1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
"""
A collection of utility routines and classes used by the spatial
backends.
"""
class SpatialOperation(object):
"""
Base class for generating spatial SQL.
"""
sql_template = '%(geo_col)s %(operator)s %(geometry)s'
def __init__(self, function='', operator='', result='', **kwargs):
self.function = function
self.operator = operator
self.result = result
self.extra = kwargs
def as_sql(self, geo_col, geometry='%s'):
return self.sql_template % self.params(geo_col, geometry), []
def params(self, geo_col, geometry):
params = {'function' : self.function,
'geo_col' : geo_col,
'geometry' : geometry,
'operator' : self.operator,
'result' : self.result,
}
params.update(self.extra)
return params
class SpatialFunction(SpatialOperation):
"""
Base class for generating spatial SQL related to a function.
"""
sql_template = '%(function)s(%(geo_col)s, %(geometry)s)'
def __init__(self, func, result='', operator='', **kwargs):
# Getting the function prefix.
default = {'function' : func,
'operator' : operator,
'result' : result
}
kwargs.update(default)
super(SpatialFunction, self).__init__(**kwargs)
|
