All that you ask can be done using the scheduler except that your app does not start the process, but submits a request to the scheduler. The scheduler runs the app when a worker is available. This is to prevent spikes in resource utilization when multiple processes start. The task can communicate with the app vid database and/or filesystem (which is ok but not 100% satisfactory). Web2py can monitor and kill running scheduler tasks.
This works well for most types of tasks but not for tasks that need a lot of IO with your application. I do not have a satisfactory solution in that case. You want the tasks to have some way to communicate asynchronously with the client and this present major issues, some related with security. On Friday, 1 February 2013 10:22:35 UTC-6, José Luis Redrejo Rodríguez wrote: > > Hi, This is a question that has been asked several times in the list, > and I have also had to implement this kind of app in the past. > Now I'm also facing to another application where I need to run a > resource_and_time_consuming process managed from web2py. > > The exact problem is: > - From a web page, a long process must be started > - The web page must be updated as the process is being done > - The web page must be able to cancel the process. > > In the past I have had to deal with the fact of sessions lockings: > web2py server doesn't react while the process is being executed. I've > solved this by using session.forget(response), but this solution > avoids the use of session variables to update the process in the > original web page. > > I've used background processes, queues, etc, These solutions work when > time is not an issue, but not when the synchronization between the > process and the webpage must be fast and accurate > > I wonder if someone has a definitive pattern to do this kind of action. > > Regards > José L. > -- --- You received this message because you are subscribed to the Google Groups "web2py-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to web2py+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
