Twisted MySQL Protocol implementation v0.4

With thanks to _habnabit for the intial code (which did the vast majority of the heavy lifting) and his qbuf library, and Dev0n for DATETIME and affected_rows support on the result of a runOperation.

PREREQUISITES:

* qbuf (a Python C-extension)

FEATURES: * Connects lazily to MySQL and disconnects if the connection is left idle longer than idle_timeout * Reconnects on errors when there are pending queries (including user-configurable errors with temporary_error_strings=[...] in the constructor) * Now has unit tests * Support escaping arguments with '%s' style syntax * Actually use the database=foo argument passed into the constructor (need to set CLIENT_* flag) * Code comments, and a lot of tidying up * Fixed insidious bug relating to disconnection which resulted in corrupt/duplicated results getting sent on the wrong deferreds * MySQL DATETIME fields now show up correctly (XXXX-XX-XX XX:XX:XX). * When a runOperation is called, the deferred now returns the a dictionary with the following: - {'insert_id': int, 'affected_rows': int, 'message': str, 'warning_count': int, 'server_status': int}

TODO:

* Transaction support
* Stored queries
* Connection pool
* DBAPI support - see http://www.python.org/dev/peps/pep-0249/
* Test against more than just the version of MySQL 5.1 which happened
  to be installed on my ThinkPad :-)

EXAMPLE USAGE:

import sys

from twisted.internet import reactor, defer from twisted.python import log

from txmysql import client

log.startLogging(sys.stdout)

def example(): conn = client.MySQLConnection('127.0.0.1', 'root', secrets.MYSQL_ROOT_PASS, idle_timeout=120, connect_timeout=30) # This gets remembered and re-run if the connection needs reconnection d = conn.selectDb("foo") def selectedDb(ignored): return conn.runOperation("insert into bar set baz='bash'") d.addCallback(selectedDb) def doneInsert(ignored): return conn.runQuery("select * from bar") d.addCallback(doneInsert) def gotResult(data): print repr(data) d.addCallback(gotResult) def handleFailure(reason): # reason can be a MySQLError with message, errno, sqlstate, query print reason d.addErrback(handleFailure) return d

if name == "main": reactor.callWhenRunning(example) reactor.run()

SHAMELESS PLUG:

txMySQL is used in production by Hybrid Web Cluster, which is an n-redundant web cluster with no single point of failure, which uses ZFS replication to eliminate shared storage in loosely coupled, geographically distributed web hosting environments. Entire data centres can fail and everything carries on running, with data loss and downtime measured in seconds, not hours or days, and stress caused by hardware or network connectivity failures a thing of the past.

It runs on dedicated hardware and/or cloud infrastructure, enabling hybrid setups where you use dedicated hardware for performance and cloud infrastructure for ease-of-provisioning, all within the same cluster.

Check it out at http://www.hybrid-cluster.com/. If you are involved with hosting websites or know anyone who is, please spread the word :-)

If you just want web hosting for your own site, we offer rock solid hosting based on the aforementioned technology at http://www.hybrid-sites.com/.

QUESTIONS?

Email luke [at] hybrid-logic [dot] co [dot] uk

TxMySQL

Install / Use

README