X-Git-Url: https://git.openstreetmap.org./nominatim.git/blobdiff_plain/18554dfed767d8ef669e15014a5b0382ad8bab43..a6dab5e300de9c5664f714eb2c9290d18f01067f:/nominatim/tokenizer/icu_rule_loader.py diff --git a/nominatim/tokenizer/icu_rule_loader.py b/nominatim/tokenizer/icu_rule_loader.py index b408f1c3..035b6698 100644 --- a/nominatim/tokenizer/icu_rule_loader.py +++ b/nominatim/tokenizer/icu_rule_loader.py @@ -1,61 +1,92 @@ +# 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. """ Helper class to create ICU rules from a configuration file. """ +import importlib import io +import json import logging -import itertools -from pathlib import Path -import re - -import yaml -from icu import Transliterator +from nominatim.config import flatten_config_list +from nominatim.db.properties import set_property, get_property from nominatim.errors import UsageError -import nominatim.tokenizer.icu_variants as variants +from nominatim.tokenizer.place_sanitizer import PlaceSanitizer +from nominatim.tokenizer.icu_token_analysis import ICUTokenAnalysis +import nominatim.data.country_info LOG = logging.getLogger() -def _flatten_yaml_list(content): - if not content: - return [] - - if not isinstance(content, list): - raise UsageError("List expected in ICU yaml configuration.") - - output = [] - for ele in content: - if isinstance(ele, list): - output.extend(_flatten_yaml_list(ele)) - else: - output.append(ele) +DBCFG_IMPORT_NORM_RULES = "tokenizer_import_normalisation" +DBCFG_IMPORT_TRANS_RULES = "tokenizer_import_transliteration" +DBCFG_IMPORT_ANALYSIS_RULES = "tokenizer_import_analysis_rules" - return output - -class VariantRule: - """ Saves a single variant expansion. - - An expansion consists of the normalized replacement term and - a dicitonary of properties that describe when the expansion applies. +def _get_section(rules, section): + """ Get the section named 'section' from the rules. If the section does + not exist, raise a usage error with a meaningful message. """ + if section not in rules: + LOG.fatal("Section '%s' not found in tokenizer config.", section) + raise UsageError("Syntax error in tokenizer configuration file.") - def __init__(self, replacement, properties): - self.replacement = replacement - self.properties = properties or {} + return rules[section] class ICURuleLoader: """ Compiler for ICU rules from a tokenizer configuration file. """ - def __init__(self, configfile): - self.configfile = configfile - self.variants = set() + def __init__(self, config): + rules = config.load_sub_configuration('icu_tokenizer.yaml', + config='TOKENIZER_CONFIG') + + # Make sure country information is available to analyzers and sanitizers. + nominatim.data.country_info.setup_country_config(config) + + self.normalization_rules = self._cfg_to_icu_rules(rules, 'normalization') + self.transliteration_rules = self._cfg_to_icu_rules(rules, 'transliteration') + self.analysis_rules = _get_section(rules, 'token-analysis') + self._setup_analysis() + + # Load optional sanitizer rule set. + self.sanitizer_rules = rules.get('sanitizers', []) + + + def load_config_from_db(self, conn): + """ Get previously saved parts of the configuration from the + database. + """ + self.normalization_rules = get_property(conn, DBCFG_IMPORT_NORM_RULES) + self.transliteration_rules = get_property(conn, DBCFG_IMPORT_TRANS_RULES) + self.analysis_rules = json.loads(get_property(conn, DBCFG_IMPORT_ANALYSIS_RULES)) + self._setup_analysis() + + + def save_config_to_db(self, conn): + """ Save the part of the configuration that cannot be changed into + the database. + """ + set_property(conn, DBCFG_IMPORT_NORM_RULES, self.normalization_rules) + set_property(conn, DBCFG_IMPORT_TRANS_RULES, self.transliteration_rules) + set_property(conn, DBCFG_IMPORT_ANALYSIS_RULES, json.dumps(self.analysis_rules)) - if configfile.suffix == '.yaml': - self._load_from_yaml() - else: - raise UsageError("Unknown format of tokenizer configuration.") + + def make_sanitizer(self): + """ Create a place sanitizer from the configured rules. + """ + return PlaceSanitizer(self.sanitizer_rules) + + + def make_token_analysis(self): + """ Create a token analyser from the reviouly loaded rules. + """ + return ICUTokenAnalysis(self.normalization_rules, + self.transliteration_rules, self.analysis) def get_search_rules(self): @@ -70,177 +101,66 @@ class ICURuleLoader: rules.write(self.transliteration_rules) return rules.getvalue() + def get_normalization_rules(self): """ Return rules for normalisation of a term. """ return self.normalization_rules + def get_transliteration_rules(self): """ Return the rules for converting a string into its asciii representation. """ return self.transliteration_rules - def get_replacement_pairs(self): - """ Return the list of possible compound decompositions with - application of abbreviations included. - The result is a list of pairs: the first item is the sequence to - replace, the second is a list of replacements. - """ - return self.variants - - def _yaml_include_representer(self, loader, node): - value = loader.construct_scalar(node) - - if Path(value).is_absolute(): - content = Path(value) - else: - content = (self.configfile.parent / value) - - return yaml.safe_load(content.read_text(encoding='utf-8')) - - - def _load_from_yaml(self): - yaml.add_constructor('!include', self._yaml_include_representer, - Loader=yaml.SafeLoader) - rules = yaml.safe_load(self.configfile.read_text(encoding='utf-8')) - - self.normalization_rules = self._cfg_to_icu_rules(rules, 'normalization') - self.transliteration_rules = self._cfg_to_icu_rules(rules, 'transliteration') - self._parse_variant_list(self._get_section(rules, 'variants')) - - def _get_section(self, rules, section): - """ Get the section named 'section' from the rules. If the section does - not exist, raise a usage error with a meaningful message. + def _setup_analysis(self): + """ Process the rules used for creating the various token analyzers. """ - if section not in rules: - LOG.fatal("Section '%s' not found in tokenizer config '%s'.", - section, str(self.configfile)) - raise UsageError("Syntax error in tokenizer configuration file.") + self.analysis = {} - return rules[section] + if not isinstance(self.analysis_rules, list): + raise UsageError("Configuration section 'token-analysis' must be a list.") + for section in self.analysis_rules: + name = section.get('id', None) + if name in self.analysis: + if name is None: + LOG.fatal("ICU tokenizer configuration has two default token analyzers.") + else: + LOG.fatal("ICU tokenizer configuration has two token " + "analyzers with id '%s'.", name) + raise UsageError("Syntax error in ICU tokenizer config.") + self.analysis[name] = TokenAnalyzerRule(section, self.normalization_rules) - def _cfg_to_icu_rules(self, rules, section): + + @staticmethod + def _cfg_to_icu_rules(rules, section): """ Load an ICU ruleset from the given section. If the section is a simple string, it is interpreted as a file name and the rules are loaded verbatim from the given file. The filename is expected to be relative to the tokenizer rule file. If the section is a list then each line is assumed to be a rule. All rules are concatenated and returned. """ - content = self._get_section(rules, section) + content = _get_section(rules, section) if content is None: return '' - return ';'.join(_flatten_yaml_list(content)) + ';' - - - def _parse_variant_list(self, rules): - self.variants.clear() - - if not rules: - return - - rules = _flatten_yaml_list(rules) - - vmaker = _VariantMaker(self.normalization_rules) + return ';'.join(flatten_config_list(content, section)) + ';' - properties = [] - for section in rules: - # Create the property field and deduplicate against existing - # instances. - props = variants.ICUVariantProperties.from_rules(section) - for existing in properties: - if existing == props: - props = existing - break - else: - properties.append(props) - for rule in (section.get('words') or []): - self.variants.update(vmaker.compute(rule, props)) - - -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. +class TokenAnalyzerRule: + """ Factory for a single analysis module. The class saves the configuration + and creates a new token analyzer on request. """ - def __init__(self, norm_rules): - self.norm = Transliterator.createFromRules("rule_loader_normalization", - norm_rules) + def __init__(self, rules, normalization_rules): + # Find the analysis module + module_name = 'nominatim.tokenizer.token_analysis.' \ + + _get_section(rules, 'analyzer').replace('-', '_') + analysis_mod = importlib.import_module(module_name) + self.create = analysis_mod.create - - def compute(self, rule, props): - """ 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 variants.ICUVariant(froms, tos, props) - - for src, repl in itertools.product(src_terms, repl_terms): - if src and repl: - for froms, tos in _create_variants(*src, repl, decompose): - yield variants.ICUVariant(froms, tos, props) - - - 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)) - 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 + # Load the configuration. + self.config = analysis_mod.configure(rules, normalization_rules)