Hello! On Tue, Feb 13, 2018 at 12:21:36PM +0000, Alessandro Ghedini wrote:
> On Fri, Feb 09, 2018 at 10:35:59AM +0300, Ruslan Ermilov wrote: > > On Thu, Feb 08, 2018 at 07:48:25PM +0000, Alessandro Ghedini wrote: > > > On Thu, Feb 08, 2018 at 10:00:27PM +0300, Maxim Dounin wrote: > > > > On Thu, Feb 08, 2018 at 04:52:59PM +0000, Alessandro Ghedini wrote: > > > > > > > > > # HG changeset patch > > > > > # User Alessandro Ghedini <[email protected]> > > > > > # Date 1518108716 0 > > > > > # Thu Feb 08 16:51:56 2018 +0000 > > > > > # Branch expose-push > > > > > # Node ID 1bb98b06d5536dfc80a407aabd8d06f9309f8df6 > > > > > # Parent a49af443656f2b65ca5de9d8cad5594f44e18ff7 > > > > > HTTP/2: expose function to push single resource to modules. > > > > > > > > > > This makes it possible for 3rd party modules to implement alternative > > > > > methods for deciding which resources to push to clients on a > > > > > per-request > > > > > basis (e.g. by parsing HTML from the response body, by using a custom > > > > > Link header parser, ...). > > > > > > > > > > No functional changes. > > > > > > > > Not sure this is a good idea. > > > > > > > > You may consider exposing a variable to be used in http2_push > > > > instead. > > > > > > Right, the problem is that as far as I can tell http2_push only supports a > > > single resource, even when a variable is used, so it wouldn't be possible > > > to > > > push multiple resources without specifying multiple http2_push directives, > > > each with its own variable, and even then you'd only have a fixed number > > > of > > > resources that can be pushed, which wouldn't work well when the number of > > > resources changes depending on each request/response. > > > > > > So in the end exposing the internal functions to modules seemed better > > > than > > > just trying to make http2_push support multiple resources per directive, > > > which would add complexity to NGINX itself rather than the external > > > modules > > > (though I can do that if you think it would be a better solution). > > > > We've also considered adding support for the X-Accel-Push header, but > > decided not to implement it at this time. If implemented, there could > > be multiple X-Accel-Push headers in the proxied response. > > That might work for us, but it's a somewhat awkward interface to use from > inside a module, so I'd still prefer something more direct, and as I said, > exposing the function to modules seemed the least invasive change to NGINX. > > Could you please expand a bit on why you think this might be a bad idea? > > In any case I can look into implementing X-Accel-Push support if you don't > plan on doing it yourself. I presonally think that X-Accel-Push is not needed and should not be added given we already have http2_push. Also, HTTP/2 push as a technology has enough design problems to introduce additional interfaces. If you want to use HTTP2 pushes from a module, consider either using http2_push with variables as previously suggested (right now you can use multiple http2_push directives if you want to push multiple resources), or adding "Link: rel=preload" headers and using http2_push_preload. -- Maxim Dounin http://mdounin.ru/ _______________________________________________ nginx-devel mailing list [email protected] http://mailman.nginx.org/mailman/listinfo/nginx-devel
