It's been a while since I've filed one of these, I'm afraid. Fall was a mix of deep discussion that wasn't complete yet, conferences and other schedule conflicts that slowed us down, and then the holidays. I didn't want to present a discussion that was still actively engaged in sausage making and still subject to active change on a moment's notice, so, well, here we are. However, I'm going to try and summarize the various changes we've made to PSR-14 in the last few months now that we're settled down again and, I think, in a very good place. This summary is not chronological, but in the order I think makes the most sense collectively from our last update.
* After a great deal of discussion, we decided to remove the Message/Notifier portion of the spec. In the end, we decided that there just wasn't enough existing prior art for us to analyze and determine good edge case handling for that approach. In particular, our nominal target for that pathway, Symfony's Messenger component, on further review we determined to be a completely different use case anyway that was not even what we were targeting here, and thus irrelevant to PSR-14 entirely. * That in turn allowed us to remove several nouns from the spec (yay), which meant that we could fold the "Event" term back into the only "thing that gets passed". The "Task" terminology is now gone. There's just Events, Dispatchers, and Providers. * However, after looking into Laravel in more detail and examining the way Listener callables and Providers were defined already, we realized that the bulk of the use cases for Messages -- that is, potentially deferrable/ asynchronous unidirectional communication -- could be handled in a similar fashion to Laravel's "ShouldQueue" marker interface on the *listener* (not the event). Specifically, listeners are abstractly defined enough that they can still defer actions themselves, or Providers can add a deferring wrapper themselves, in appropriate situations. That is, we can cover just as many use cases as before but in a more flexible way with less ceremony. * With the simplified set of interfaces, there is now little value to the marker interface as there would be only one. However, we still wanted to provide at least some level of type safety as that is a key component of any specification. To that end, we have removed the EventInterface marker type. * However, we have replaced it with an "object" type hint. That in turn necessitates increasing the version requirement to PHP 7.2. This was a difficult decision, but in the end we decided that it not only made the spec better but it *improved* backward compatibility for existing implementations thanks to PHP 7.2's allowance to drop type hints in subclasses; that allows existing implementations (in particular Symfony and Laravel) to support both PSR-14 and their current APIs in parallel without a syntax violation. We also determined that, at least within the expected release schedules of Symfony and Zend Framework, a PHP 7.2 requirement is only a minor delay in their ability to implement the specification. Given that many previous specifications have been hindered by targeting "in the wild but soon to be deprecated" PHP versions that limited their ability to leverage new language features, we determined that the specification was best served by targeting the already- legacy PHP version rather than a version that is already only barely supported. * Because of all of the above, we were also able to collapse the spec back to a single composer package rather than the previous 3, which is always a win. The specification text is now up to date, modulo a few bits of fiddling we're still working on that shouldn't have any impact on the interface signatures themselves: https://github.com/php-fig/fig-standards/blob/master/proposed/event-dispatcher.md https://github.com/php-fig/fig-standards/blob/master/proposed/event-dispatcher-meta.md The following composer package for the interfaces themselves is also ready to use, on the 0.7 tag: https://packagist.org/packages/psr/event-dispatcher And a corresponding util package, at the 0.7.1 tag (sorry): https://packagist.org/packages/fig/event-dispatcher-util (We'll add a few more utilities to the util package before it actually ships, mostly provider tooling.) And a fully complete implementation to try is available here (0.7.1 tag): https://packagist.org/packages/crell/tukio We're collectively pretty happy with where we are at this point, and encourage all interested parties to try out the code above. We're planning another meeting for next week and if no other issues are raised by then plan to call a Readiness Vote at that time. --Larry Garfield, PSR-14 Editor -- You received this message because you are subscribed to the Google Groups "PHP Framework Interoperability Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/php-fig/5304503.rBvXg8NvYf%40vulcan. For more options, visit https://groups.google.com/d/optout.
signature.asc
Description: This is a digitally signed message part.
