언더 타운. 다른 스레드와 비동기 응답

Question

Undertow를 사용하여 진정한 비동기 http 서버를 구축하는 방법을 알고 있습니다. 어떤 요청을 이미 처리하고있는 다른 스레드가 있으면 비동기 적으로 응답을 보내는 방법은 무엇입니까?
는이 같은 코드를 썼습니다 : 없음 데이터 및 로그에

Undertow server = Undertow.builder() 
      .addHttpListener(8080, "localhost") 
      .setHandler(exchange -> { 
       CompletableFuture.runAsync(() -> { 
        try { 
         Thread.sleep(100); 
        } catch (InterruptedException e) { 
         throw new RuntimeException(e); 
        } 
       }).thenAccept(string -> { 
        exchange.getResponseHeaders() 
          .put(Headers.CONTENT_TYPE, "text/plain"); 
        exchange.getResponseSender().send("Hello World"); 
        exchange.endExchange(); 
       }).exceptionally(throwable -> { 
        System.out.println(throwable.toString()); 
        return null; 
       }); 
      }).build(); 
    server.start(); 

그러나이 서버 응답 (200)

java.lang.IllegalStateException : UT000127 : 응답이 이미 발송되었습니다

다음과 같이 io.undertow.server.HttpServerExchange # dispatch (java.lang.Runnable) 메소드를 사용할 때 :

Undertow server = Undertow.builder() 
      .addHttpListener(8080, "localhost") 
      .setHandler(exchange -> { 

       exchange.dispatch(() -> { 

        CompletableFuture.runAsync(() -> { 
         try { 
          Thread.sleep(100); 
         } catch (InterruptedException e) { 
          throw new RuntimeException(e); 
         } 
        }).thenAccept(string -> { 
         exchange.getResponseHeaders() 
           .put(Headers.CONTENT_TYPE,"text/plain"); 
         exchange.getResponseSender().send("Hello World"); 
         exchange.endExchange(); 
        }).exceptionally(throwable -> { 
         System.out.println(throwable.toString()); 
         return null; 
        }); 

       }); 
      }).build(); 
    server.start(); 

물론 "Hello World"는 예상대로 응답하지만 서버는 모든 요청에 ​​대해 새 스레드를 만듭니다!

(jvisualvm 후 10 개 병렬 요청) 나 새로운 프로젝트를 생성

Answer 1

역류가이 방법을 지원하지은이를 해결하려면

https://github.com/hank-whu/undertow-async

package io.undertow.async.pingpong; 

import java.io.IOException; 
import java.util.concurrent.CompletableFuture; 

import io.undertow.async.handler.AsyncHttpHandler; 
import io.undertow.async.io.PooledByteBufferInputStream; 
import io.undertow.async.io.PooledByteBufferOutputStream; 
import io.undertow.connector.ByteBufferPool; 
import io.undertow.server.HttpServerExchange; 
import io.undertow.util.StatusCodes; 

public class PingPongAsyncHttpHandler extends AsyncHttpHandler { 

    @Override 
    protected void handleAsyncRequest(HttpServerExchange exchange, PooledByteBufferInputStream content) 
      throws Exception { 

     CompletableFuture// 
       .completedFuture(content)// init 
       .thenApplyAsync(this::readBytesAndClose)// read 
       .thenApplyAsync(bytes -> {// write 
        ByteBufferPool byteBufferPool = exchange.getConnection().getByteBufferPool(); 
        PooledByteBufferOutputStream output = new PooledByteBufferOutputStream(byteBufferPool); 
        write(output, bytes); 
        return output; 
       })// 
       .thenAcceptAsync(output -> send(exchange, StatusCodes.OK, output)); 
    } 

    private byte[] readBytesAndClose(PooledByteBufferInputStream content) { 
     try { 
      byte[] bytes = new byte[content.available()]; 
      content.read(bytes); 
      return bytes; 
     } catch (IOException e) { 
      throw new RuntimeException(e); 
     } finally { 
      try {// must close it 
       content.close(); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 
     } 
    } 

    private void write(PooledByteBufferOutputStream output, byte[] bytes) { 
     try { 
      output.write("asycn response: "); 
      output.write(bytes); 
     } catch (IOException e) { 
      throw new RuntimeException(e); 
     } 
    } 

}