[undertow-dev] Using UndertowClient from one server to call another server

[Steve Hu]

Hi Stuart,

I have created two servers with one calls another with h2c-prior to
reproduce the issue. There is a README.md in the root folder with
instructions.

https://github.com/stevehu/server2server

Thanks,

Steve

On Mon, Aug 28, 2017 at 11:01 PM, Stuart Douglas <sdouglas at redhat.com>
wrote:

> That would be great. This is tested in the test suite so I am not sure why
> it is not working for you.
>
> Stuart
>
> On 29 Aug. 2017 12:59 pm, "Steve Hu" <stevehu at gmail.com> wrote:
>
> Yes. It is another Undertow server with HTTP 2.0 enabled. I can build a
> repo with two servers to reproduce the issue if it is necessary.
>
> Thanks,
>
> Steve
>
> On Mon, Aug 28, 2017 at 10:43 PM, Stuart Douglas <sdouglas at redhat.com>
> wrote:
>
>> What is the endpoint that you are trying to connect to? Is it another
>> Undertow server?
>>
>> Stuart
>>
>> On Tue, Aug 29, 2017 at 12:17 PM, Steve Hu <stevehu at gmail.com> wrote:
>> > Hi Stuart,
>> >
>> > Thanks for the quick reply. I have opened an issue
>> > https://issues.jboss.org/browse/UNDERTOW-1170
>> >
>> > Also, I have tried your workaround with h2c-prior:// but got the
>> following
>> > error in the callback.
>> >
>> > java.nio.channels.ClosedChannelException
>> > at
>> > io.undertow.protocols.http2.Http2Channel.createStream(Http2C
>> hannel.java:827)
>> > at
>> > io.undertow.client.http2.Http2ClientConnection.sendRequest(H
>> ttp2ClientConnection.java:195)
>> > at
>> > com.networknt.apic.handler.DataGetHandler.handleRequest(Data
>> GetHandler.java:57)
>> >
>> >
>> > On Mon, Aug 28, 2017 at 9:50 PM, Stuart Douglas <sdouglas at redhat.com>
>> wrote:
>> >>
>> >> This looks like a bug in the client with regards to how it handles
>> >> HTTP upgrade. If the second request is added before the initial
>> >> upgrade request is fully processed you can get this error.
>> >>
>> >> If you file a JIRA I will look into it. For now a possible workaround
>> >> would be to use prior knowledge rather than upgrade (by using a URL of
>> >> the form h2c-prior://target:p8080/whatever).
>> >>
>> >> Stuart
>> >>
>> >> On Tue, Aug 29, 2017 at 11:25 AM, Steve Hu <stevehu at gmail.com> wrote:
>> >> > Hi,
>> >> >
>> >> > I am trying to use UndertowClient to call another service in the
>> current
>> >> > service handleRequest using HTTP 2.0. If I have concurrent requests
>> to
>> >> > the
>> >> > current service, then I will get the following error.
>> >> >
>> >> > java.io.IOException: UT001033: Invalid connection state
>> >> > at
>> >> >
>> >> > io.undertow.client.http.HttpClientConnection.sendRequest(Htt
>> pClientConnection.java:336)
>> >> >
>> >> > Since HTTP 2.0 connection is multiplex, so I use instance variables
>> for
>> >> > UndertowClient instance and ClientConnection instance and don't close
>> >> > the
>> >> > connection for each call.
>> >> >
>> >> > My question is how many requests can go through the same connection?
>> Is
>> >> > the
>> >> > Invalid connection state caused by too many requests in the same
>> >> > connection?
>> >> > If yes, I can use a connection pool just like the HTTP 1.1. Also, is
>> it
>> >> > possible that the server will close the connection if it is idle for
>> a
>> >> > period of time?
>> >> >
>> >> > Here is the handler code for reference.
>> >> >
>> >> > public class DataGetHandler implements HttpHandler {
>> >> >     UndertowClient client = UndertowClient.getInstance();
>> >> >     ClientConnection connection;
>> >> >
>> >> >     @Override
>> >> >     public void handleRequest(HttpServerExchange exchange) throws
>> >> > Exception
>> >> > {
>> >> >         List<String> list = new ArrayList<>();
>> >> >         final CountDownLatch latch = new CountDownLatch(1);
>> >> >         if(connection == null) {
>> >> >             try {
>> >> >                 connection = client.connect(new URI(apidHost),
>> >> > Http2Client.WORKER, Http2Client.SSL, Http2Client.POOL, enableHttp2 ?
>> >> > OptionMap.create(UndertowOptions.ENABLE_HTTP2, true):
>> >> > OptionMap.EMPTY).get();
>> >> >             } catch (Exception e) {
>> >> >                 logger.error("Exeption:", e);
>> >> >                 throw new ClientException(e);
>> >> >             }
>> >> >         }
>> >> >         final AtomicReference<ClientResponse> reference = new
>> >> > AtomicReference<>();
>> >> >         try {
>> >> >             ClientRequest request = new
>> >> > ClientRequest().setMethod(Methods.GET).setPath(apidPath);
>> >> >             connection.sendRequest(request,
>> >> > client.createClientCallback(reference, latch));
>> >> >             latch.await();
>> >> >             int statusCode = reference.get().getResponseCode();
>> >> >             if(statusCode >= 300){
>> >> >                 throw new Exception("Failed to call API D: " +
>> >> > statusCode);
>> >> >             }
>> >> >             List<String> apidList =
>> >> >
>> >> > Config.getInstance().getMapper().readValue(reference.get().g
>> etAttachment(Http2Client.RESPONSE_BODY),
>> >> >                     new TypeReference<List<String>>(){});
>> >> >             list.addAll(apidList);
>> >> >         } catch (Exception e) {
>> >> >             logger.error("Exception:", e);
>> >> >             throw new ClientException(e);
>> >> >         }
>> >> >         list.add("API C: Message 1");
>> >> >         list.add("API C: Message 2");
>> >> >
>> >> >
>> >> > exchange.getResponseSender().send(Config.getInstance().getMa
>> pper().writeValueAsString(list));
>> >> >     }
>> >> > }
>> >> >
>> >> >
>> >> > _______________________________________________
>> >> > undertow-dev mailing list
>> >> > undertow-dev at lists.jboss.org
>> >> > https://lists.jboss.org/mailman/listinfo/undertow-dev
>> >
>> >
>>
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/undertow-dev/attachments/20170829/8b97a975/attachment.html