nominatim/db/sqlalchemy_types.py

   1 # SPDX-License-Identifier: GPL-3.0-or-later
   2 #
   3 # This file is part of Nominatim. (https://nominatim.org)
   4 #
   5 # Copyright (C) 2023 by the Nominatim developer community.
   6 # For a full list of authors see the git log.
   7 """
   8 Custom types for SQLAlchemy.
   9 """
  10 from typing import Callable, Any
  11
  12 import sqlalchemy as sa
  13 import sqlalchemy.types as types
  14
  15 from nominatim.typing import SaColumn
  16
  17 class Geometry(types.UserDefinedType[Any]):
  18     """ Simplified type decorator for PostGIS geometry. This type
  19         only supports geometries in 4326 projection.
  20     """
  21     cache_ok = True
  22
  23     def __init__(self, subtype: str = 'Geometry'):
  24         self.subtype = subtype
  25
  26
  27     def get_col_spec(self) -> str:
  28         return f'GEOMETRY({self.subtype}, 4326)'
  29
  30
  31     def bind_processor(self, dialect: sa.Dialect) -> Callable[[Any], str]:
  32         def process(value: Any) -> str:
  33             assert isinstance(value, str)
  34             return value
  35         return process
  36
  37
  38     def result_processor(self, dialect: sa.Dialect, coltype: object) -> Callable[[Any], str]:
  39         def process(value: Any) -> str:
  40             assert isinstance(value, str)
  41             return value
  42         return process
  43
  44
  45     def bind_expression(self, bindvalue: sa.BindParameter[Any]) -> SaColumn:
  46         return sa.func.ST_GeomFromText(bindvalue, type_=self)
  47
  48
  49     class comparator_factory(types.UserDefinedType.Comparator):
  50
  51         def is_line_like(self) -> SaColumn:
  52             return sa.func.ST_GeometryType(self, type_=sa.String).in_(('ST_LineString',
  53                                                                        'ST_MultiLineString'))
  54
  55         def is_area(self) -> SaColumn:
  56             return sa.func.ST_GeometryType(self, type_=sa.String).in_(('ST_Polygon',
  57                                                                        'ST_MultiPolygon'))
  58
  59
  60         def ST_DWithin(self, other: SaColumn, distance: SaColumn) -> SaColumn:
  61             return sa.func.ST_DWithin(self, other, distance, type_=sa.Float)
  62
  63
  64         def ST_Distance(self, other: SaColumn) -> SaColumn:
  65             return sa.func.ST_Distance(self, other, type_=sa.Float)
  66
  67
  68         def ST_Contains(self, other: SaColumn) -> SaColumn:
  69             return sa.func.ST_Contains(self, other, type_=sa.Float)
  70
  71
  72         def ST_ClosestPoint(self, other: SaColumn) -> SaColumn:
  73             return sa.func.ST_ClosestPoint(self, other, type_=Geometry)
  74
  75
  76         def ST_Buffer(self, other: SaColumn) -> SaColumn:
  77             return sa.func.ST_Buffer(self, other, type_=Geometry)
  78
  79
  80         def ST_Expand(self, other: SaColumn) -> SaColumn:
  81             return sa.func.ST_Expand(self, other, type_=Geometry)
  82
  83
  84         def ST_Centroid(self) -> SaColumn:
  85             return sa.func.ST_Centroid(self, type_=Geometry)
  86
  87
  88         def ST_LineInterpolatePoint(self, other: SaColumn) -> SaColumn:
  89             return sa.func.ST_LineInterpolatePoint(self, other, type_=Geometry)
  90
  91
  92         def ST_LineLocatePoint(self, other: SaColumn) -> SaColumn:
  93             return sa.func.ST_LineLocatePoint(self, other, type_=sa.Float)