--- /dev/null
+# 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.
+"""
+Parser for configuration for variants.
+"""
+from collections import defaultdict, namedtuple
+import itertools
+import re
+
+from icu import Transliterator
+
+from nominatim.config import flatten_config_list
+from nominatim.errors import UsageError
+
+ICUVariant = namedtuple('ICUVariant', ['source', 'replacement'])
+
+def get_variant_config(rules, normalization_rules):
+ """ Convert the variant definition from the configuration into
+ replacement sets.
+
+ Returns a tuple containing the replacement set and the list of characters
+ used in the replacements.
+ """
+ immediate = defaultdict(list)
+ chars = set()
+
+ if rules:
+ vset = set()
+ rules = flatten_config_list(rules, 'variants')
+
+ vmaker = _VariantMaker(normalization_rules)
+
+ for section in rules:
+ for rule in (section.get('words') or []):
+ vset.update(vmaker.compute(rule))
+
+ # Intermediate reorder by source. Also compute required character set.
+ for variant in vset:
+ if variant.source[-1] == ' ' and variant.replacement[-1] == ' ':
+ replstr = variant.replacement[:-1]
+ else:
+ replstr = variant.replacement
+ immediate[variant.source].append(replstr)
+ chars.update(variant.source)
+
+ return list(immediate.items()), ''.join(chars)
+
+
+class _VariantMaker:
+ """ Generater for all necessary ICUVariants from a single variant rule.
+
+ All text in rules is normalized to make sure the variants match later.
+ """
+
+ def __init__(self, norm_rules):
+ self.norm = Transliterator.createFromRules("rule_loader_normalization",
+ norm_rules)
+
+
+ def compute(self, rule):
+ """ Generator for all ICUVariant tuples from a single variant rule.
+ """
+ parts = re.split(r'(\|)?([=-])>', rule)
+ if len(parts) != 4:
+ raise UsageError("Syntax error in variant rule: " + rule)
+
+ decompose = parts[1] is None
+ src_terms = [self._parse_variant_word(t) for t in parts[0].split(',')]
+ repl_terms = (self.norm.transliterate(t).strip() for t in parts[3].split(','))
+
+ # If the source should be kept, add a 1:1 replacement
+ if parts[2] == '-':
+ for src in src_terms:
+ if src:
+ for froms, tos in _create_variants(*src, src[0], decompose):
+ yield ICUVariant(froms, tos)
+
+ for src, repl in itertools.product(src_terms, repl_terms):
+ if src and repl:
+ for froms, tos in _create_variants(*src, repl, decompose):
+ yield ICUVariant(froms, tos)
+
+
+ def _parse_variant_word(self, name):
+ name = name.strip()
+ match = re.fullmatch(r'([~^]?)([^~$^]*)([~$]?)', name)
+ if match is None or (match.group(1) == '~' and match.group(3) == '~'):
+ raise UsageError("Invalid variant word descriptor '{}'".format(name))
+ norm_name = self.norm.transliterate(match.group(2)).strip()
+ if not norm_name:
+ return None
+
+ return norm_name, match.group(1), match.group(3)
+
+
+_FLAG_MATCH = {'^': '^ ',
+ '$': ' ^',
+ '': ' '}
+
+
+def _create_variants(src, preflag, postflag, repl, decompose):
+ if preflag == '~':
+ postfix = _FLAG_MATCH[postflag]
+ # suffix decomposition
+ src = src + postfix
+ repl = repl + postfix
+
+ yield src, repl
+ yield ' ' + src, ' ' + repl
+
+ if decompose:
+ yield src, ' ' + repl
+ yield ' ' + src, repl
+ elif postflag == '~':
+ # prefix decomposition
+ prefix = _FLAG_MATCH[preflag]
+ src = prefix + src
+ repl = prefix + repl
+
+ yield src, repl
+ yield src + ' ', repl + ' '
+
+ if decompose:
+ yield src, repl + ' '
+ yield src + ' ', repl
+ else:
+ prefix = _FLAG_MATCH[preflag]
+ postfix = _FLAG_MATCH[postflag]
+
+ yield prefix + src + postfix, prefix + repl + postfix
"""
Generic processor for names that creates abbreviation variants.
