29 lines
785 B
Python
29 lines
785 B
Python
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"""
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A collection of utility routines and classes used by the spatial
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backends.
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"""
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class SpatialOperator:
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"""
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Class encapsulating the behavior specific to a GIS operation (used by lookups).
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"""
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sql_template = None
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def __init__(self, op=None, func=None):
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self.op = op
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self.func = func
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@property
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def default_template(self):
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if self.func:
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return "%(func)s(%(lhs)s, %(rhs)s)"
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else:
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return "%(lhs)s %(op)s %(rhs)s"
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def as_sql(self, connection, lookup, template_params, sql_params):
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sql_template = self.sql_template or lookup.sql_template or self.default_template
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template_params.update({"op": self.op, "func": self.func})
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return sql_template % template_params, sql_params
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