sribe
[error] Ranch protocol :error (:cowboy_protocol) of listener UrlFetcher.Endpoint.HTTP terminated
** (exit) :undef
15:07:19.288 [error] Ranch listener ‘Elixir.UrlFetcher.Endpoint.HTTP’ connection process start failure; cowboy_protocol:start_link/4 crashed with reason: error:undef
Any idea where to look? I have renamed some files & modules, which is of course an immediate suspect for this error. But I’ve double-checked everything; deleted the _build folder; and I don’t see anything wrong in the project.
(I have added gRPC modules; but I don’t see how they could affect this.)
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OvermindDL1
Huh, that is entirely new to me. Any chance on posting this project on github or preferably a simplified version that reproduces this error?
sribe
Going through my changes step-by-step: it’s caused by the Cowboy branch from Tony Han as part of his gRPC support.
So I’m going to dig into that repo and look at his commits now.
sribe
The plug/phoenix forks do not work with the gRPC stuff straight out of the box, and I don’t think I can take the time right now to fix that.
I’m trying to implement a super-simple API (1 call), so I think my best bet is probably to start with gRPC, then set up routing of my 1 endpoint from Cowboy to a handler, without Phoenix & Plug.
OvermindDL1
Oh I hope that adds HTTP2 support… >.<
We need a way in phoenix to specify to the plug to send other data/files to the client along with the page (page first though) ahead-of-time…
sribe
Yes, Cowboy 2 adds HTTP2 support, and that is in fact the source of the API incompatibility–new HTTP features.
tony612
Hi, just saw this. I just use the commit in this PR to support Trailers in HTTP/2 http trailers support by IgorKarymov · Pull Request #1020 · ninenines/cowboy · GitHub . But I don’t think it’s related to your problem. And maybe it’s not a good idea to use Cowboy2 with Phoenix before the stable version is released.
seeekr
What’s the status of cowboy 2.x with phoenix? I’m trying to use your grpc library in a phoenix 1.3 project, getting "ranch protocol :error"s.
OvermindDL1
Current Plug/Phoenix master has Cowboy2 support, they are just finishing refining it but you can use it now if you want to play with it.
Darim
How exactly should they all be specified in mix.exs?
OvermindDL1
Use the master versions, they have not had a release yet.