mirror of
https://github.com/osm-search/Nominatim.git
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682 lines
26 KiB
Python
682 lines
26 KiB
Python
# SPDX-License-Identifier: GPL-2.0-only
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#
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# This file is part of Nominatim. (https://nominatim.org)
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#
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# Copyright (C) 2022 by the Nominatim developer community.
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# For a full list of authors see the git log.
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"""
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Tokenizer implementing normalisation as used before Nominatim 4.
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"""
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from typing import Optional, Sequence, List, Tuple, Mapping, Any, Callable, \
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cast, Dict, Set, Iterable
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from collections import OrderedDict
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import logging
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from pathlib import Path
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import re
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import shutil
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from textwrap import dedent
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from icu import Transliterator
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import psycopg2
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import psycopg2.extras
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from nominatim.db.connection import connect, Connection
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from nominatim.config import Configuration
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from nominatim.db import properties
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from nominatim.db import utils as db_utils
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from nominatim.db.sql_preprocessor import SQLPreprocessor
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from nominatim.data.place_info import PlaceInfo
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from nominatim.errors import UsageError
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from nominatim.tokenizer.base import AbstractAnalyzer, AbstractTokenizer
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DBCFG_NORMALIZATION = "tokenizer_normalization"
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DBCFG_MAXWORDFREQ = "tokenizer_maxwordfreq"
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LOG = logging.getLogger()
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def create(dsn: str, data_dir: Path) -> 'LegacyTokenizer':
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""" Create a new instance of the tokenizer provided by this module.
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"""
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return LegacyTokenizer(dsn, data_dir)
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def _install_module(config_module_path: str, src_dir: Path, module_dir: Path) -> str:
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""" Copies the PostgreSQL normalisation module into the project
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directory if necessary. For historical reasons the module is
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saved in the '/module' subdirectory and not with the other tokenizer
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data.
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The function detects when the installation is run from the
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build directory. It doesn't touch the module in that case.
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"""
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# Custom module locations are simply used as is.
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if config_module_path:
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LOG.info("Using custom path for database module at '%s'", config_module_path)
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return config_module_path
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# Compatibility mode for builddir installations.
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if module_dir.exists() and src_dir.samefile(module_dir):
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LOG.info('Running from build directory. Leaving database module as is.')
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return str(module_dir)
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# In any other case install the module in the project directory.
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if not module_dir.exists():
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module_dir.mkdir()
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destfile = module_dir / 'nominatim.so'
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shutil.copy(str(src_dir / 'nominatim.so'), str(destfile))
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destfile.chmod(0o755)
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LOG.info('Database module installed at %s', str(destfile))
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return str(module_dir)
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def _check_module(module_dir: str, conn: Connection) -> None:
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""" Try to use the PostgreSQL module to confirm that it is correctly
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installed and accessible from PostgreSQL.
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"""
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with conn.cursor() as cur:
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try:
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cur.execute("""CREATE FUNCTION nominatim_test_import_func(text)
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RETURNS text AS %s, 'transliteration'
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LANGUAGE c IMMUTABLE STRICT;
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DROP FUNCTION nominatim_test_import_func(text)
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""", (f'{module_dir}/nominatim.so', ))
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except psycopg2.DatabaseError as err:
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LOG.fatal("Error accessing database module: %s", err)
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raise UsageError("Database module cannot be accessed.") from err
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class LegacyTokenizer(AbstractTokenizer):
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""" The legacy tokenizer uses a special PostgreSQL module to normalize
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names and queries. The tokenizer thus implements normalization through
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calls to the database.
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"""
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def __init__(self, dsn: str, data_dir: Path) -> None:
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self.dsn = dsn
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self.data_dir = data_dir
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self.normalization: Optional[str] = None
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def init_new_db(self, config: Configuration, init_db: bool = True) -> None:
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""" Set up a new tokenizer for the database.
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This copies all necessary data in the project directory to make
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sure the tokenizer remains stable even over updates.
