Merge remote-tracking branch 'upstream/master'

[nominatim.git] / nominatim / tokenizer / token_analysis / generic.py

diff --git a/nominatim/tokenizer/token_analysis/generic.py b/nominatim/tokenizer/token_analysis/generic.py
index f0de0cca4e28c5f8e2601086153704bc8637f269..f790dad27a24d9f11300ab1f6d78c147b829797b 100644 (file)
--- a/nominatim/tokenizer/token_analysis/generic.py
+++ b/nominatim/tokenizer/token_analysis/generic.py
@@ -1,7 +1,13 @@
+# 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.

 """
 Generic processor for names that creates abbreviation variants.
 """
 """
 Generic processor for names that creates abbreviation variants.
 """

-from collections import defaultdict
+from collections import defaultdict, namedtuple

 import itertools
 import re
 
 import itertools
 import re
 


@@ -10,41 +16,50 @@ import datrie
 
 from nominatim.config import flatten_config_list
 from nominatim.errors import UsageError
 
 from nominatim.config import flatten_config_list
 from nominatim.errors import UsageError

-import nominatim.tokenizer.icu_variants as variants

 
 ### Configuration section
 
 
 ### Configuration section
 

+ICUVariant = namedtuple('ICUVariant', ['source', 'replacement'])
+

 def configure(rules, normalization_rules):
     """ Extract and preprocess the configuration for this module.
     """
 def configure(rules, normalization_rules):
     """ Extract and preprocess the configuration for this module.
     """

-    return {'variants': _parse_variant_list(rules.get('variants'),
-                                            normalization_rules)}
+    config = {}
+
+    config['replacements'], config['chars'] = _get_variant_config(rules.get('variants'),
+                                                                  normalization_rules)
+    config['variant_only'] = rules.get('mode', '') == 'variant-only'

 
 

+    return config

 
 

-def _parse_variant_list(rules, normalization_rules):
-    vset = set()
+
+def _get_variant_config(rules, normalization_rules):
+    """ Convert the variant definition from the configuration into
+        replacement sets.
+    """
+    immediate = defaultdict(list)
+    chars = set()

 
     if rules:
 
     if rules:

+        vset = set()

         rules = flatten_config_list(rules, 'variants')
 
         vmaker = _VariantMaker(normalization_rules)
 
         rules = flatten_config_list(rules, 'variants')
 
         vmaker = _VariantMaker(normalization_rules)
 

-        properties = []

         for section in rules:
         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 []):
             for rule in (section.get('words') or []):

-                vset.update(vmaker.compute(rule, props))
+                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 vset
+    return list(immediate.items()), ''.join(chars)

 
 
 class _VariantMaker:
 
 
 class _VariantMaker:


@@ -58,7 +73,7 @@ class _VariantMaker:
                                                    norm_rules)
 
 
                                                    norm_rules)
 
 

-    def compute(self, rule, props):
+    def compute(self, rule):

         """ Generator for all ICUVariant tuples from a single variant rule.
         """
         parts = re.split(r'(\|)?([=-])>', rule)
         """ Generator for all ICUVariant tuples from a single variant rule.
         """
         parts = re.split(r'(\|)?([=-])>', rule)


@@ -67,19 +82,19 @@ class _VariantMaker:
 
         decompose = parts[1] is None
         src_terms = [self._parse_variant_word(t) for t in parts[0].split(',')]
 
         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(','))
+        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):
 
         # 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)
+                        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):
 
         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)
+                    yield ICUVariant(froms, tos)

 
 
     def _parse_variant_word(self, name):
 
 
     def _parse_variant_word(self, name):


@@ -87,7 +102,7 @@ class _VariantMaker:
         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))
         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))
+        norm_name = self.norm.transliterate(match.group(2)).strip()

         if not norm_name:
             return None
 
         if not norm_name:
             return None
 


@@ -133,10 +148,10 @@ def _create_variants(src, preflag, postflag, repl, decompose):
 
 ### Analysis section
 
 
 ### Analysis section
 

-def create(norm_rules, trans_rules, config):
+def create(transliterator, config):

     """ Create a new token analysis instance for this module.
     """
     """ Create a new token analysis instance for this module.
     """

-    return GenericTokenAnalysis(norm_rules, trans_rules, config['variants'])
+    return GenericTokenAnalysis(transliterator, config)

 
 
 class GenericTokenAnalysis:
 
 
 class GenericTokenAnalysis:


@@ -144,37 +159,19 @@ class GenericTokenAnalysis:
         and provides the functions to apply the transformations.
     """
 
         and provides the functions to apply the transformations.
     """
 

