__package__ = 'archivebox.plugins_search.sqlite'
import sys
import codecs
import sqlite3
from typing import List, Iterable, Callable
from django.core.exceptions import ImproperlyConfigured
# Depends on other PyPI/vendor packages:
from pydantic import InstanceOf, Field, model_validator
# Depends on other Django apps:
from abx.archivebox.base_plugin import BasePlugin
from abx.archivebox.base_configset import BaseConfigSet
from abx.archivebox.base_hook import BaseHook
from abx.archivebox.base_searchbackend import BaseSearchBackend
# Depends on Other Plugins:
from archivebox.config.common import SEARCH_BACKEND_CONFIG
###################### Config ##########################
class SqliteftsConfig(BaseConfigSet):
SQLITEFTS_SEPARATE_DATABASE: bool = Field(default=True, alias='FTS_SEPARATE_DATABASE')
SQLITEFTS_TOKENIZERS: str = Field(default='porter unicode61 remove_diacritics 2', alias='FTS_TOKENIZERS')
SQLITEFTS_MAX_LENGTH: int = Field(default=int(1e9), alias='FTS_SQLITE_MAX_LENGTH')
# Not really meant to be user-modified, just here as constants
SQLITEFTS_DB: str = Field(default='search.sqlite3')
SQLITEFTS_TABLE: str = Field(default='snapshot_fts')
SQLITEFTS_ID_TABLE: str = Field(default='snapshot_id_fts')
SQLITEFTS_COLUMN: str = Field(default='texts')
@model_validator(mode='after')
def validate_fts_separate_database(self):
if SEARCH_BACKEND_CONFIG.SEARCH_BACKEND_ENGINE == 'sqlite' and self.SQLITEFTS_SEPARATE_DATABASE and not self.SQLITEFTS_DB:
sys.stderr.write('[X] Error: SQLITEFTS_DB must be set if SQLITEFTS_SEPARATE_DATABASE is True\n')
SEARCH_BACKEND_CONFIG.update_in_place(SEARCH_BACKEND_ENGINE='ripgrep')
return self
@property
def get_connection(self) -> Callable[[], sqlite3.Connection]:
# Make get_connection callable, because `django.db.connection.cursor()`
# has to be called to get a context manager, but sqlite3.Connection
# is a context manager without being called.
if self.SQLITEFTS_SEPARATE_DATABASE:
return lambda: sqlite3.connect(self.SQLITEFTS_DB)
else:
from django.db import connection as database
return database.cursor
@property
def SQLITE_BIND(self) -> str:
if self.SQLITEFTS_SEPARATE_DATABASE:
return "?"
else:
return "%s"
@property
def SQLITE_LIMIT_LENGTH(self) -> int:
from django.db import connection as database
# Only Python >= 3.11 supports sqlite3.Connection.getlimit(),
# so fall back to the default if the API to get the real value isn't present
try:
limit_id = sqlite3.SQLITE_LIMIT_LENGTH
if self.SQLITEFTS_SEPARATE_DATABASE:
cursor = self.get_connection()
return cursor.connection.getlimit(limit_id)
else:
with database.temporary_connection() as cursor: # type: ignore[attr-defined]
return cursor.connection.getlimit(limit_id)
except (AttributeError, ImproperlyConfigured):
return self.SQLITEFTS_MAX_LENGTH
SQLITEFTS_CONFIG = SqliteftsConfig()
def _escape_sqlite3(value: str, *, quote: str, errors='strict') -> str:
assert isinstance(quote, str), "quote is not a str"
assert len(quote) == 1, "quote must be a single character"
encodable = value.encode('utf-8', errors).decode('utf-8')
nul_index = encodable.find("\x00")
if nul_index >= 0:
error = UnicodeEncodeError("NUL-terminated utf-8", encodable, nul_index, nul_index + 1, "NUL not allowed")
error_handler = codecs.lookup_error(errors)
replacement, _ = error_handler(error)
assert isinstance(replacement, str), "handling a UnicodeEncodeError should return a str replacement"
encodable = encodable.replace("\x00", replacement)
return quote + encodable.replace(quote, quote * 2) + quote
def _escape_sqlite3_value(value: str, errors='strict') -> str:
return _escape_sqlite3(value, quote="'", errors=errors)
def _escape_sqlite3_identifier(value: str) -> str:
return _escape_sqlite3(value, quote='"', errors='strict')
def _create_tables():
table = _escape_sqlite3_identifier(SQLITEFTS_CONFIG.SQLITEFTS_TABLE)
# Escape as value, because fts5() expects
# string literal column names
column = _escape_sqlite3_value(SQLITEFTS_CONFIG.SQLITEFTS_COLUMN)
id_table = _escape_sqlite3_identifier(SQLITEFTS_CONFIG.SQLITEFTS_ID_TABLE)
tokenizers = _escape_sqlite3_value(SQLITEFTS_CONFIG.SQLITEFTS_TOKENIZERS)
trigger_name = _escape_sqlite3_identifier(f"{SQLITEFTS_CONFIG.SQLITEFTS_ID_TABLE}_ad")
with SQLITEFTS_CONFIG.get_connection() as cursor:
# Create a contentless-delete FTS5 table that indexes
# but does not store the texts of snapshots
try:
cursor.execute(
f"CREATE VIRTUAL TABLE {table}"
f" USING fts5({column},"
f" tokenize={tokenizers},"
" content='', contentless_delete=1);"
)
except Exception as e:
msg = str(e)
if 'unrecognized option: "contentlessdelete"' in msg:
sqlite_version = getattr(sqlite3, "sqlite_version", "Unknown")
raise RuntimeError(
"SQLite full-text search requires SQLite >= 3.43.0;"
f" the running version is {sqlite_version}"
) from e
else:
