def _distance_determine_aggregation_depth(self, valid_tile_tuples):
"""Uses distance between to recalibrate aggregation depth in tiles"""
if len(valid_tile_tuples) < 2:
return self.default_aggregation_depth
lons = []
lats = []
gm = GlobalMercator()
for tile, _ in valid_tile_tuples:
geo_coords = gm.quadtree_to_geojson_lon_lat(tile)
# Remember geojson ordering of the coordinates (lon, lat)
lons.append(geo_coords[0])
lats.append(geo_coords[1])
max_distance = gm.distance_on_unit_sphere(
min(lats),
min(lons),
max(lats),
max(lons),
)
# Converts the maximum distance between points into a zoom level
# appropriate for tile aggregation. Seems to work well.
return gm.ZoomForPixelSize(max_distance) + 3
def make_geotile_facet_options(self, solr_json):
"""Makes geographic tile facets from a solr_json response"""
geotile_path_keys = (configs.FACETS_SOLR_ROOT_PATH_KEYS +
['discovery_geotile'])
geotile_val_count_list = utilities.get_dict_path_value(
geotile_path_keys, solr_json, default=[])
if not len(geotile_val_count_list):
return None
# Make the list of tile, count tuples.
options_tuples = utilities.get_facet_value_count_tuples(
geotile_val_count_list)
if not len(options_tuples):
return None
valid_tile_tuples = self._make_valid_options_tile_tuples(
options_tuples)
if not len(valid_tile_tuples):
# None of the chronological tiles are valid
# given the query requirements.
return None
# Determine the aggregation depth needed to group geotiles
# together into a reasonable number of options.
self._get_tile_aggregation_depth(valid_tile_tuples)
# Determine the min tile depth. We need to return this to
# the client so the client knows not to over-zoom.
tile_lens = [len(tile) for tile, _ in valid_tile_tuples]
self.min_depth = min(tile_lens)
# Get the client's requested feature type for the geotile
# facets.
feature_type = utilities.get_request_param_value(
self.request_dict,
param='geo-facet-type',
default=self.default_tile_feature_type,
as_list=False,
solr_escape=False,
)
if feature_type not in self.valid_tile_feature_types:
# If the requested feature type is not in the
# valid list of feature types, just use the default.
feature_type = self.default_tile_feature_type
aggregate_tiles = {}
for tile, count in valid_tile_tuples:
# Now aggregate the tiles.
trim_tile_key = tile[:self.default_aggregation_depth]
if trim_tile_key not in aggregate_tiles:
# Make the aggregate tile with a count
# of zero
aggregate_tiles[trim_tile_key] = 0
aggregate_tiles[trim_tile_key] += count
options = []
for tile, count in aggregate_tiles.items():
sl = SearchLinks(request_dict=copy.deepcopy(self.request_dict),
base_search_url=self.base_search_url)
# Remove non search related params.
sl.remove_non_query_params()
# Update the request dict for this facet option.
sl.replace_param_value(
'disc-geotile',
match_old_value=None,
new_value=tile,
)
urls = sl.make_urls_from_request_dict()
if urls['html'] == self.current_filters_url:
# The new URL matches our current filter
# url, so don't add this facet option.
continue
option = LastUpdatedOrderedDict()
option['id'] = urls['html']
option['json'] = urls['json']
option['count'] = count
option['type'] = 'Feature'
option['category'] = 'oc-api:geo-facet'
# Add some general chronology information to the
# geospatial tile.
option = self._add_when_object_to_feature_option(
tile,
option,
)
gm = GlobalMercator()
if feature_type == 'Polygon':
# Get polygon coordinates (a list of lists)
geo_coords = gm.quadtree_to_geojson_poly_coords(tile)
elif feature_type == 'Point':
# Get point coordinates (a list of lon,lat values)
geo_coords = gm.quadtree_to_geojson_lon_lat(tile)
else:
# We shouldn't be here!
continue
# Add the geometry object to the facet option.
geometry = LastUpdatedOrderedDict()
geometry['id'] = '#geo-disc-tile-geom-{}'.format(tile)
geometry['type'] = feature_type
geometry['coordinates'] = geo_coords
option['geometry'] = geometry
properties = LastUpdatedOrderedDict()
properties['id'] = '#geo-disc-tile-{}'.format(tile)
properties['href'] = option['id']
properties['label'] = 'Discovery region ({})'.format(
(len(options) + 1))
properties['feature-type'] = 'discovery region (facet)'
properties['count'] = count
properties['early bce/ce'] = self.min_date
properties['late bce/ce'] = self.max_date
option['properties'] = properties
options.append(option)
return options
