On Oct 5, 4:08 pm, Alessandro Molina <[email protected]> wrote: > On Wed, Oct 5, 2011 at 5:36 AM, Sean DiZazzo <[email protected]> wrote: > > Hi,I have a Turbogears 2.1.2 app that kicks off a long running > > parallel task. The task is run in many threads and on several > > machines,and they all need to use the model to update the database. > > What are the best practices for running DBSessions in threads? I > > You can try tgext.asyncjob it might do most of the work for you. > It will manage the session for you letting you just use the > model.DBSession inside the asynchronous threads. > > About the session, by default TurboGears already provides a > sessionmaker which will create one scoped_session for each thread that > will try to use the DBSession object. The main issue is that TG > patches the session to use a different transactions manager which runs > inside the TG middleware stack by committing and reverting session > whenever is necessary. When you use the session outside of a request > anyway this middleware is not in place and so you will have to manage > the session yourself. By default tgext.asyncjob implements a worker > that behaves like TG, committing the session at the end of the async > function and reverting it in case of an exception.
I have seen that code before and it's very nice. It won't quite work on my project, but I will try to steal the relevant transaction parts. Parts of my code are not run in the typical Turbogears controller and run as daemons on other boxes. I have tried to create the same environment on those client boxes, but when I switched the code to use the DBSession from tg, I started getting errors like: UnboundExecutionError: Could not locate a bind configured on mapper Mapper|Job|jobs, SQL expression or this Session I think some part of the environment is not set correctly. What is the minimum I need to do to be able to use the DBSession without these errors? I see lots of posts regarding this issue. Would following this solve the issue? http://permalink.gmane.org/gmane.comp.web.turbogears/43261 or is there an alternative suggested way? Thanks! ~Sean -- You received this message because you are subscribed to the Google Groups "TurboGears" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/turbogears?hl=en.
