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Nominatim/src/nominatim_api/search/db_searches/postcode_search.py
2025-12-30 15:20:46 +01:00

108 lines
3.9 KiB
Python

# SPDX-License-Identifier: GPL-3.0-or-later
#
# This file is part of Nominatim. (https://nominatim.org)
#
# Copyright (C) 2025 by the Nominatim developer community.
# For a full list of authors see the git log.
"""
Implementation of search for a postcode.
"""
import sqlalchemy as sa
from . import base
from ...typing import SaBind, SaExpression
from ...sql.sqlalchemy_types import Geometry, IntArray
from ...connection import SearchConnection
from ...types import SearchDetails
from ... import results as nres
from ..db_search_fields import SearchData
LIMIT_PARAM: SaBind = sa.bindparam('limit')
VIEWBOX_PARAM: SaBind = sa.bindparam('viewbox', type_=Geometry)
VIEWBOX2_PARAM: SaBind = sa.bindparam('viewbox2', type_=Geometry)
NEAR_PARAM: SaBind = sa.bindparam('near', type_=Geometry)
class PostcodeSearch(base.AbstractSearch):
""" Search for a postcode.
"""
def __init__(self, extra_penalty: float, sdata: SearchData) -> None:
super().__init__(sdata.penalty + extra_penalty)
self.countries = sdata.countries
self.postcodes = sdata.postcodes
self.lookups = sdata.lookups
self.rankings = sdata.rankings
async def lookup(self, conn: SearchConnection,
details: SearchDetails) -> nres.SearchResults:
""" Find results for the search in the database.
"""
t = conn.t.postcode
pcs = self.postcodes.values
sql = sa.select(t.c.place_id, t.c.parent_place_id, t.c.osm_id,
t.c.rank_search, t.c.postcode, t.c.country_code,
t.c.centroid)\
.where(t.c.postcode.in_(pcs))
if details.geometry_output:
sql = base.add_geometry_columns(sql, t.c.geometry, details)
penalty: SaExpression = sa.literal(self.penalty)
if details.viewbox is not None and not details.bounded_viewbox:
penalty += sa.case((t.c.geometry.intersects(VIEWBOX_PARAM), 0.0),
(t.c.geometry.intersects(VIEWBOX2_PARAM), 0.5),
else_=1.0)
if details.near is not None:
sql = sql.order_by(t.c.centroid.ST_Distance(NEAR_PARAM))
sql = base.filter_by_area(sql, t, details)
if self.countries:
sql = sql.where(t.c.country_code.in_(self.countries.values))
if details.excluded:
sql = sql.where(base.exclude_places(t))
if self.lookups:
assert len(self.lookups) == 1
tsearch = conn.t.search_name
sql = sql.where(tsearch.c.place_id == t.c.parent_place_id)\
.where((tsearch.c.name_vector + tsearch.c.nameaddress_vector)
.contains(sa.type_coerce(self.lookups[0].tokens,
IntArray)))
# Do NOT add rerank penalties based on the address terms.
# The standard rerank penalty only checks the address vector
# while terms may appear in name and address vector. This would
# lead to overly high penalties.
# We assume that a postcode is precise enough to not require
# additional full name matches.
penalty += sa.case(*((t.c.postcode == v, p) for v, p in self.postcodes),
else_=1.0)
sql = sql.add_columns(penalty.label('accuracy'))
sql = sql.order_by('accuracy').limit(LIMIT_PARAM)
bind_params = {
'limit': details.max_results,
'viewbox': details.viewbox,
'viewbox2': details.viewbox_x2,
'near': details.near,
'near_radius': details.near_radius,
'excluded': details.excluded
}
results = nres.SearchResults()
for row in await conn.execute(sql, bind_params):
result = nres.create_from_postcode_row(row, nres.SearchResult)
result.accuracy = row.accuracy
results.append(result)
return results