Source code for

import sqlite3
import warnings
from dataclasses import dataclass, field
from tempfile import NamedTemporaryFile
from typing import (

from .helper import initialize_table
from ..base.backend import BaseBackendMixin
from ....helper import random_identity, dataclass_from_dict

    from ....typing import DocumentArraySourceType

def _sanitize_table_name(table_name: str) -> str:
    ret = ''.join(c for c in table_name if c.isalnum() or c == '_')
    if ret != table_name:
        warnings.warn(f'The table name is changed to {ret} due to illegal characters')
    return ret

[docs]@dataclass class SqliteConfig: connection: Optional[Union[str, 'sqlite3.Connection']] = None table_name: Optional[str] = None serialize_config: Dict = field(default_factory=dict) conn_config: Dict = field(default_factory=dict) journal_mode: str = 'DELETE' synchronous: str = 'OFF'
[docs]class BackendMixin(BaseBackendMixin): """Provide necessary functions to enable this storage backend.""" schema_version = '0' def _sql(self, *args, **kwargs) -> 'sqlite3.Cursor': return self._cursor.execute(*args, **kwargs) def _commit(self): self._connection.commit() @property def _cursor(self) -> 'sqlite3.Cursor': return self._connection.cursor() def _init_storage( self, _docs: Optional['DocumentArraySourceType'] = None, config: Optional[Union[SqliteConfig, Dict]] = None, **kwargs, ): if not config: config = SqliteConfig() if isinstance(config, dict): config = dataclass_from_dict(SqliteConfig, config) from docarray import Document sqlite3.register_adapter( Document, lambda d: d.to_bytes(**config.serialize_config) ) sqlite3.register_converter( 'Document', lambda x: Document.from_bytes(x, **config.serialize_config) ) _conn_kwargs = dict() _conn_kwargs.update(config.conn_config) if config.connection is None: config.connection = NamedTemporaryFile().name if isinstance(config.connection, str): self._connection = sqlite3.connect( config.connection, detect_types=sqlite3.PARSE_DECLTYPES, check_same_thread=False, **_conn_kwargs, ) elif isinstance(config.connection, sqlite3.Connection): self._connection = config.connection else: raise TypeError( f'connection argument must be None or a string or a sqlite3.Connection, not `{type(config.connection)}`' ) self._connection.execute(f'PRAGMA synchronous={config.synchronous}') self._connection.execute(f'PRAGMA journal_mode={config.journal_mode}') self._table_name = ( _sanitize_table_name(self.__class__.__name__ + random_identity()) if config.table_name is None else _sanitize_table_name(config.table_name) ) self._persist = bool(config.table_name) config.table_name = self._table_name initialize_table( self._table_name, self.__class__.__name__, self.schema_version, self._cursor ) self._connection.commit() self._config = config super()._init_storage() if _docs is None: return elif isinstance(_docs, Iterable): self.clear() self.extend(_docs) else: self.clear() if isinstance(_docs, Document): self.append(_docs) def __getstate__(self): d = dict(self.__dict__) del d['_connection'] return d def __setstate__(self, state): self.__dict__ = state _conn_kwargs = dict() _conn_kwargs.update(state['_config'].conn_config) self._connection = sqlite3.connect( state['_config'].connection, detect_types=sqlite3.PARSE_DECLTYPES, check_same_thread=False, **_conn_kwargs, )