On Thu, Jun 8, 2017 at 3:32 PM, manuel miranda <manu.miran...@gmail.com> wrote: > Hello everyone, > > After using asyncio for a while, I'm struggling to find information about > how to support both synchronous and asynchronous use cases for the same > library. > > I.e. imagine you have a package for http requests and you want to give the > user the choice to use a synchronous or an asynchronous interface. Right now > the approach the community is following is creating separate libraries one > for each version. This is far from ideal for several reasons, some I can > think of: > > - Code duplication, most of the functionality is the same in both libraries, > only difference is the sync/async behaviors > - Some new async libraries lack functionality compared to their sync > siblings. Others will introduce bugs that the sync version already solved > long ago, etc. > - Different interfaces for the user for the same exact functionality. > > In summary, in some cases it looks like reinventing the wheel. So now comes > the question, is there any documentation, guide on what would be best > practice supporting this kind of duality?
I would say that this is something that we as a community are still figuring out. I really like the Sans-IO approach, and it's a really valuable piece of the solution, but it doesn't solve the whole problem by itself - you still need to actually do I/O, and this means things like error handling and timeouts that aren't obviously a natural fit to the Sans-IO approach, and this means you may still have some tricky code that can end up duplicated. (Or maybe the Sans-IO approach can be extended to handle these things too?) There are active discussions happening in projects like urllib3 [1] and packaging [2] about what the best strategy to take is. And the options vary a lot depending on whether you need to support python 2 etc. If you figure out a good approach I think everyone would be interested to hear it :-) -n [1] https://github.com/shazow/urllib3/pull/1068#issuecomment-294422348 [2] Here's the same API implemented three different ways: Using deferreds: https://github.com/pypa/packaging/pull/87 "traditional" sans-IO: https://github.com/pypa/packaging/pull/88 Using the "effect" library: https://github.com/dstufft/packaging/pull/1 -- Nathaniel J. Smith -- https://vorpus.org _______________________________________________ Async-sig mailing list Async-sig@python.org https://mail.python.org/mailman/listinfo/async-sig Code of Conduct: https://www.python.org/psf/codeofconduct/
