((feature['properties'], prep(MultiPolygon(polys))))
|
|
return polygons
|
|
|
|
|
|
@classmethod
|
|
def load_index(cls, d, index_name=None):
|
|
raise NotImplementedError('Children must implement')
|
|
|
|
|
|
@classmethod
|
|
def load(cls, d, index_name=None, polys_filename=DEFAULT_POLYS_FILENAME):
|
|
index = cls.load_index(d, index_name=index_name or cls.INDEX_FILENAME)
|
|
polys = cls.load_polygons(os.path.join(d, polys_filename))
|
|
return cls(index=index, polygons=polys, save_dir=d)
|
|
|
|
|
|
def get_candidate_polygons(self, lat, lon):
|
|
raise NotImplementedError('Children must implement')
|
|
|
|
def point_in_poly(self, lat, lon, return_all=False):
|
|
polys = self.get_candidate_polygons(lat, lon)
|
|
pt = Point(lon, lat)
|
|
containing = None
|
|
if return_all:
|
|
containing = []
|
|
for i in polys:
|
|
props, poly = self.polygons[i]
|
|
contains = poly.contains(pt)
|
|
if contains and not return_all:
|
|
return props
|
|
elif contains:
|
|
containing.append(props)
|
|
return containing
|
|
|
|
|
|
class RTreePolygonIndex(PolygonIndex):
|
|
INDEX_FILENAME = 'index.rtree'
|
|
|
|
def create_index(self, index_path=None, overwrite=False):
|
|
if index_path:
|
|
self.index = rtree.index.Index(index_path, overwrite=overwrite)
|
|
else:
|
|
self.index = rtree.index.Index()
|
|
|
|
def index_polygon(self, polygon):
|
|
self.index.insert(self.i, polygon.bounds)
|
|
|
|
def get_candidate_polygons(self, lat, lon):
|
|
return OrderedDict.fromkeys(self.index.intersection((lon, lat, lon, lat))).keys()
|
|
|
|
def save_index(self):
|
|
# need to close index before loading it
|
|
self.index.close()
|
|
|
|
@classmethod
|
|
def load_index(cls, d, index_name=None):
|
|
return rtree.index.Index(os.path.join(d, index_name or cls.INDEX_FILENAME))
|
|
|
|
|
|
class GeohashPolygonIndex(PolygonIndex):
|
|
# Reference: https://www.elastic.co/guide/en/elasticsearch/guide/current/geohashes.html
|
|
GEOHASH_PRECISIONS = [
|
|
(7, 152.8 ** 2),
|
|
(6, 1200.0 * 610.0),
|
|
(5, 4900.0 * 4900.0),
|
|
(4, 39000.0 * 19500.0),
|
|
(3, 156000.0 * 156000.0),
|
|
(2, 1251000.0 * 625000.0),
|
|
]
|
|
|
|
INDEX_FILENAME = 'index.json'
|
|
|
|
def create_index(self, index_path=None, overwrite=False):
|
|
self.index = defaultdict(list)
|
|
|
|
def index_point(self, lat, lon, geohash_level):
|
|
code = geohash.encode(lat, lon)[:geohash_level]
|
|
|
|
for key in [code] + geohash.neighbors(code):
|
|
self.index[key].append(self.i)
|
|
|
|
def index_polygon(self, polygon):
|
|
poly_area = polygon_bounding_box_area(polygon)
|
|
for geohash_level, area in self.GEOHASH_PRECISIONS:
|
|
if area * 9.0 >= poly_area:
|
|
break
|
|
|
|
bbox = polygon.bounds
|
|
lat, lon = (bbox[1] + bbox[3]) / 2.0, (bbox[0] + bbox[2]) / 2.0
|
|
self.index_point(lat, lon, geohash_level)
|
|
|
|
def get_candidate_polygons(self, lat, lon, all_levels=False):
|
|
candidates = []
|
|
code = geohash.encode(lat, lon)
|
|
for level, area in self.GEOHASH_PRECISIONS:
|
|
indices = self.index.get(code[:level])
|
|
if not indices:
|
|
continue
|
|
candidates.extend(indices)
|
|
if not all_levels:
|
|
break
|
|
return candidates
|
|
|
|
def save_index(self):
|
|
json.dump(self.index, open(self.index_path, 'w'))
|
|
|
|
@classmethod
|
|
def load_index(cls, d, index_name=None):
|
|
return json.load(open(os.path.join(d, index_name or cls.INDEX_FILENAME)))
|