"""
-from collections import defaultdict, namedtuple
import itertools
-import re
-from icu import Transliterator
import datrie
-from nominatim.config import flatten_config_list
-from nominatim.errors import UsageError
+from nominatim.tokenizer.token_analysis.config_variants import get_variant_config
### Configuration section
-ICUVariant = namedtuple('ICUVariant', ['source', 'replacement'])
-
def configure(rules, normalization_rules):
""" Extract and preprocess the configuration for this module.
"""
config = {}
- config['replacements'], config['chars'] = _get_variant_config(rules.get('variants'),
- normalization_rules)
+ config['replacements'], config['chars'] = get_variant_config(rules.get('variants'),
+ normalization_rules)
config['variant_only'] = rules.get('mode', '') == 'variant-only'
return config
-def _get_variant_config(rules, normalization_rules):
- """ Convert the variant definition from the configuration into
- replacement sets.
- """
- immediate = defaultdict(list)
- chars = set()
-
- if rules:
- vset = set()
- rules = flatten_config_list(rules, 'variants')
-
- vmaker = _VariantMaker(normalization_rules)
-
- for section in rules:
- for rule in (section.get('words') or []):
- vset.update(vmaker.compute(rule))
-
- # Intermediate reorder by source. Also compute required character set.
- for variant in vset:
- if variant.source[-1] == ' ' and variant.replacement[-1] == ' ':
- replstr = variant.replacement[:-1]
- else:
- replstr = variant.replacement
- immediate[variant.source].append(replstr)
- chars.update(variant.source)
-
- return list(immediate.items()), ''.join(chars)
-
-
-class _VariantMaker:
- """ Generater for all necessary ICUVariants from a single variant rule.
-
- All text in rules is normalized to make sure the variants match later.
- """
-
- def __init__(self, norm_rules):
- self.norm = Transliterator.createFromRules("rule_loader_normalization",
- norm_rules)
-
-
- def compute(self, rule):
- """ Generator for all ICUVariant tuples from a single variant rule.
- """
- parts = re.split(r'(\|)?([=-])>', rule)
- if len(parts) != 4:
- raise UsageError("Syntax error in variant rule: " + rule)
-
- decompose = parts[1] is None
- src_terms = [self._parse_variant_word(t) for t in parts[0].split(',')]
- repl_terms = (self.norm.transliterate(t).strip() for t in parts[3].split(','))
-
- # If the source should be kept, add a 1:1 replacement
- if parts[2] == '-':
- for src in src_terms:
- if src:
- for froms, tos in _create_variants(*src, src[0], decompose):
- yield ICUVariant(froms, tos)
-
- for src, repl in itertools.product(src_terms, repl_terms):
- if src and repl:
- for froms, tos in _create_variants(*src, repl, decompose):
- yield ICUVariant(froms, tos)
-
-
- def _parse_variant_word(self, name):
- name = name.strip()
- match = re.fullmatch(r'([~^]?)([^~$^]*)([~$]?)', name)
- if match is None or (match.group(1) == '~' and match.group(3) == '~'):
- raise UsageError("Invalid variant word descriptor '{}'".format(name))
- norm_name = self.norm.transliterate(match.group(2)).strip()
- if not norm_name:
- return None
-
- return norm_name, match.group(1), match.group(3)
-
-
-_FLAG_MATCH = {'^': '^ ',
- '$': ' ^',
- '': ' '}
-
-
-def _create_variants(src, preflag, postflag, repl, decompose):
- if preflag == '~':
- postfix = _FLAG_MATCH[postflag]
- # suffix decomposition
- src = src + postfix
- repl = repl + postfix
-
- yield src, repl
- yield ' ' + src, ' ' + repl
-
- if decompose:
- yield src, ' ' + repl
- yield ' ' + src, repl
- elif postflag == '~':
- # prefix decomposition
- prefix = _FLAG_MATCH[preflag]
- src = prefix + src
- repl = prefix + repl
-
- yield src, repl
- yield src + ' ', repl + ' '
-
- if decompose:
- yield src, repl + ' '
- yield src + ' ', repl
- else:
- prefix = _FLAG_MATCH[preflag]
- postfix = _FLAG_MATCH[postflag]
-
- yield prefix + src + postfix, prefix + repl + postfix
-
-
### Analysis section
def create(transliterator, config):