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"""
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assert config.project_dir is not None
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module_dir = _install_module(config.DATABASE_MODULE_PATH,
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config.lib_dir.module,
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config.project_dir / 'module')
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self.normalization = config.TERM_NORMALIZATION
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self._install_php(config, overwrite=True)
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with connect(self.dsn) as conn:
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_check_module(module_dir, conn)
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self._save_config(conn, config)
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conn.commit()
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if init_db:
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self.update_sql_functions(config)
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self._init_db_tables(config)
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def init_from_project(self, config: Configuration) -> None:
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""" Initialise the tokenizer from the project directory.
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"""
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assert config.project_dir is not None
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with connect(self.dsn) as conn:
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self.normalization = properties.get_property(conn, DBCFG_NORMALIZATION)
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if not (config.project_dir / 'module' / 'nominatim.so').exists():
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_install_module(config.DATABASE_MODULE_PATH,
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config.lib_dir.module,
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config.project_dir / 'module')
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self._install_php(config, overwrite=False)
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def finalize_import(self, config: Configuration) -> None:
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""" Do any required postprocessing to make the tokenizer data ready
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for use.
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"""
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with connect(self.dsn) as conn:
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sqlp = SQLPreprocessor(conn, config)
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sqlp.run_sql_file(conn, 'tokenizer/legacy_tokenizer_indices.sql')
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def update_sql_functions(self, config: Configuration) -> None:
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""" Reimport the SQL functions for this tokenizer.
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"""
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assert config.project_dir is not None
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with connect(self.dsn) as conn:
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max_word_freq = properties.get_property(conn, DBCFG_MAXWORDFREQ)
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modulepath = config.DATABASE_MODULE_PATH or \
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str((config.project_dir / 'module').resolve())
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sqlp = SQLPreprocessor(conn, config)
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sqlp.run_sql_file(conn, 'tokenizer/legacy_tokenizer.sql',
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max_word_freq=max_word_freq,
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modulepath=modulepath)
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def check_database(self, _: Configuration) -> Optional[str]:
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""" Check that the tokenizer is set up correctly.
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"""
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hint = """\
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The Postgresql extension nominatim.so was not correctly loaded.
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Error: {error}
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Hints:
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* Check the output of the CMmake/make installation step
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* Does nominatim.so exist?
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* Does nominatim.so exist on the database server?
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* Can nominatim.so be accessed by the database user?
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"""
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with connect(self.dsn) as conn:
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with conn.cursor() as cur:
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try:
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out = cur.scalar("SELECT make_standard_name('a')")
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except psycopg2.Error as err:
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return hint.format(error=str(err))
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if out != 'a':
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return hint.format(error='Unexpected result for make_standard_name()')
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return None
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def migrate_database(self, config: Configuration) -> None:
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""" Initialise the project directory of an existing database for
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use with this tokenizer.
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This is a special migration function for updating existing databases
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to new software versions.
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"""
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assert config.project_dir is not None
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self.normalization = config.TERM_NORMALIZATION
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module_dir = _install_module(config.DATABASE_MODULE_PATH,
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config.lib_dir.module,
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config.project_dir / 'module')
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with connect(self.dsn) as conn:
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_check_module(module_dir, conn)
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self._save_config(conn, config)
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def update_statistics(self, _: Configuration) -> None:
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""" Recompute the frequency of full words.
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"""
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with connect(self.dsn) as conn:
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if conn.table_exists('search_name'):
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with conn.cursor() as cur:
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cur.drop_table("word_frequencies")
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LOG.info("Computing word frequencies")
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cur.execute("""CREATE TEMP TABLE word_frequencies AS
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SELECT unnest(name_vector) as id, count(*)
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FROM search_name GROUP BY id""")
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cur.execute("CREATE INDEX ON word_frequencies(id)")
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LOG.info("Update word table with recomputed frequencies")
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cur.execute("""UPDATE word SET search_name_count = count
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FROM word_frequencies
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WHERE word_token like ' %' and word_id = id""")
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cur.drop_table("word_frequencies")
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conn.commit()
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def update_word_tokens(self) -> None:
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""" No house-keeping implemented for the legacy tokenizer.
