On 12/03/2014 08:53, Laurens Van Houtven wrote:
Twisted has a thing called Cyclone, which I hear (but that's only hearsay) gives you Tornado's API on top of twisted, so you get all of the stuff below for free.
From my side, I'm looking to experimentally build a network testing tool that will need to speak a fair few protocols, both classic tcp and multicast-based, and have a web api living on top of it that most likely will have a websocket for pumping data to the browser. It'll also need to write out JUnit-compatible xml results, but that's like the easiest bit ;-)
I don't know which protocols you are interested in specifically;
Aiming low (insert sarcastic look here), here's the first few: http://cdn.batstrading.com/resources/participant_resources/BATS_Europe_FIX_S... http://cdn.batstrading.com/resources/participant_resources/BATS_Europe_Binar... http://cdn.batstrading.com/resources/participant_resources/BATS_Europe_PITCH... http://cdn.batstrading.com/resources/participant_resources/BATS_Europe_MC_PI...
Twisted has a third party project called txsockjs which works excellently, both by itself and in the context of other (HTTP) resources. sockjs is a protocol which is basically "websockets, damnit", even when the consumer is a bad browser like IE6.
Thankfully, I only have to support sane browsers...
Twisted comes with a threadpool-backed WSGI server. (When I say threadpool-backed I mean that the WSGI requests are handled in threads; the IO itself of course comes from the Twisted reactor).
Yeah, I remember that, and I remember liking it :-)
I find twisted to be a great tool for writing protocol implementations. I have written tools for querying all sorts of gnarly proprietary protocols over all sorts of gnarly transports (packet radio; it's totally a thing), and more recently for doing crazy things like multiplexing stream transports over existing RPC protocols. (Like, you see a local port come up, and that actually creates a virtual stream connection over an existing RPC thing to some virtual server on the other end of the wire: https://www.youtube.com/watch?v=W_jEIvugwes).
Cool!
Twisted has had so many people write so many protocols in it that also the testing tools (MemoryReactor, StringTransport) are great. Especially if you are writing something very close to a wire protocol you will undoubtedly enjoy those amenities. There's also tons of composable things for receiving delimited lines, nestrings, etc. It's hard to tell what you will be looking for since I don't know details about your protocol, but having written more than a few protocol implementations I'm going to wager a guess and say Twisted has it or a third party thing for twisted has it.
Yep, certainly sounds good. I guess I have concerns about discoverability and making sure I'm picking the right things to use rather than re-implementing things when I don't need to. What's the best way for me to find things I should be using? I guess my fallback position is to ask lots of clueless questions on this list and hope I don't annoy to many people, is that viable?
Twisted, emphatically and without reservation, for all the above reasons. It's stable. All the stuff you need has been tried and tested extensively in production. It runs on PyPy, and usually a damn sight faster than on CPython, too.
Didn't know about the PyPy thing, that will be interesting if I ever hit performance problems...
A common criticism of Twisted is that it "takes over" your codebase. I am speaking at PyCon in about a month to demonstrate that that isn't true. (It just looks that way, because once people use it, they don't want to go back... ;-))
Gutted I can't make it to PyCon this year, look forward to watching the video! Chris -- Simplistix - Content Management, Batch Processing & Python Consulting - http://www.simplistix.co.uk