Question

如何在播放ws客户端中处理超时异常？当我指定RequestTimeout和流程流时，即使存在异常，CompletionStage也会成功完成。

请参阅下面的示例。

代码（取自here）：

// Make the request, which should timeout
        CompletionStage<StreamedResponse> futureResponse = ws.url("https://download.docker.com/mac/stable/Docker.dmg")
                .setMethod("GET").setRequestTimeout(1000)
                .stream();

        CompletionStage<Long> bytesReturned = futureResponse.thenCompose(res -> {
            Source<ByteString, ?> responseBody = res.getBody();

            // Count the number of bytes returned
            Sink<ByteString, CompletionStage<Long>> bytesSum = Sink.fold(0L, (total, bytes) -> 
            { 
                long len = bytes.toArray().length;
                return total + len;
            });

            return responseBody.runWith(bytesSum, materializer);
        }).handle((res, err) -> {
            LOGGER.info("Res = {}, err = {}", res, err);
            return 200L;
        }).exceptionally(ex -> {
            LOGGER.error("See exception");
            return 100L;
        });
        try {
            bytesReturned.toCompletableFuture().get();
            LOGGER.info("Got response");
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (ExecutionException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        LOGGER.error("Step completed");

我在日志中看到抛出java.util.concurrent.TimeoutException和o.a.netty.timeout.TimeoutTimerTask，但futureResponse成功完成。有没有办法捕捉到这个错误？

我的问题是我试图通过控制器将该响应返回给用户，并且因为并非所有数据都已传输，因此只会挂起。

[debug] i.n.u.i.JavassistTypeParameterMatcherGenerator - Generated: io.netty.util.internal.__matchers__.org.asynchttpclient.HttpResponseBodyPartMatcher
[debug] o.a.netty.channel.DefaultChannelPool - Closed 0 connections out of 0 in 0 ms
[debug] o.a.netty.timeout.TimeoutTimerTask - Request timeout to download.docker.com/52.84.239.124:443 after 1000 ms for NettyResponseFuture{currentRetry=0,
    isDone=0,
    isCancelled=0,
    asyncHandler=play.api.libs.ws.ahc.Streamed$DefaultStreamedAsyncHandler@376665d1,
    nettyRequest=org.asynchttpclient.netty.request.NettyRequest@39a19d4d,
    future=java.util.concurrent.CompletableFuture@3d9e0ea1[Not completed],
    uri=https://download.docker.com/mac/stable/Docker.dmg,
    keepAlive=true,
    redirectCount=0,
    timeoutsHolder=org.asynchttpclient.netty.timeout.TimeoutsHolder@789c9776,
    inAuth=0,
    statusReceived=1,
    touch=1491606083196} after 1075 ms
[debug] o.a.netty.channel.ChannelManager - Closing Channel [id: 0x66ec6bbd, L:/10.155.124.116:52337 - R:download.docker.com/52.84.239.124:443] 
[debug] o.a.netty.request.NettyRequestSender - Aborting Future NettyResponseFuture{currentRetry=0,
    isDone=0,
    isCancelled=0,
    asyncHandler=play.api.libs.ws.ahc.Streamed$DefaultStreamedAsyncHandler@376665d1,
    nettyRequest=org.asynchttpclient.netty.request.NettyRequest@39a19d4d,
    future=java.util.concurrent.CompletableFuture@3d9e0ea1[Not completed],
    uri=https://download.docker.com/mac/stable/Docker.dmg,
    keepAlive=true,
    redirectCount=0,
    timeoutsHolder=org.asynchttpclient.netty.timeout.TimeoutsHolder@789c9776,
    inAuth=0,
    statusReceived=1,
    touch=1491606083196}

[debug] o.a.netty.request.NettyRequestSender - Request timeout to download.docker.com/52.84.239.124:443 after 1000 ms
java.util.concurrent.TimeoutException: Request timeout to download.docker.com/52.84.239.124:443 after 1000 ms
    at org.asynchttpclient.netty.timeout.TimeoutTimerTask.expire(TimeoutTimerTask.java:43)
    at org.asynchttpclient.netty.timeout.RequestTimeoutTimerTask.run(RequestTimeoutTimerTask.java:48)
    at io.netty.util.HashedWheelTimer$HashedWheelTimeout.expire(HashedWheelTimer.java:588)
    at io.netty.util.HashedWheelTimer$HashedWheelBucket.expireTimeouts(HashedWheelTimer.java:662)
    at io.netty.util.HashedWheelTimer$Worker.run(HashedWheelTimer.java:385)
    at java.lang.Thread.run(Thread.java:745)
[debug] o.a.netty.handler.HttpHandler - Channel Closed: [id: 0x66ec6bbd, L:/10.155.124.116:52337 ! R:download.docker.com/52.84.239.124:443] with attribute INSTANCE
[info] controllers.RedirectController - Res = 2556824, err = null
[info] controllers.RedirectController - Got response
[error] controllers.RedirectController - Step completed

Answer 1

即使我在Play 1.2中遇到超时异常，因为api需要很长时间才能发回回复。我能够手动设置超时，解决了我的问题。

WSRequest request = WS.url(your_url).timeout("600s");

Play Framework处理请求超时

1 个答案: