Nominatim/nominatim/data/postcode_format.py
2022-07-18 09:47:57 +02:00

115 lines
4.3 KiB
Python

# SPDX-License-Identifier: GPL-2.0-only
#
# This file is part of Nominatim. (https://nominatim.org)
#
# Copyright (C) 2022 by the Nominatim developer community.
# For a full list of authors see the git log.
"""
Functions for formatting postcodes according to their country-specific
format.
"""
from typing import Any, Mapping, Optional, Set, Match
import re
from nominatim.errors import UsageError
from nominatim.data import country_info
class CountryPostcodeMatcher:
""" Matches and formats a postcode according to a format definition
of the given country.
"""
def __init__(self, country_code: str, config: Mapping[str, Any]) -> None:
if 'pattern' not in config:
raise UsageError("Field 'pattern' required for 'postcode' "
f"for country '{country_code}'")
pc_pattern = config['pattern'].replace('d', '[0-9]').replace('l', '[A-Z]')
self.norm_pattern = re.compile(f'\\s*(?:{country_code.upper()}[ -]?)?(.*)\\s*')
self.pattern = re.compile(pc_pattern)
self.output = config.get('output', r'\g<0>')
def match(self, postcode: str) -> Optional[Match[str]]:
""" Match the given postcode against the postcode pattern for this
matcher. Returns a `re.Match` object if the match was successful
and None otherwise.
"""
# Upper-case, strip spaces and leading country code.
normalized = self.norm_pattern.fullmatch(postcode.upper())
if normalized:
return self.pattern.fullmatch(normalized.group(1))
return None
def normalize(self, match: Match[str]) -> str:
""" Return the default format of the postcode for the given match.
`match` must be a `re.Match` object previously returned by
`match()`
"""
return match.expand(self.output)
class PostcodeFormatter:
""" Container for different postcode formats of the world and
access functions.
"""
def __init__(self) -> None:
# Objects without a country code can't have a postcode per definition.
self.country_without_postcode: Set[Optional[str]] = {None}
self.country_matcher = {}
self.default_matcher = CountryPostcodeMatcher('', {'pattern': '.*'})
for ccode, prop in country_info.iterate('postcode'):
if prop is False:
self.country_without_postcode.add(ccode)
elif isinstance(prop, dict):
self.country_matcher[ccode] = CountryPostcodeMatcher(ccode, prop)
else:
raise UsageError(f"Invalid entry 'postcode' for country '{ccode}'")
def set_default_pattern(self, pattern: str) -> None:
""" Set the postcode match pattern to use, when a country does not
have a specific pattern.
"""
self.default_matcher = CountryPostcodeMatcher('', {'pattern': pattern})
def get_matcher(self, country_code: Optional[str]) -> Optional[CountryPostcodeMatcher]:
""" Return the CountryPostcodeMatcher for the given country.
Returns None if the country doesn't have a postcode and the
default matcher if there is no specific matcher configured for
the country.
"""
if country_code in self.country_without_postcode:
return None
assert country_code is not None
return self.country_matcher.get(country_code, self.default_matcher)
def match(self, country_code: Optional[str], postcode: str) -> Optional[Match[str]]:
""" Match the given postcode against the postcode pattern for this
matcher. Returns a `re.Match` object if the country has a pattern
and the match was successful or None if the match failed.
"""
if country_code in self.country_without_postcode:
return None
assert country_code is not None
return self.country_matcher.get(country_code, self.default_matcher).match(postcode)
def normalize(self, country_code: str, match: Match[str]) -> str:
""" Return the default format of the postcode for the given match.
`match` must be a `re.Match` object previously returned by
`match()`
"""
return self.country_matcher.get(country_code, self.default_matcher).normalize(match)