75 lines
2.1 KiB
Python
75 lines
2.1 KiB
Python
# -*- coding: utf-8 -*-
|
|
# Copyright 2015 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.
|
|
|
|
from synapse.storage.prepare_database import (
|
|
prepare_database, prepare_sqlite3_database
|
|
)
|
|
|
|
import struct
|
|
|
|
|
|
class Sqlite3Engine(object):
|
|
single_threaded = True
|
|
|
|
def __init__(self, database_module):
|
|
self.module = database_module
|
|
|
|
def check_database(self, txn):
|
|
pass
|
|
|
|
def convert_param_style(self, sql):
|
|
return sql
|
|
|
|
def on_new_connection(self, db_conn):
|
|
self.prepare_database(db_conn)
|
|
db_conn.create_function("rank", 1, _rank)
|
|
|
|
def prepare_database(self, db_conn):
|
|
prepare_sqlite3_database(db_conn)
|
|
prepare_database(db_conn, self)
|
|
|
|
def is_deadlock(self, error):
|
|
return False
|
|
|
|
def is_connection_closed(self, conn):
|
|
return False
|
|
|
|
def lock_table(self, txn, table):
|
|
return
|
|
|
|
|
|
# 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
|