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"""
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LOG.info("No tokenizer clean-up available.")
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def name_analyzer(self) -> 'LegacyNameAnalyzer':
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""" Create a new analyzer for tokenizing names and queries
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using this tokinzer. Analyzers are context managers and should
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be used accordingly:
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```
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with tokenizer.name_analyzer() as analyzer:
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analyser.tokenize()
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```
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When used outside the with construct, the caller must ensure to
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call the close() function before destructing the analyzer.
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Analyzers are not thread-safe. You need to instantiate one per thread.
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"""
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normalizer = Transliterator.createFromRules("phrase normalizer",
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self.normalization)
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return LegacyNameAnalyzer(self.dsn, normalizer)
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def most_frequent_words(self, conn: Connection, num: int) -> List[str]:
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""" Return a list of the `num` most frequent full words
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in the database.
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"""
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with conn.cursor() as cur:
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cur.execute(""" SELECT word FROM word WHERE word is not null
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ORDER BY search_name_count DESC LIMIT %s""", (num,))
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return list(s[0] for s in cur)
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def _install_php(self, config: Configuration, overwrite: bool = True) -> None:
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""" Install the php script for the tokenizer.
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"""
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if config.lib_dir.php is not None:
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php_file = self.data_dir / "tokenizer.php"
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if not php_file.exists() or overwrite:
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php_file.write_text(dedent(f"""\
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<?php
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@define('CONST_Max_Word_Frequency', {config.MAX_WORD_FREQUENCY});
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@define('CONST_Term_Normalization_Rules', "{config.TERM_NORMALIZATION}");
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require_once('{config.lib_dir.php}/tokenizer/legacy_tokenizer.php');
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"""), encoding='utf-8')
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def _init_db_tables(self, config: Configuration) -> None:
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""" Set up the word table and fill it with pre-computed word
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frequencies.
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"""
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with connect(self.dsn) as conn:
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sqlp = SQLPreprocessor(conn, config)
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sqlp.run_sql_file(conn, 'tokenizer/legacy_tokenizer_tables.sql')
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conn.commit()
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LOG.warning("Precomputing word tokens")
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db_utils.execute_file(self.dsn, config.lib_dir.data / 'words.sql')
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def _save_config(self, conn: Connection, config: Configuration) -> None:
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""" Save the configuration that needs to remain stable for the given
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database as database properties.
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"""
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assert self.normalization is not None
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properties.set_property(conn, DBCFG_NORMALIZATION, self.normalization)
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properties.set_property(conn, DBCFG_MAXWORDFREQ, config.MAX_WORD_FREQUENCY)
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class LegacyNameAnalyzer(AbstractAnalyzer):
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""" The legacy analyzer uses the special Postgresql module for
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splitting names.
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Each instance opens a connection to the database to request the
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normalization.
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"""
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def __init__(self, dsn: str, normalizer: Any):
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self.conn: Optional[Connection] = connect(dsn).connection
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self.conn.autocommit = True
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self.normalizer = normalizer
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psycopg2.extras.register_hstore(self.conn)
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self._cache = _TokenCache(self.conn)
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def close(self) -> None:
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""" Free all resources used by the analyzer.
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"""
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if self.conn:
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self.conn.close()
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self.conn = None
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def get_word_token_info(self, words: Sequence[str]) -> List[Tuple[str, str, int]]:
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""" Return token information for the given list of words.
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If a word starts with # it is assumed to be a full name
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otherwise is a partial name.
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The function returns a list of tuples with
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(original word, word token, word id).
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The function is used for testing and debugging only
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and not necessarily efficient.
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"""
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assert self.conn is not None
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with self.conn.cursor() as cur:
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cur.execute("""SELECT t.term, word_token, word_id
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FROM word, (SELECT unnest(%s::TEXT[]) as term) t
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WHERE word_token = (CASE
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WHEN left(t.term, 1) = '#' THEN
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' ' || make_standard_name(substring(t.term from 2))
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ELSE
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make_standard_name(t.term)
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END)
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and class is null and country_code is null""",
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(words, ))
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return [(r[0], r[1], r[2]) for r in cur]
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def normalize(self, phrase: str) -> str:
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""" Normalize the given phrase, i.e. remove all properties that
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are irrelevant for search.
