Akka REST service + dispatch

Question

I followed the example here. It works, fine. But now I need to perform some business logic in case get:Get =>

Required business logic includes using dispatch library. In a nutshell, I do a request to some page, get the data, wrap it in some class, and return it.

My receiving case looks like this:

case get:Get => {
  get.response.setContentType(MediaType.APPLICATION_JSON)
  val response = Sender.doLogin
  val battery = (response.batteryRemaining / response.batteryCapacity) * 100
  val soc = (response.pluginState + ", " + response.chargingStatus).replaceAll("_", " ")
  val jsonResult = pretty(render(("battery" -> battery) ~ ("soc" -> soc)))
  get OK jsonResult
  // get OK "works"
}

This does not work:

ERROR [akka:event-driven:dispatcher:event:handler-5] akka.event.slf4j.Slf4jEventHandler - 
    [akka.http.Servlet30ContextMethodFactory$$anon$2]
    [org.eclipse.jetty.io.EofException]
    [org.eclipse.jetty.io.UncheckedIOException: org.eclipse.jetty.io.EofException
    at org.eclipse.jetty.io.UncheckedPrintWriter.setError(UncheckedPrintWriter.java:107)
    at org.eclipse.jetty.io.UncheckedPrintWriter.write(UncheckedPrintWriter.java:280)
    at org.eclipse.jetty.io.UncheckedPrintWriter.write(UncheckedPrintWriter.java:295)
    at akka.http.RequestMethod$$anonfun$complete$1.apply(Mist.scala:346)
    at akka.http.RequestMethod$$anonfun$complete$1.apply(Mist.scala:343)
    at akka.http.RequestMethod$class.rawComplete(Mist.scala:357)
    at akka.http.Get.rawComplete(Mist.scala:407)
    at akka.http.RequestMethod$class.complete(Mist.scala:343)
    at akka.http.Get.complete(Mist.scala:407)
    at akka.http.RequestMethod$class.complete(Mist.scala:340)
    at akka.http.Get.complete(Mist.scala:407)
    at akka.http.RequestMethod$class.OK(Mist.scala:388)
    at akka.http.Get.OK(Mist.scala:407)
    at com.thenewmotion.caronline.services.rest.BatteryStatusService$$anonfun$receive$1.apply(BatteryStatusService.scala:36)
    at com.thenewmotion.caronline.services.rest.BatteryStatusService$$anonfun$receive$1.apply(BatteryStatusService.scala:28)
    at akka.actor.Actor$class.apply(Actor.scala:563)
    at com.thenewmotion.caronline.services.rest.BatteryStatusService.apply(BatteryStatusService.scala:27)
    at akka.actor.LocalActorRef.invoke(ActorRef.scala:890)
    at akka.dispatch.MessageInvocation.invoke(MessageHandling.scala:25)
    at akka.dispatch.ExecutableMailbox$class.processMailbox(ExecutorBasedEventDrivenDispatcher.scala:214)
    at akka.dispatch.ExecutorBasedEventDrivenDispatcher$$anon$4.processMailbox(ExecutorBasedEventDrivenDispatcher.scala:120)
    at akka.dispatch.ExecutableMailbox$class.run(ExecutorBasedEventDrivenDispatcher.scala:186)
    at akka.dispatch.ExecutorBasedEventDrivenDispatcher$$anon$4.run(ExecutorBasedEventDrivenDispatcher.scala:120)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:662)
    at akka.dispatch.MonitorableThread.run(ThreadPoolBuilder.scala:181)
Caused by: org.eclipse.jetty.io.EofException
    at org.eclipse.jetty.server.HttpOutput.write(HttpOutput.java:150)
    at org.eclipse.jetty.server.HttpOutput.write(HttpOutput.java:97)
    at java.io.ByteArrayOutputStream.writeTo(ByteArrayOutputStream.java:109)
    at org.eclipse.jetty.server.HttpWriter.write(HttpWriter.java:283)
    at org.eclipse.jetty.server.HttpWriter.write(HttpWriter.java:107)
    at org.eclipse.jetty.io.UncheckedPrintWriter.write(UncheckedPrintWriter.java:271)
    ... 25 more
]

It also seems, that it starts making the request (with dispatch library) after it responds with HTTP 200 OK.

What could be the problem here?

For whatever it is worth, your use case seems to be exactly the kind of stuff that [Blue Eyes](https://github.com/jdegoes/blueeyes) was made for. — Daniel C. Sobral, Aug 26 '11 at 13:43

score 3 · Accepted Answer · answered Aug 26 '11 at 13:34

3

Try turning off connection-close: https://github.com/jboner/akka/blob/master/config/akka-reference.conf#L262

answered Aug 26 '11 at 13:34

Viktor Klang

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Did not help. I also verified, that effectively any dispatch request from the receive body results in this exception. – George Aug 26 '11 at 14:15
That's interesting. When I leave it without requests for about 10 minutes, it works once, and then stops working again. – George Aug 26 '11 at 15:01
What happens if you set the get.response.setContentType(MediaType.APPLICATION_JSON) just prior to the get OK ? – Viktor Klang Aug 26 '11 at 15:22
1

Same thing. But I was able to make it work by increasing some timeouts in `akka.conf`. Namely, `actor.timeout` and `http.timeout`. And I also added a `get.timeout(10000)` to the beginning of the `case` expression. – George Aug 26 '11 at 15:53

Akka REST service + dispatch

1 Answers1