def _elevation_at_point(self):
if self._elevation is None:
request = self.context['request']
if not request.query_params.get('point'):
return None
else:
try:
x, y = [float(x) for x in request.query_params['point'].split(',')]
except ValueError:
raise ParseError()
point = Point(x, y)
self._elevation = get_elevation_at_point(point)
return self._elevation
def get_queryset(self):
if not self.request.query_params.get('point'):
return self.queryset
else:
try:
x, y = [float(x) for x in self.request.query_params['point'].split(',')]
except ValueError:
raise ParseError()
elevation = get_elevation_at_point(Point(x, y))
if elevation is None or is_masked(elevation):
return self.queryset.none()
# Elevation bands are stored in feet
return self.queryset.filter(
Q(low__lt=elevation/0.3048, high__gte=elevation/0.3048) | Q(low__isnull=True, high__isnull=True)
)