John Dickinson said: > I breifly played around with using Warren Smith's DBConnectionPool class > on some stuff (I'm surprised he hasn't responded in this thread yet).
I guess I DO usually chime in on these type of discussions, at least enough for you to wonder why I haven't yet this time:-). I admit to being a little weary of discussing this. I guess I need to write up something on the Wiki and then just point people to it. This is a common enough question that perhaps something should be included in the docs in the next release of Webware. Perhaps I could even get an updated version of DBConnectionPool into the MiscUtils section of the Webware source. There was someone else recently that was inquiring about a pooling module and I offered to collaborate with them on improving DbConnectionPool. I never did get a response, however. > I think you can get his pooling module from the webware sandbox. Here is the URL: http://cvs.sourceforge.net/viewcvs.py/webware-sandbox/Sandbox/wsmith323/ > His pooling > module allows for a separate thread to run and handle some of the > connection management (old/stale connections). To implement it, I put some > of the setup in the sitepage (class level and module level). See my > example below. Anyone please correct me if I'm wrong in my implementation. > You're implementation looks OK. I assume you are calling the .close() method (to put the conneciton back in the pool) when you are done with the connection in each request. The destructor on the connection wrapper will call .close() if you forget to, but it is good form to call it explicitely. I noticed that you have commented out the call to .stopExpiration() in the destructor for the base servlet. I would remove it entirely, since I can't think of a good reason to ever call it, except maybe within a test suite. > > --== sitepage (DBtestpage.py) ==-- > from DbConnectionPool import DbConnectionPool > from WebKit.Page import Page > > #from pyPgSQL import PgSQL as db_mod > import sys > import PyIngres as db_mod > > maxPoolSize = 10 # 0 or None for unlimited > dbPool = DbConnectionPool(maxPoolSize, db_mod, > {'database':'foo','user':'bar'}) > dbPool.startExpiration(expireIntervalSeconds=10, maxIdleSeconds=20, > maxAgeSeconds=30, aggressiveExpiration=True) > > class DBtestpage(Page): > > def __init__(self): > global dbPool > > self._dbPool = dbPool > Page.__init__(self) > > def getDBPool(self): > return self._dbPool > > def writeContent(self): > #self.writeln('DBtestpage') > self.response().sendRedirect('DBtest.py') > > def __del__(self): > self.writeln('in __del__') > #self._dbPool.stopExpiration() > Page.__del__(self) > > > --== servlet page (DBtest.py) ==-- > from DBtestpage import DBtestpage > > class DBtest(DBtestpage): > def __init__(self): > DBtestpage.__init__(self) > def writeContent(self): > try: > conn = self.getDBPool().getConnection() > except: > # problem, bail > return > else: > self.writeln('successful.') > -- Warren Smith [EMAIL PROTECTED] ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click _______________________________________________ Webware-discuss mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/webware-discuss
