Thomas, There is no configuration to avoid this behaviour. If jetty sees and exception in the application it will send the 400 and close the connection.
However, as Simone says, your application can be setup to avoid this situation by catching the exception and consuming any input. You can do this in a filter that catches Throwable, it can then check the request input stream (and/or reader) for unconsumed input and read & discard to end of file. If the response is not committed, it can then send a 400 or any other response that you like. Just remember that this may make your application somewhat vulnerable to DOS attacks as it will be easy to hold a thread in that filter slowly consuming data. I would suggest imposing a total time and total data limit on the input consumption. Note that for normal unconsumed input, jetty 9.4 does make some attempt to consume it... but if the reading of that data would block, it gives up and closes the connection, as there is no point blocking for data that will be discarded. regards On Wed, 26 Sep 2018 at 07:35, Thomas Becker <twbec...@gmail.com> wrote: > Thanks so much again for your response, this is great information. What > you say makes sense, but I now see I failed to mention the most critical > part of this problem. Which is that the client never actually sees the 400 > response we are sending from Jetty. When varnish sees the RST, it considers > the backend request failed and returns 503 Service Unavailable to the > client, effectively swallowing our application’s response. We can pursue a > solution to this on the Varnish side, but in the interim I’m guessing there > is no way to configure this behavior in Jetty? > > > > On Sep 25, 2018, at 4:28 PM, Simone Bordet <sbor...@webtide.com> wrote: > > Hi, > > On Tue, Sep 25, 2018 at 8:34 PM Tommy Becker <twbec...@gmail.com> wrote: > > > Update: we setup an environment with the old Jetty 9.2 code and this does > not occur. 9.2 does not send the FIN in #5 above, and seems happy to > receive the rest of the content, despite having sent a response already. > > On Tue, Sep 25, 2018 at 10:01 AM Tommy Becker <twbec...@gmail.com> wrote: > > > Thanks for your response. I managed to snag a tcp dump of what's going on > in this scenario. From what I can see the sequence of events is the > following. Recall that our Jetty server is fronted by a Varnish cache. > > 1) Varnish sends the headers and initial part of the content for a large > POST. > 2) On the Jetty server, we use a streaming parser and begin validating the > content. > 3) We detect a problem with the content and throw an exception that > results in a 400 Bad Request to the client (via JAX-RS exception mapper) > 4) An ACK is sent for the segment containing the 400 error. > 5) The Jetty server sends a FIN. > 6) An ACK is sent for the FIN > 7) Varnish sends another segment that continues the content from #1. > 8) The Jetty server sends a RST. > > In the server logs, we see an Early EOF from our JAX-RS resource that is > parsing the content. This all seems pretty ok from the Jetty side, and it > certainly seems like Varnish is misbehaving here (I'm thinking it may be > this bug https://github.com/varnishcache/varnish-cache/issues/2332). But > I'm still unclear as to why this started after our upgrade from Jetty 9.2 > -> 9.4. Any thoughts? > > > This is normal. > In Jetty 9.4 we are more aggressive in closing the connection because > we don't want to be at the mercy of a possible nasty client sending us > GiB of data when we know the application does not want to handle them. > Varnish behavior is correct too: it sees the FIN from Jetty but does > not know that Jetty does not want to read until it tries to send more > content and gets a RST. > At that point, it should relay the RST (or FIN) back to the client. > > So you have 2 choices: you catch the exception during your validation, > and finish to read (and discard) the content in the application; or > you ignore the early EOFs in the logs. > I don't think that those early EOFs are logged above DEBUG level, is > that correct? > > -- > Simone Bordet > ---- > http://cometd.org > http://webtide.com > Developer advice, training, services and support > from the Jetty & CometD experts. > _______________________________________________ > jetty-users mailing list > jetty-users@eclipse.org > To change your delivery options, retrieve your password, or unsubscribe > from this list, visit > https://dev.eclipse.org/mailman/listinfo/jetty-users > > > _______________________________________________ > jetty-users mailing list > jetty-users@eclipse.org > To change your delivery options, retrieve your password, or unsubscribe > from this list, visit > https://dev.eclipse.org/mailman/listinfo/jetty-users -- Greg Wilkins <gr...@webtide.com> CTO http://webtide.com
_______________________________________________ jetty-users mailing list jetty-users@eclipse.org To change your delivery options, retrieve your password, or unsubscribe from this list, visit https://dev.eclipse.org/mailman/listinfo/jetty-users
