2007/9/20, Phil Christensen <phil@bubblehouse.org>:
On Sep 20, 2007, at 7:39 AM, Werner Thie wrote:
Hi all
While using mySQL V 5.0.33 and MySQL-python-1.2.2 with twisted/ adbapi with the following connection params [snip snip snip] I noticed (2006, 'MySQL server has gone away') errors, which seem to be not recoverable from an adbapi standpoint. [snip snip snip] Questions: - are there any adverse effects in applying this patch and setting reconnect: 1 in DB_ARGS?
- is there a better, safer way to avoid this nasty error?
Thxs, Werner
I believe this is what the 'cp_reconnect' keyword argument to the ConnectionPool constructor does.
In case it helps: The cp_reconnect keyword is mandatory but not sufficient for what I've experienced. At least with MySQL server version 4.1.7, a disconnection raises a generic OperationalError which one has to parse to know what actually happened. Hence the need to subclass ConnectionPool and surcharge _runInteraction for adding the ability to retry on MySQL connection lost. Or maybe is there a better way to do that? ---- CODE ---- import twisted.enterprise.adbapi try: from MySQLdb import OperationalError except ImportError: OperationalError = None class EnhancedConnectionPool(adbapi.ConnectionPool): def _runInteraction(self, *args, **kwargs): try: d = abdapi.ConnectionPool._runInteraction(self, *args, **kwargs) except OperationalError, e: errormsg = str(e).lower() messages = ( "lost connection to mysql server during query", "server has gone away" ) for msg in messages: if msg in errormsg: d = abdapi.ConnectionPool._runInteraction(self, *args, **kwargs) return d else: raise return d ---- / CODE ----