From 14f34b1f64a667bf4a146e8579f95c5d308a1f77 Mon Sep 17 00:00:00 2001 From: drebs Date: Thu, 8 Jan 2015 18:57:38 -0200 Subject: Retry on SQLCipher timeout (#6625). --- client/src/leap/soledad/client/adbapi.py | 45 ++++++++++++++++++++++++++++++-- 1 file changed, 43 insertions(+), 2 deletions(-) (limited to 'client/src/leap') diff --git a/client/src/leap/soledad/client/adbapi.py b/client/src/leap/soledad/client/adbapi.py index f0b7f182..7ad10db5 100644 --- a/client/src/leap/soledad/client/adbapi.py +++ b/client/src/leap/soledad/client/adbapi.py @@ -21,20 +21,37 @@ It uses twisted.enterprise.adbapi. import re import os import sys +import logging from functools import partial +from threading import BoundedSemaphore from twisted.enterprise import adbapi from twisted.python import log from zope.proxy import ProxyBase, setProxiedObject +from pysqlcipher.dbapi2 import OperationalError from leap.soledad.client import sqlcipher as soledad_sqlcipher +logger = logging.getLogger(name=__name__) + + DEBUG_SQL = os.environ.get("LEAP_DEBUG_SQL") if DEBUG_SQL: log.startLogging(sys.stdout) +""" +How long the SQLCipher connection should wait for the lock to go away until +raising an exception. +""" +SQLCIPHER_CONNECTION_TIMEOUT = 10 + +""" +How many times a SQLCipher query should be retried in case of timeout. +""" +SQLCIPHER_MAX_RETRIES = 10 + def getConnectionPool(opts, openfun=None, driver="pysqlcipher"): """ @@ -58,7 +75,8 @@ def getConnectionPool(opts, openfun=None, driver="pysqlcipher"): openfun = partial(soledad_sqlcipher.set_init_pragmas, opts=opts) return U1DBConnectionPool( "%s.dbapi2" % driver, database=opts.path, - check_same_thread=False, cp_openfun=openfun) + check_same_thread=False, cp_openfun=openfun, + timeout=SQLCIPHER_CONNECTION_TIMEOUT) class U1DBConnection(adbapi.Connection): @@ -154,6 +172,10 @@ class U1DBConnectionPool(adbapi.ConnectionPool): """ Execute a U1DB query in a thread, using a pooled connection. + Concurrent threads trying to update the same database may timeout + because of other threads holding the database lock. Because of this, + we will retry SQLCIPHER_MAX_RETRIES times and fail after that. + :param meth: The U1DB wrapper method name. :type meth: str @@ -162,7 +184,26 @@ class U1DBConnectionPool(adbapi.ConnectionPool): :rtype: twisted.internet.defer.Deferred """ meth = "u1db_%s" % meth - return self.runInteraction(self._runU1DBQuery, meth, *args, **kw) + semaphore = BoundedSemaphore(SQLCIPHER_MAX_RETRIES - 1) + + def _run_interaction(): + return self.runInteraction( + self._runU1DBQuery, meth, *args, **kw) + + def _errback(failure): + failure.trap(OperationalError) + if failure.getErrorMessage() == "database is locked": + should_retry = semaphore.acquire(False) + if should_retry: + logger.warning( + "Database operation timed out while waiting for " + "lock, trying again...") + return _run_interaction() + return failure + + d = _run_interaction() + d.addErrback(_errback) + return d def _runU1DBQuery(self, trans, meth, *args, **kw): """ -- cgit v1.2.3