Hi Joe, If you properly cancel the request stream I don't think that you need to consume it with a black hole sink.
B/ On 29 January 2015 at 11:30:32, Joe Edwards ([email protected]) wrote: Thanks for the explanation. Unfortunately I don't control the clients so it sounds like we have to send a 'Connection: Close' header and hope the client aborts the request for us, otherwise we have to read (and discard) the whole request to ensure the client will read the response. That's a bit of a pain, but I suppose it's really the client's problem if they insist on ignoring the response until they've uploaded their whole 2GB message. Re: akka-http Is it true once the stream processing the request is cancelled we still need to attach a (blackhole) sink to the request stream, otherwise the back-pressure may simply stall the client indefinitely? On Wednesday, 28 January 2015 19:33:58 UTC, Daniel Armak wrote: I can't comment on akka-http, but here's my understanding of the HTTP spec. It's certainly legal to send a response before receiving the request entity, but the client isn't obligated to start reading the response before it finishes sending the request. And if the server closes the connection without reading the whole request, the client may not see the response, depending on whether it fit into its receive buffer and on how it's written. If you just close the connection, the client might think it a network error and retry the request. So if you want to guarantee the client sees the rejection response, you have to read and discard the whole request. If you control the client as well as the server, and the server can reject the request based on its headers, the standard HTTP solution is to send Expect: 100-continue in the request, and then either 100 Continue or a 4xx rejection from the server. But if the server can only reject the request based on some prefix of the entity, HTTP provides no way to abort without closing the connection. You could cheat though: use chunked encoding for the request entity, and send an empty chunk ending the request entity as soon as you read the server's rejection headers. On Wednesday, January 28, 2015 at 6:33:47 PM UTC+2, Joe Edwards wrote: I have an application in which clients can upload large request entities to the server. In some situations the request will be rejected early (before the request body is totally consumed, as this may be hundreds of MB). Is there a standard way of handling this situation? Since the rejections may happen asynchronously, I can't guarantee how much (if any) of the request body has been read. As far as I can tell from RFC 7230 section 6.5 If the request is still in flight, we should respond early with a 'Connection: Close' (and the request stream will die as the connection closes). If the request has been totally received, we can respond normally and reuse the connection. Is there any easy way to determine when a response is being sent early? More generally, is it even legal to send a response before the entire request is received without closing the connection? I can't really tell from the spec, but if not it would make much more sense for akka-http to close the connection for us. Thanks, Joe -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: >>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" 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]. Visit this group at http://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout. -- Björn Antonsson Typesafe – Reactive Apps on the JVM twitter: @bantonsson -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: >>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" 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]. Visit this group at http://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