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"""
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return cast(str, self.normalizer.transliterate(phrase))
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def normalize_postcode(self, postcode: str) -> str:
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""" Convert the postcode to a standardized form.
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This function must yield exactly the same result as the SQL function
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'token_normalized_postcode()'.
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"""
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return postcode.strip().upper()
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def update_postcodes_from_db(self) -> None:
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""" Update postcode tokens in the word table from the location_postcode
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table.
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"""
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assert self.conn is not None
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with self.conn.cursor() as cur:
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# This finds us the rows in location_postcode and word that are
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# missing in the other table.
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cur.execute("""SELECT * FROM
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(SELECT pc, word FROM
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(SELECT distinct(postcode) as pc FROM location_postcode) p
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FULL JOIN
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(SELECT word FROM word
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WHERE class ='place' and type = 'postcode') w
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ON pc = word) x
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WHERE pc is null or word is null""")
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to_delete = []
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to_add = []
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for postcode, word in cur:
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if postcode is None:
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to_delete.append(word)
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else:
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to_add.append(postcode)
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if to_delete:
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cur.execute("""DELETE FROM WORD
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WHERE class ='place' and type = 'postcode'
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and word = any(%s)
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""", (to_delete, ))
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if to_add:
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cur.execute("""SELECT count(create_postcode_id(pc))
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FROM unnest(%s) as pc
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""", (to_add, ))
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def update_special_phrases(self, phrases: Iterable[Tuple[str, str, str, str]],
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should_replace: bool) -> None:
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""" Replace the search index for special phrases with the new phrases.
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"""
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assert self.conn is not None
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norm_phrases = set(((self.normalize(p[0]), p[1], p[2], p[3])
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for p in phrases))
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with self.conn.cursor() as cur:
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# Get the old phrases.
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existing_phrases = set()
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cur.execute("""SELECT word, class, type, operator FROM word
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WHERE class != 'place'
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OR (type != 'house' AND type != 'postcode')""")
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for label, cls, typ, oper in cur:
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existing_phrases.add((label, cls, typ, oper or '-'))
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to_add = norm_phrases - existing_phrases
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to_delete = existing_phrases - norm_phrases
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if to_add:
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cur.execute_values(
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""" INSERT INTO word (word_id, word_token, word, class, type,
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search_name_count, operator)
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(SELECT nextval('seq_word'), ' ' || make_standard_name(name), name,
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class, type, 0,
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CASE WHEN op in ('in', 'near') THEN op ELSE null END
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FROM (VALUES %s) as v(name, class, type, op))""",
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to_add)
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if to_delete and should_replace:
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cur.execute_values(
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""" DELETE FROM word USING (VALUES %s) as v(name, in_class, in_type, op)
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WHERE word = name and class = in_class and type = in_type
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and ((op = '-' and operator is null) or op = operator)""",
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to_delete)
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LOG.info("Total phrases: %s. Added: %s. Deleted: %s",
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len(norm_phrases), len(to_add), len(to_delete))
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def add_country_names(self, country_code: str, names: Mapping[str, str]) -> None:
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""" Add names for the given country to the search index.
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"""
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assert self.conn is not None
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with self.conn.cursor() as cur:
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cur.execute(
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"""INSERT INTO word (word_id, word_token, country_code)
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(SELECT nextval('seq_word'), lookup_token, %s
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FROM (SELECT DISTINCT ' ' || make_standard_name(n) as lookup_token
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FROM unnest(%s)n) y
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WHERE NOT EXISTS(SELECT * FROM word
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WHERE word_token = lookup_token and country_code = %s))
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""", (country_code, list(names.values()), country_code))
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def process_place(self, place: PlaceInfo) -> Mapping[str, Any]:
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""" Determine tokenizer information about the given place.
