akka http：服务器绑定未按预期运行

Question

我有以下代码：

val serverSource = Http().bind("localhost", 8080)
val connectionSink = Sink.foreach[IncomingConnection] {
    connection => println(s"Accepted incoming connection from ${connection.remoteAddress}")
  }
val serverBindingFuture = serverSource.to(connectionSink).run()
serverBindingFuture.onComplete {
    case Success(binding) => {
      println("Server binding successful")
      binding.terminate(10 seconds)
    }
    case Failure(ex) => println(s"Server binding failed $ex")
}

如代码片段所示，我将在 10 秒后终止服务器绑定。所以我希望如果我在此期限到期之前发送请求，我应该会打印消息 'Accepted incoming connection from...'。

但我发现我总是收到 'This site can’t be reached'，并且消息从未打印出来。

Answer 1

As the snippet tells, I am terminating the server binding after 10 seconds. So I expect that if I send the request before this period expires, I should get message 'Accepted incoming connection from...' printed.

您误解了 terminate 的语义。 duration 参数是一个 hard 关闭的最后期限，并不表示服务器将在此之前继续接受请求。

这里对您的代码进行了调整以证明这一点。

服务器一启动就打印Server binding successful并等待10秒再调用terminate
在调用 terminate 之前打印 Starting shutdown 并在 terminate 完成后立即打印 Finished shutdown

你应该看到：

curl 'http://localhost:8080/api 触发 println 直到 Starting shutdown 出现
Starting shutdown 和 Finished shutdown 之间的延迟可能很短（比 10 秒短得多）

val serverSource = Http().bind("localhost", 8080)
val connectionSink = Sink.foreach[IncomingConnection] {
  connection => println(s"Accepted incoming connection from ${connection.remoteAddress}")
}
val serverBindingFuture = serverSource.to(connectionSink).run()
serverBindingFuture.onComplete {
  case Success(binding) => {
    println("Server binding successful")
    system.scheduler.scheduleOnce(10 seconds) {
      println("Starting shutdown")
      binding.terminate(10 seconds).onComplete { termOutcome =>
        println(s"Finished shutdown $termOutcome")
      }
    }
  }
  case Failure(ex) => println(s"Server binding failed $ex")
}

akka http：服务器绑定未按预期运行

akka http: Server Binding not behaving as expected

akka-http