On Sat, Nov 28, 2015 at 10:41 PM, Glyph Lefkowitz <gl...@twistedmatrix.com> wrote: > > On Nov 25, 2015, at 04:54, Oon-Ee Ng <ngoonee.t...@gmail.com> wrote: > > On Tue, Nov 24, 2015 at 11:03 AM, Oon-Ee Ng <ngoonee.t...@gmail.com> wrote: > > And furthermore that when I do that, callRemote no longer returns a > deferred (which makes sense, really) and instead gets a None. One more > check before I add my default errBacks then. Optimised network traffic > sounds positive, at the least (I assume this means one less > transmission since it effectively makes the AMP one-way for the > messages which have this set to False). > > > Just realized, requiresAnswer=False means I can't add errBacks, which > means there's no way to handle a receiver-side error. Is this correct? > > > That is correct. But you shouldn't want to handle errors there :-). Don't > think of a requiresAnswer=False command as an optimization; instead, think > of it as a piece of information being relayed. > > For example; consider an HTTP stream. The client sends a request. If the > server has an error, it sends an error code. Then, the server sends the > entity-body, one chunk at a time. > > The client has to process each of those chunks one after another. If the > server sends a chunk and the client encounters an error, there's nothing for > the server to do; the client has no way to communicate it and it can just > disconnect. You would use requiresAnswer=False (as you are already doing in > your case) to send a chunk of data like those entity-body chunks, which > ought not to be a message that... requires an answer. It's just a way of > encoding some data on the connection. > > Make sense?
Yeah, especially in the context of a HTTP stream. In other words requiresAnswer=False is just a way of labelling a messages as 'fire-and-forget'. I'll have to think a bit more about which of my messages actually need answers then. For some, I do need an indication of success (or failure), if only so I can try re-sending. Those won't get the flag then. _______________________________________________ Twisted-Python mailing list Twisted-Python@twistedmatrix.com http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python