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Returns a JSON-serialisable structure that will be handed into
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the database via the token_info field.
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"""
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assert self.conn is not None
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token_info = _TokenInfo(self._cache)
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names = place.name
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if names:
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token_info.add_names(self.conn, names)
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if place.is_country():
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assert place.country_code is not None
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self.add_country_names(place.country_code, names)
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address = place.address
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if address:
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self._process_place_address(token_info, address)
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return token_info.data
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def _process_place_address(self, token_info: '_TokenInfo', address: Mapping[str, str]) -> None:
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assert self.conn is not None
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hnrs = []
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addr_terms = []
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for key, value in address.items():
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if key == 'postcode':
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# Make sure the normalized postcode is present in the word table.
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if re.search(r'[:,;]', value) is None:
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norm_pc = self.normalize_postcode(value)
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token_info.set_postcode(norm_pc)
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self._cache.add_postcode(self.conn, norm_pc)
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elif key in ('housenumber', 'streetnumber', 'conscriptionnumber'):
|
|
hnrs.append(value)
|
|
elif key == 'street':
|
|
token_info.add_street(self.conn, value)
|
|
elif key == 'place':
|
|
token_info.add_place(self.conn, value)
|
|
elif not key.startswith('_') \
|
|
and key not in ('country', 'full', 'inclusion'):
|
|
addr_terms.append((key, value))
|
|
|
|
if hnrs:
|
|
token_info.add_housenumbers(self.conn, hnrs)
|
|
|
|
if addr_terms:
|
|
token_info.add_address_terms(self.conn, addr_terms)
|
|
|
|
|
|
|
|
class _TokenInfo:
|
|
""" Collect token information to be sent back to the database.
|
|
"""
|
|
def __init__(self, cache: '_TokenCache') -> None:
|
|
self.cache = cache
|
|
self.data: Dict[str, Any] = {}
|
|
|
|
|
|
def add_names(self, conn: Connection, names: Mapping[str, str]) -> None:
|
|
""" Add token information for the names of the place.
|
|
"""
|
|
with conn.cursor() as cur:
|
|
# Create the token IDs for all names.
|
|
self.data['names'] = cur.scalar("SELECT make_keywords(%s)::text",
|
|
(names, ))
|
|
|
|
|
|
def add_housenumbers(self, conn: Connection, hnrs: Sequence[str]) -> None:
|
|
""" Extract housenumber information from the address.
|
|
"""
|
|
if len(hnrs) == 1:
|
|
token = self.cache.get_housenumber(hnrs[0])
|
|
if token is not None:
|
|
self.data['hnr_tokens'] = token
|
|
self.data['hnr'] = hnrs[0]
|
|
return
|
|
|
|
# split numbers if necessary
|
|
simple_list: List[str] = []
|
|
for hnr in hnrs:
|
|
simple_list.extend((x.strip() for x in re.split(r'[;,]', hnr)))
|
|
|
|
if len(simple_list) > 1:
|
|
simple_list = list(set(simple_list))
|
|
|
|
with conn.cursor() as cur:
|
|
cur.execute("SELECT * FROM create_housenumbers(%s)", (simple_list, ))
|
|
result = cur.fetchone()
|
|
assert result is not None
|
|
self.data['hnr_tokens'], self.data['hnr'] = result
|
|
|
|
|
|
def set_postcode(self, postcode: str) -> None:
|
|
""" Set or replace the postcode token with the given value.
|
|
"""
|
|
self.data['postcode'] = postcode
|
|
|
|
def add_street(self, conn: Connection, street: str) -> None:
|
|
""" Add addr:street match terms.
|
|
"""
|
|
def _get_street(name: str) -> Optional[str]:
|
|
with conn.cursor() as cur:
|
|
return cast(Optional[str],
|
|
cur.scalar("SELECT word_ids_from_name(%s)::text", (name, )))
|
|
|
|
tokens = self.cache.streets.get(street, _get_street)
|
|
self.data['street'] = tokens or '{}'
|
|
|
|
|
|
def add_place(self, conn: Connection, place: str) -> None:
|
|
""" Add addr:place search and match terms.
|
|
"""
|
|
def _get_place(name: str) -> Tuple[List[int], List[int]]:
|
|
with conn.cursor() as cur:
|
|
cur.execute("""SELECT make_keywords(hstore('name' , %s))::text,
|
|
word_ids_from_name(%s)::text""",
|
|
(name, name))
|
|
return cast(Tuple[List[int], List[int]], cur.fetchone())
|
|
|
|
self.data['place_search'], self.data['place_match'] = \
|
|
self.cache.places.get(place, _get_place)
|
|
|
|
|
|
def add_address_terms(self, conn: Connection, terms: Sequence[Tuple[str, str]]) -> None:
|
|
""" Add additional address terms.
|
|
"""
|
|
def _get_address_term(name: str) -> Tuple[List[int], List[int]]:
|
|
with conn.cursor() as cur:
|
|
cur.execute("""SELECT addr_ids_from_name(%s)::text,
|
|
word_ids_from_name(%s)::text""",
|
|
(name, name))
|
|
return cast(Tuple[List[int], List[int]], cur.fetchone())
|
|
|
|
tokens = {}
|
|
for key, value in terms:
|
|
items = self.cache.address_terms.get(value, _get_address_term)
|
|
if items[0] or items[1]:
|
|
tokens[key] = items
|
|
|
|
if tokens:
|
|
self.data['addr'] = tokens
|
|
|
|
|
|
class _LRU:
|
|
""" Least recently used cache that accepts a generator function to
|
|
produce the item when there is a cache miss.
|
|
"""
|
|
|
|
def __init__(self, maxsize: int = 128):
|
|
self.data: 'OrderedDict[str, Any]' = OrderedDict()
|
|
self.maxsize = maxsize
|
|
|
|
|
|
def get(self, key: str, generator: Callable[[str], Any]) -> Any:
|
|
""" Get the item with the given key from the cache. If nothing
|
|
is found in the cache, generate the value through the
|
|
generator function and store it in the cache.
|
|
"""
|
|
value = self.data.get(key)
|
|
if value is not None:
|
|
self.data.move_to_end(key)
|
|
else:
|
|
value = generator(key)
|
|
if len(self.data) >= self.maxsize:
|
|
self.data.popitem(last=False)
|
|
self.data[key] = value
|
|
|
|
return value
|
|
|
|
|
|
class _TokenCache:
|
|
""" Cache for token information to avoid repeated database queries.
|
|
|
|
This cache is not thread-safe and needs to be instantiated per
|
|
analyzer.
|
|
"""
|
|
def __init__(self, conn: Connection):
|
|
# various LRU caches
|
|
self.streets = _LRU(maxsize=256)
|
|
self.places = _LRU(maxsize=128)
|
|
self.address_terms = _LRU(maxsize=1024)
|
|
|
|
# Lookup houseunumbers up to 100 and cache them
|
|
with conn.cursor() as cur:
|
|
cur.execute("""SELECT i, ARRAY[getorcreate_housenumber_id(i::text)]::text
|
|
FROM generate_series(1, 100) as i""")
|
|
self._cached_housenumbers: Dict[str, str] = {str(r[0]): r[1] for r in cur}
|
|
|
|
# For postcodes remember the ones that have already been added
|
|
self.postcodes: Set[str] = set()
|
|
|
|
def get_housenumber(self, number: str) -> Optional[str]:
|
|
""" Get a housenumber token from the cache.
|
|
"""
|
|
return self._cached_housenumbers.get(number)
|
|
|
|
|
|
def add_postcode(self, conn: Connection, postcode: str) -> None:
|
|
""" Make sure the given postcode is in the database.
|
|
"""
|
|
if postcode not in self.postcodes:
|
|
with conn.cursor() as cur:
|
|
cur.execute('SELECT create_postcode_id(%s)', (postcode, ))
|
|
self.postcodes.add(postcode)
|