[Twisted-Python] A C/S Application over Internet

[Phil Christensen]

On Aug 27, 2009, at 10:57 AM, 陶艺夫 wrote:
> Thank you, Phil.
>
> Pyro has many examples, so I can understand it easily. I know  
> Twisted is great. I think your "switching" must mean something :) .
> So I decide to use twisted PB.


Great!

I also remembered one thing that I found was extremely useful when  
dealing with a GUI app that communicates over PB. Since PB assumes  
every remote method call will take an arbitrary amount of time to  
execute, you can delay the response from the client as long as you need.

For example, let's say the server sends a block of text to the client  
for editing. Your client-side function can create a Deferred, hold a  
reference to it somewhere, and return that from the client function.

PB won't actually send a response until you invoke the callback()  
method on that Deferred, so you can pop open a GUI window, let the  
user edit the text (or just sit there staring at it for an hour), and  
then trigger the callback when the user hits 'Save'.

Very useful, although I wrote some incredibly stupid code to emulate  
this long before I realized how easy it was ;-)

-phil