-    def __init__(self, norm_rules, trans_rules, replacements):
-        self.normalizer = Transliterator.createFromRules("icu_normalization",
-                                                         norm_rules)
-        self.to_ascii = Transliterator.createFromRules("icu_to_ascii",
-                                                       trans_rules +
-                                                       ";[:Space:]+ > ' '")
-        self.search = Transliterator.createFromRules("icu_search",
-                                                     norm_rules + trans_rules)
+    def __init__(self, to_ascii, config):
+        self.to_ascii = to_ascii
+        self.variant_only = config['variant_only']

 
 

-        # Intermediate reorder by source. Also compute required character set.
-        immediate = defaultdict(list)
-        chars = set()
-        for variant in replacements:
-            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)
-        # Then copy to datrie
-        self.replacements = datrie.Trie(''.join(chars))
-        for src, repllist in immediate.items():
-            self.replacements[src] = repllist
+        # Set up datrie
+        if config['replacements']:
+            self.replacements = datrie.Trie(config['chars'])
+            for src, repllist in config['replacements']:
+                self.replacements[src] = repllist
+        else:
+            self.replacements = None

 
 
 
 

-    def get_normalized(self, name):
-        """ Normalize the given name, i.e. remove all elements not relevant
-            for search.
-        """
-        return self.normalizer.transliterate(name).strip()
-

     def get_variants_ascii(self, norm_name):
         """ Compute the spelling variants for the given normalized name
             and transliterate the result.
     def get_variants_ascii(self, norm_name):
         """ Compute the spelling variants for the given normalized name
             and transliterate the result.


@@ -183,52 +180,51 @@ class GenericTokenAnalysis:
         partials = ['']
 
         startpos = 0
         partials = ['']
 
         startpos = 0

-        pos = 0
-        force_space = False
-        while pos < len(baseform):
-            full, repl = self.replacements.longest_prefix_item(baseform[pos:],
-                                                               (None, None))
-            if full is not None:
-                done = baseform[startpos:pos]
-                partials = [v + done + r
-                            for v, r in itertools.product(partials, repl)
-                            if not force_space or r.startswith(' ')]
-                if len(partials) > 128:
-                    # If too many variants are produced, they are unlikely
-                    # to be helpful. Only use the original term.
-                    startpos = 0
-                    break
-                startpos = pos + len(full)
-                if full[-1] == ' ':
-                    startpos -= 1
-                    force_space = True
-                pos = startpos
-            else:
-                pos += 1
-                force_space = False
+        if self.replacements is not None:
+            pos = 0
+            force_space = False
+            while pos < len(baseform):
+                full, repl = self.replacements.longest_prefix_item(baseform[pos:],
+                                                                   (None, None))
+                if full is not None:
+                    done = baseform[startpos:pos]
+                    partials = [v + done + r
+                                for v, r in itertools.product(partials, repl)
+                                if not force_space or r.startswith(' ')]
+                    if len(partials) > 128:
+                        # If too many variants are produced, they are unlikely
+                        # to be helpful. Only use the original term.
+                        startpos = 0
+                        break
+                    startpos = pos + len(full)
+                    if full[-1] == ' ':
+                        startpos -= 1
+                        force_space = True
+                    pos = startpos
+                else:
+                    pos += 1
+                    force_space = False

 
         # No variants detected? Fast return.
         if startpos == 0:
 
         # No variants detected? Fast return.
         if startpos == 0:

+            if self.variant_only:
+                return []
+

             trans_name = self.to_ascii.transliterate(norm_name).strip()
             return [trans_name] if trans_name else []
 
             trans_name = self.to_ascii.transliterate(norm_name).strip()
             return [trans_name] if trans_name else []
 

-        return self._compute_result_set(partials, baseform[startpos:])
+        return self._compute_result_set(partials, baseform[startpos:],
+                                        norm_name if self.variant_only else '')

 
 
 
 

-    def _compute_result_set(self, partials, prefix):
+    def _compute_result_set(self, partials, prefix, exclude):

         results = set()
 
         for variant in partials:
         results = set()
 
         for variant in partials:

-            vname = variant + prefix
-            trans_name = self.to_ascii.transliterate(vname[1:-1]).strip()
-            if trans_name:
-                results.add(trans_name)
+            vname = (variant + prefix)[1:-1].strip()
+            if vname != exclude:
+                trans_name = self.to_ascii.transliterate(vname).strip()
+                if trans_name:
+                    results.add(trans_name)

 
         return list(results)
 
         return list(results)

-
-
-    def get_search_normalized(self, name):
-        """ Return the normalized version of the name (including transliteration)
-            to be applied at search time.
-        """
-        return self.search.transliterate(' ' + name + ' ').strip()