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

[Stuart Douglas]

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(Http2Channel.java:827)
> at
> io.undertow.client.http2.Http2ClientConnection.sendRequest(Http2ClientConnection.java:195)
> at
> com.networknt.apic.handler.DataGetHandler.handleRequest(DataGetHandler.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(HttpClientConnection.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().getAttachment(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().getMapper().writeValueAsString(list));
>> >     }
>> > }
>> >
>> >
>> > _______________________________________________
>> > undertow-dev mailing list
>> > undertow-dev at lists.jboss.org
>> > https://lists.jboss.org/mailman/listinfo/undertow-dev
>
>