]> git.openstreetmap.org Git - nominatim.git/blobdiff - nominatim/tokenizer/icu_rule_loader.py
filter duplicate results after DB query
[nominatim.git] / nominatim / tokenizer / icu_rule_loader.py
index 330179bb32630367448d38548f70e5e5b5b98934..4c36282ca54bfbd3526d24ead471a3e9fe9dbc33 100644 (file)
@@ -1,19 +1,27 @@
+# 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.
 """
+from typing import Mapping, Any, Dict, Optional
 import io
 import json
 import logging
-import itertools
-import re
 
 from icu import Transliterator
 
+from nominatim.config import flatten_config_list, Configuration
 from nominatim.db.properties import set_property, get_property
+from nominatim.db.connection import Connection
 from nominatim.errors import UsageError
-from nominatim.tokenizer.icu_name_processor import ICUNameProcessor
 from nominatim.tokenizer.place_sanitizer import PlaceSanitizer
-import nominatim.tokenizer.icu_variants as variants
+from nominatim.tokenizer.icu_token_analysis import ICUTokenAnalysis
+from nominatim.tokenizer.token_analysis.base import AnalysisModule, Analyzer
+import nominatim.data.country_info
 
 LOG = logging.getLogger()
 
@@ -22,65 +30,59 @@ DBCFG_IMPORT_TRANS_RULES = "tokenizer_import_transliteration"
 DBCFG_IMPORT_ANALYSIS_RULES = "tokenizer_import_analysis_rules"
 
 
-def _flatten_config_list(content):
-    if not content:
-        return []
-
-    if not isinstance(content, list):
-        raise UsageError("List expected in ICU configuration.")
-
-    output = []
-    for ele in content:
-        if isinstance(ele, list):
-            output.extend(_flatten_config_list(ele))
-        else:
-            output.append(ele)
-
-    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: Mapping[str, Any], section: str) -> Any:
+    """ 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, config):
+    def __init__(self, config: Configuration) -> None:
+        self.config = config
         rules = config.load_sub_configuration('icu_tokenizer.yaml',
                                               config='TOKENIZER_CONFIG')
 
-        self.variants = set()
+        # 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 = self._get_section(rules, 'variants')
-        self._parse_variant_list()
+        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):
+    def load_config_from_db(self, conn: Connection) -> None:
         """ 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._parse_variant_list()
+        rules = get_property(conn, DBCFG_IMPORT_NORM_RULES)
+        if rules is not None:
+            self.normalization_rules = rules
 
+        rules = get_property(conn, DBCFG_IMPORT_TRANS_RULES)
+        if rules is not None:
+            self.transliteration_rules = rules
 
-    def save_config_to_db(self, conn):
+        rules = get_property(conn, DBCFG_IMPORT_ANALYSIS_RULES)
+        if rules:
+            self.analysis_rules = json.loads(rules)
+        else:
+            self.analysis_rules = []
+        self._setup_analysis()
+
+
+    def save_config_to_db(self, conn: Connection) -> None:
         """ Save the part of the configuration that cannot be changed into
             the database.
         """
@@ -89,21 +91,20 @@ class ICURuleLoader:
         set_property(conn, DBCFG_IMPORT_ANALYSIS_RULES, json.dumps(self.analysis_rules))
 
 
-    def make_sanitizer(self):
+    def make_sanitizer(self) -> PlaceSanitizer:
         """ Create a place sanitizer from the configured rules.
         """
-        return PlaceSanitizer(self.sanitizer_rules)
+        return PlaceSanitizer(self.sanitizer_rules, self.config)
 
 
-    def make_token_analysis(self):
+    def make_token_analysis(self) -> ICUTokenAnalysis:
         """ Create a token analyser from the reviouly loaded rules.
         """
-        return ICUNameProcessor(self.normalization_rules,
-                                self.transliteration_rules,
-                                self.variants)
+        return ICUTokenAnalysis(self.normalization_rules,
+                                self.transliteration_rules, self.analysis)
 
 
-    def get_search_rules(self):
+    def get_search_rules(self) -> str:
         """ Return the ICU rules to be used during search.
             The rules combine normalization and transliteration.
         """
@@ -115,159 +116,81 @@ class ICURuleLoader:
         rules.write(self.transliteration_rules)
         return rules.getvalue()
 
-    def get_normalization_rules(self):
+
+    def get_normalization_rules(self) -> str:
         """ Return rules for normalisation of a term.
         """
         return self.normalization_rules
 
-    def get_transliteration_rules(self):
+
+    def get_transliteration_rules(self) -> str:
         """ 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.
+
+    def _setup_analysis(self) -> None:
+        """ Process the rules used for creating the various token analyzers.
         """
-        return self.variants
+        self.analysis: Dict[Optional[str], TokenAnalyzerRule]  = {}
 
+        if not isinstance(self.analysis_rules, list):
+            raise UsageError("Configuration section 'token-analysis' must be a list.")
 
-    @staticmethod
-    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.")
+        norm = Transliterator.createFromRules("rule_loader_normalization",
+                                              self.normalization_rules)
+        trans = Transliterator.createFromRules("rule_loader_transliteration",
+                                              self.transliteration_rules)
 
-        return rules[section]
+        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, norm, trans,
+                                                    self.config)
 
 
-    def _cfg_to_icu_rules(self, rules, section):
+    @staticmethod
+    def _cfg_to_icu_rules(rules: Mapping[str, Any], section: str) -> str:
         """ 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_config_list(content)) + ';'
-
-
-    def _parse_variant_list(self):
-        rules = self.analysis_rules
-
-        self.variants.clear()
+        return ';'.join(flatten_config_list(content, section)) + ';'
 
-        if not rules:
-            return
-
-        rules = _flatten_config_list(rules)
-
-        vmaker = _VariantMaker(self.normalization_rules)
-
-        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 TokenAnalyzerRule:
+    """ Factory for a single analysis module. The class saves the configuration
+        and creates a new token analyzer on request.
+    """
 
-class _VariantMaker:
-    """ Generater for all necessary ICUVariants from a single variant rule.
+    def __init__(self, rules: Mapping[str, Any],
+                 normalizer: Any, transliterator: Any,
+                 config: Configuration) -> None:
+        analyzer_name = _get_section(rules, 'analyzer')
+        if not analyzer_name or not isinstance(analyzer_name, str):
+            raise UsageError("'analyzer' parameter needs to be simple string")
 
-        All text in rules is normalized to make sure the variants match later.
-    """
+        self._analysis_mod: AnalysisModule = \
+            config.load_plugin_module(analyzer_name, 'nominatim.tokenizer.token_analysis')
 
-    def __init__(self, norm_rules):
-        self.norm = Transliterator.createFromRules("rule_loader_normalization",
-                                                   norm_rules)
+        self.config = self._analysis_mod.configure(rules, normalizer,
+                                                   transliterator)
 
 
-    def compute(self, rule, props):
-        """ Generator for all ICUVariant tuples from a single variant rule.
+    def create(self, normalizer: Any, transliterator: Any) -> Analyzer:
+        """ Create a new analyser instance for the given 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
+        return self._analysis_mod.create(normalizer, transliterator, self.config)