raise
# Create a one-to-one mapping between ArchiveBox snapshot_id
# and FTS5 rowid, because the column type of rowid can't be
# customized.
cursor.execute(
f"CREATE TABLE {id_table}("
" rowid INTEGER PRIMARY KEY AUTOINCREMENT,"
" snapshot_id char(32) NOT NULL UNIQUE"
");"
)
# Create a trigger to delete items from the FTS5 index when
# the snapshot_id is deleted from the mapping, to maintain
# consistency and make the `flush()` query simpler.
cursor.execute(
f"CREATE TRIGGER {trigger_name}"
f" AFTER DELETE ON {id_table} BEGIN"
f" DELETE FROM {table} WHERE rowid=old.rowid;"
" END;"
)
def _handle_query_exception(exc: Exception):
message = str(exc)
if message.startswith("no such table:"):
raise RuntimeError(
"SQLite full-text search index has not yet"
" been created; run `archivebox update --index-only`."
)
else:
raise exc
class SqliteftsSearchBackend(BaseSearchBackend):
name: str = 'sqlite'
docs_url: str = 'https://www.sqlite.org/fts5.html'
@staticmethod
def index(snapshot_id: str, texts: List[str]):
text = ' '.join(texts)[:SQLITEFTS_CONFIG.SQLITE_LIMIT_LENGTH]
table = _escape_sqlite3_identifier(SQLITEFTS_CONFIG.SQLITEFTS_TABLE)
column = _escape_sqlite3_identifier(SQLITEFTS_CONFIG.SQLITEFTS_COLUMN)
id_table = _escape_sqlite3_identifier(SQLITEFTS_CONFIG.SQLITEFTS_ID_TABLE)
with SQLITEFTS_CONFIG.get_connection() as cursor:
retries = 2
while retries > 0:
retries -= 1
try:
# If there is already an FTS index rowid to snapshot_id mapping,
# then don't insert a new one, silently ignoring the operation.
# {id_table}.rowid is AUTOINCREMENT, so will generate an unused
# rowid for the index if it is an unindexed snapshot_id.
cursor.execute(
f"INSERT OR IGNORE INTO {id_table}(snapshot_id) VALUES({SQLITEFTS_CONFIG.SQLITE_BIND})",
[snapshot_id])
# Fetch the FTS index rowid for the given snapshot_id
id_res = cursor.execute(
f"SELECT rowid FROM {id_table} WHERE snapshot_id = {SQLITEFTS_CONFIG.SQLITE_BIND}",
[snapshot_id])
rowid = id_res.fetchone()[0]
# (Re-)index the content
cursor.execute(
"INSERT OR REPLACE INTO"
f" {table}(rowid, {column}) VALUES ({SQLITEFTS_CONFIG.SQLITE_BIND}, {SQLITEFTS_CONFIG.SQLITE_BIND})",
[rowid, text])
# All statements succeeded; return
return
except Exception as e:
if str(e).startswith("no such table:") and retries > 0:
_create_tables()
else:
raise
raise RuntimeError("Failed to create tables for SQLite FTS5 search")
@staticmethod
def search(text: str) -> List[str]:
table = _escape_sqlite3_identifier(SQLITEFTS_CONFIG.SQLITEFTS_TABLE)
id_table = _escape_sqlite3_identifier(SQLITEFTS_CONFIG.SQLITEFTS_ID_TABLE)
with SQLITEFTS_CONFIG.get_connection() as cursor:
try:
res = cursor.execute(
f"SELECT snapshot_id FROM {table}"
f" INNER JOIN {id_table}"
f" ON {id_table}.rowid = {table}.rowid"
f" WHERE {table} MATCH {SQLITEFTS_CONFIG.SQLITE_BIND}",
[text])
except Exception as e:
_handle_query_exception(e)
snap_ids = [row[0] for row in res.fetchall()]
return snap_ids
@staticmethod
def flush(snapshot_ids: Iterable[str]):
snapshot_ids = list(snapshot_ids) # type: ignore[assignment]
id_table = _escape_sqlite3_identifier(SQLITEFTS_CONFIG.SQLITEFTS_ID_TABLE)
with SQLITEFTS_CONFIG.get_connection() as cursor:
try:
cursor.executemany(
f"DELETE FROM {id_table} WHERE snapshot_id={SQLITEFTS_CONFIG.SQLITE_BIND}",
[snapshot_ids])
except Exception as e:
_handle_query_exception(e)
SQLITEFTS_SEARCH_BACKEND = SqliteftsSearchBackend()
class SqliteftsSearchPlugin(BasePlugin):
app_label: str ='sqlitefts'
verbose_name: str = 'SQLite FTS5 Search'
hooks: List[InstanceOf[BaseHook]] = [
SQLITEFTS_CONFIG,
SQLITEFTS_SEARCH_BACKEND,
]
PLUGIN = SqliteftsSearchPlugin()
# PLUGIN.register(settings)
DJANGO_APP = PLUGIN.AppConfig