Asynchronous gRPC未来回调获取异常：StatusRuntimeException:已取消

当我使用future&callback调用grpc服务器句柄进程中的另一个grpc服务时，出现了如上所述的异常

我的代码如下：

io.grpc.StatusRuntimeException: CANCELLED
    at io.grpc.Status.asRuntimeException(Status.java:539)
    at io.grpc.stub.ClientCalls$UnaryStreamToFuture.onClose(ClientCalls.java:439)
    at io.grpc.internal.ClientCallImpl.closeObserver(ClientCallImpl.java:422)
    at io.grpc.internal.ClientCallImpl.access$100(ClientCallImpl.java:74)
    at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.close(ClientCallImpl.java:508)
    at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.access$700(ClientCallImpl.java:425)
    at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl$1StreamClosed.runInContext(ClientCallImpl.java:540)
    at io.grpc.internal.ContextRunnable.run(ContextRunnable.java:52)
    at io.grpc.internal.SerializeReentrantCallsDirectExecutor.execute(SerializeReentrantCallsDirectExecutor.java:64)
    at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.closed(ClientCallImpl.java:544)
    at io.grpc.internal.AbstractClientStream2$TransportState.closeListener(AbstractClientStream2.java:307)
    at io.grpc.internal.AbstractClientStream2$TransportState.transportReportStatus(AbstractClientStream2.java:287)
    at io.grpc.netty.NettyClientHandler.cancelStream(NettyClientHandler.java:455)
    at io.grpc.netty.NettyClientHandler.write(NettyClientHandler.java:231)
    at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:739)
    at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:731)
    at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:817)
    at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:724)
    at io.netty.channel.DefaultChannelPipeline.write(DefaultChannelPipeline.java:1022)
    at io.netty.channel.AbstractChannel.write(AbstractChannel.java:291)
    at io.grpc.netty.WriteQueue.flush(WriteQueue.java:124)
    at io.grpc.netty.WriteQueue.access$000(WriteQueue.java:46)
    at io.grpc.netty.WriteQueue$1.run(WriteQueue.java:58)
    at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
    at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:403)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:445)
    at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:858)
    at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:144)
    at java.lang.Thread.run(Thread.java:745)

handle（）{
....
***FutureClient FutureClient=。。。
ListenableFuture=futureClient.call（…）；
Futures.addCallback（future，newfuturecallback（）{…}）；
...
}

进程句柄（）完成时，访问被取消

---

如何解决此问题？

服务器传出的RPC通过

io.grpc.Context

隐式绑定到触发它们的传入请求。如果正在执行的RPC即使在传入RPC完成后仍继续进行，则应使用

context.fork（）

：

---

Context.run（Runnable）

也是直接使用附加/分离的一种方便的替代方法。

当出现客户端错误或应用程序代码（即您的代码）取消时，会发生取消。你确定你没有取消某个地方的未来吗？这正是我想要的！我希望在文件中也能清楚地说明这一点。

handle(){

....

***FutureClient futureClient = ...
ListenableFuture<***> future = futureClient.call(...);
Futures.addCallback(future, new FutureCallback<>() {...});

...

}

Context forked = Context.current().fork();
Context old = forked.attach();
try {
  // RPCs at this point can continue after the incoming RPC completes
  futureClient.call(...);
} finally {
  forked.detach(old);
}