106 lines
3.3 KiB
Python
106 lines
3.3 KiB
Python
# -*- coding: utf-8 -*-
|
|
# Copyright 2015, 2016 OpenMarket Ltd
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
import struct
|
|
import threading
|
|
|
|
from synapse.storage.prepare_database import prepare_database
|
|
|
|
|
|
class Sqlite3Engine(object):
|
|
single_threaded = True
|
|
|
|
def __init__(self, database_module, database_config):
|
|
self.module = database_module
|
|
|
|
# The current max state_group, or None if we haven't looked
|
|
# in the DB yet.
|
|
self._current_state_group_id = None
|
|
self._current_state_group_id_lock = threading.Lock()
|
|
|
|
@property
|
|
def can_native_upsert(self):
|
|
"""
|
|
Do we support native UPSERTs? This requires SQLite3 3.24+, plus some
|
|
more work we haven't done yet to tell what was inserted vs updated.
|
|
"""
|
|
return self.module.sqlite_version_info >= (3, 24, 0)
|
|
|
|
def check_database(self, txn):
|
|
pass
|
|
|
|
def convert_param_style(self, sql):
|
|
return sql
|
|
|
|
def on_new_connection(self, db_conn):
|
|
prepare_database(db_conn, self, config=None)
|
|
db_conn.create_function("rank", 1, _rank)
|
|
|
|
def is_deadlock(self, error):
|
|
return False
|
|
|
|
def is_connection_closed(self, conn):
|
|
return False
|
|
|
|
def lock_table(self, txn, table):
|
|
return
|
|
|
|
def get_next_state_group_id(self, txn):
|
|
"""Returns an int that can be used as a new state_group ID
|
|
"""
|
|
# We do application locking here since if we're using sqlite then
|
|
# we are a single process synapse.
|
|
with self._current_state_group_id_lock:
|
|
if self._current_state_group_id is None:
|
|
txn.execute("SELECT COALESCE(max(id), 0) FROM state_groups")
|
|
self._current_state_group_id = txn.fetchone()[0]
|
|
|
|
self._current_state_group_id += 1
|
|
return self._current_state_group_id
|
|
|
|
@property
|
|
def server_version(self):
|
|
"""Gets a string giving the server version. For example: '3.22.0'
|
|
|
|
Returns:
|
|
string
|
|
"""
|
|
return "%i.%i.%i" % self.module.sqlite_version_info
|
|
|
|
|
|
# Following functions taken from: https://github.com/coleifer/peewee
|
|
|
|
|
|
def _parse_match_info(buf):
|
|
bufsize = len(buf)
|
|
return [struct.unpack("@I", buf[i : i + 4])[0] for i in range(0, bufsize, 4)]
|
|
|
|
|
|
def _rank(raw_match_info):
|
|
"""Handle match_info called w/default args 'pcx' - based on the example rank
|
|
function http://sqlite.org/fts3.html#appendix_a
|
|
"""
|
|
match_info = _parse_match_info(raw_match_info)
|
|
score = 0.0
|
|
p, c = match_info[:2]
|
|
for phrase_num in range(p):
|
|
phrase_info_idx = 2 + (phrase_num * c * 3)
|
|
for col_num in range(c):
|
|
col_idx = phrase_info_idx + (col_num * 3)
|
|
x1, x2 = match_info[col_idx : col_idx + 2]
|
|
if x1 > 0:
|
|
score += float(x1) / x2
|
|
return score
|