# Copyright (C) 2022 by the Nominatim developer community.
# For a full list of authors see the git log.
"""
-Abstract class defintions for tokenizers. These base classes are here
+Abstract class definitions for tokenizers. These base classes are here
mainly for documentation purposes.
"""
from abc import ABC, abstractmethod
-from typing import List, Tuple, Dict, Any
+from typing import List, Tuple, Dict, Any, Optional, Iterable
+from pathlib import Path
from nominatim.config import Configuration
+from nominatim.db.connection import Connection
from nominatim.data.place_info import PlaceInfo
-
-# pylint: disable=unnecessary-pass
+from nominatim.typing import Protocol
class AbstractAnalyzer(ABC):
""" The analyzer provides the functions for analysing names and building
@abstractmethod
- def update_special_phrases(self, phrases: List[Tuple[str, str, str, str]],
+ def update_special_phrases(self,
+ phrases: Iterable[Tuple[str, str, str, str]],
should_replace: bool) -> None:
""" Update the tokenizer's special phrase tokens from the given
list of special phrases.
the search index.
Arguments:
- place: Place information retrived from the database.
+ place: Place information retrieved from the database.
Returns:
A JSON-serialisable structure that will be handed into
init_db: When set to False, then initialisation of database
tables should be skipped. This option is only required for
- migration purposes and can be savely ignored by custom
+ migration purposes and can be safely ignored by custom
tokenizers.
TODO: can we move the init_db parameter somewhere else?
@abstractmethod
- def check_database(self, config: Configuration) -> str:
+ def check_database(self, config: Configuration) -> Optional[str]:
""" Check that the database is set up correctly and ready for being
queried.
When used outside the with construct, the caller must ensure to
call the close() function before destructing the analyzer.
"""
+
+
+ @abstractmethod
+ def most_frequent_words(self, conn: Connection, num: int) -> List[str]:
+ """ Return a list of the `num` most frequent full words
+ in the database.
+ """
+
+
+class TokenizerModule(Protocol):
+ """ Interface that must be exported by modules that implement their
+ own tokenizer.
+ """
+
+ def create(self, dsn: str, data_dir: Path) -> AbstractTokenizer:
+ """ Factory for new tokenizers.
+ """