On May 25, 9:24 pm, Allard <[email protected]> wrote: > Comet is a nice way to get this done but I wonder how to implement > comet efficiently in web2py.
I have never used comet but I do not see any major problem > Massimo, does web2py use a threadpool > under the hood? For comet you would then quickly run out of threads. The web server creates a thread pool. for stand alone web2py that would be Rocket. You do not run out of them any more than any other web app. > If you'd try to do this with a thread per connection things would get > out of hand pretty quickly so the best way is doing the work > asynchronously like Orbited. Alternatives would be using one of the > contemporary Python asynchronous libraries. These libraries provide > monkey patching of synchronous calls like your url fetching. Some > suggestions: > > Gevent: now with support of Postgress, probably the fastest out there > Eventlet: used at Lindenlab / Second Life > Concurrence: with handy async mysql interface > Tornado: full async webserver in Python > > Massimo: what do you think of an asynchronous model for web2py? It'd > be great to to have asynchronous capabilities. I am writing an app > that will require quite a bit of client initiated background > processing (sending emails, resizing images) which I would rather hand > off to a green thread and not block one the web2py threads. Curious > about your thoughts. I do not think we can use async IO with web2py. async IO as far as I understand would require a different programming style. Anyway, if you have a working proof of concept I would like to see it. Massimo > > BTW - my first post here. Started to use for web2py for a community > site and enjoy working in it a lot! Great work. > > On May 25, 9:39 pm, Candid <[email protected]> wrote: > > > Well, actually there is a way for the server to trigger an action in > > the browser. It's called comet. Of course under the hood it's > > implemented on top of http, so it's browser who initiates request, but > > from the developer perspective it looks like there is dual channel > > connection between the browser and the server, and they both can send > > messages to each other asynchronously. There are several > > implementation of comet technology. I've used Orbited (http:// > > orbited.org/) and it worked quite well for me. > > > On May 25, 9:00 pm, mdipierro <[email protected]> wrote: > > > > I would use a background process that does the work and adds the items > > > to a database table. The index function would periodically refresh or > > > pull an updated list via ajax from the database table. there is no way > > > for te server to trigger an action in the browser unless 1) the > > > browser initiates it or 2) the client code embeds an ajax http server. > > > I would stay away from 1 and 2 and > > > use reload of ajax. > > > > On May 25, 5:33 pm, Giuseppe Luca Scrofani <[email protected]> > > > wrote: > > > > > Hi all, as promised I'm here to prove you are patient and nice :) > > > > I' have to make this little app where there is a function that read > > > > the html content of several pages of another website (like a spider) > > > > and if a specified keyword is found the app refresh a page where there > > > > is the growing list of "match". > > > > Now, the spider part is already coded, is called search(), it uses > > > > twill to log in the target site, read the html of a list of pages, > > > > perform some searching procedures and keep adding the result to a > > > > list. I integrated this in a default.py controller and make a call in > > > > def index(): > > > > This make the index.html page loading for a long time, because now it > > > > have to finish to scan all pages before return all results. > > > > What I want to achieve is to automatically refresh index every 2 > > > > second to keep in touch with what is going on, seeing the list of > > > > match growing in "realtime". Even better, if I can use some sort of > > > > ajax magic to not refresh the entire page... but this is not vital, a > > > > simple page refresh would be sufficient. > > > > Question is: I have to use threading to solve this problem? > > > > Alternative solutions? > > > > I have to made the list of match a global to read it from another > > > > function? It would be simpler if I made it write a text file, adding a > > > > line for every match and reading it from the index controller? If I > > > > have to use thread it will run on GAE? > > > > > Sorry for the long text and for my bad english :) > > > > > gls
