First pass at providing a convenient API for handling websockets

4 files changed, 128 insertions, 3 deletions

diff --git a/cask/src/cask/endpoints/WebSocketEndpoint.scala b/cask/src/cask/endpoints/WebSocketEndpoint.scala
index 842d508..6728581 100644
--- a/cask/src/cask/endpoints/WebSocketEndpoint.scala
+++ b/cask/src/cask/endpoints/WebSocketEndpoint.scala
@@ -1,9 +1,15 @@
 package cask.endpoints
 
-import cask.internal.Router
+import java.nio.ByteBuffer
+
+import cask.internal.{BatchActor, Router}
 import cask.model.Request
 import io.undertow.websockets.WebSocketConnectionCallback
-import collection.JavaConverters._
+import io.undertow.websockets.core.{AbstractReceiveListener, BufferedBinaryMessage, BufferedTextMessage, CloseMessage, WebSocketChannel, WebSockets}
+import io.undertow.websockets.spi.WebSocketHttpExchange
+
+import scala.concurrent.ExecutionContext
+
 sealed trait WebsocketResult
 object WebsocketResult{
   implicit class Response[T](value0: cask.model.Response[T])
@@ -24,3 +30,78 @@ class websocket(val path: String, override val subpath: Boolean = false)
 
   def wrapPathSegment(s: String): Seq[String] = Seq(s)
 }
+
+case class WsHandler(f: WsChannelActor => BatchActor[WsActor.Event])(implicit ec: ExecutionContext)
+extends WebsocketResult with WebSocketConnectionCallback {
+   def onConnect(exchange: WebSocketHttpExchange, channel: WebSocketChannel): Unit = {
+     val actor = f(new WsChannelActor(channel))
+     channel.getReceiveSetter.set(
+       new AbstractReceiveListener() {
+         override def onFullTextMessage(channel: WebSocketChannel, message: BufferedTextMessage) = {
+           actor.send(WsActor.Text(message.getData))
+         }
+
+         override def onFullBinaryMessage(channel: WebSocketChannel, message: BufferedBinaryMessage): Unit = {
+           actor.send(WsActor.Binary(
+             WebSockets.mergeBuffers(message.getData.getResource:_*).array()
+           ))
+         }
+
+         override def onFullPingMessage(channel: WebSocketChannel, message: BufferedBinaryMessage): Unit = {
+           actor.send(WsActor.Ping(
+             WebSockets.mergeBuffers(message.getData.getResource:_*).array()
+           ))
+         }
+         override def onFullPongMessage(channel: WebSocketChannel, message: BufferedBinaryMessage): Unit = {
+           actor.send(WsActor.Pong(
+             WebSockets.mergeBuffers(message.getData.getResource:_*).array()
+           ))
+         }
+
+         override def onCloseMessage(cm: CloseMessage, channel: WebSocketChannel) = {
+           actor.send(WsActor.Close(cm.getCode, cm.getReason))
+         }
+       }
+     )
+    channel.resumeReceives()
+  }
+}
+
+class WsChannelActor(channel: WebSocketChannel)(implicit ec: ExecutionContext)
+extends BatchActor[WsActor.Event]{
+  def run(items: Seq[WsActor.Event]): Unit = items.foreach{
+    case WsActor.Text(value) => WebSockets.sendTextBlocking(value, channel)
+    case WsActor.Binary(value) => WebSockets.sendBinaryBlocking(ByteBuffer.wrap(value), channel)
+    case WsActor.Ping(value) => WebSockets.sendPingBlocking(ByteBuffer.wrap(value), channel)
+    case WsActor.Pong(value) => WebSockets.sendPingBlocking(ByteBuffer.wrap(value), channel)
+    case WsActor.Close(code, reason) => WebSockets.sendCloseBlocking(code, reason, channel)
+  }
+}
+
+case class WsActor(handle: PartialFunction[WsActor.Event, Unit])
+                  (implicit ec: ExecutionContext)
+extends BatchActor[WsActor.Event]{
+  def run(items: Seq[WsActor.Event]): Unit = {
+    items.foreach(handle.applyOrElse(_, (x: WsActor.Event) => ()))
+  }
+}
+
+object WsActor{
+  trait Event
+  case class Text(value: String) extends Event
+  case class Binary(value: Array[Byte]) extends Event
+  case class Ping(value: Array[Byte] = Array.empty[Byte]) extends Event
+  case class Pong(value: Array[Byte] = Array.empty[Byte]) extends Event
+  case class Close(code: Int = Close.NormalClosure, reason: String = "") extends Event
+  object Close{
+    val NormalClosure = CloseMessage.NORMAL_CLOSURE
+    val GoingAway = CloseMessage.GOING_AWAY
+    val WrongCode = CloseMessage.WRONG_CODE
+    val ProtocolError = CloseMessage.PROTOCOL_ERROR
+    val MsgContainsInvalidData = CloseMessage.MSG_CONTAINS_INVALID_DATA
+    val MsgViolatesPolicy = CloseMessage.MSG_VIOLATES_POLICY
+    val MsgTooBig = CloseMessage.MSG_TOO_BIG
+    val MissingExtensions = CloseMessage.MISSING_EXTENSIONS
+    val UnexpectedError = CloseMessage.UNEXPECTED_ERROR
+  }
+}
diff --git a/cask/src/cask/internal/BatchActor.scala b/cask/src/cask/internal/BatchActor.scala
new file mode 100644
index 0000000..1566a18
--- /dev/null
+++ b/cask/src/cask/internal/BatchActor.scala
@@ -0,0 +1,37 @@
+package cask.internal
+
+import scala.collection.mutable
+import scala.concurrent.ExecutionContext
+
+/**
+ * A simple asynchrous actor, allowing safe concurrent asynchronous processing
+ * of queued items. `run` handles items in batches, to allow for batch
+ * processing optimizations to be used where relevant.
+ */
+abstract class BatchActor[T]()(implicit ec: ExecutionContext) {
+  def run(items: Seq[T]): Unit
+
+  private val queue = new mutable.Queue[T]()
+  private var scheduled = false
+  def send(t: => T): Unit = synchronized{
+    queue.enqueue(t)
+    if (!scheduled){
+      scheduled = true
+      ec.execute(() => runWithItems())
+    }
+  }
+
+  def runWithItems(): Unit = {
+    val items = synchronized(queue.dequeueAll(_ => true))
+    try run(items)
+    catch{case e: Throwable => e.printStackTrace()}
+    synchronized{
+      if (queue.nonEmpty) ec.execute(() => runWithItems())
+      else{
+        assert(scheduled)
+        scheduled = false
+      }
+    }
+
+  }
+}
diff --git a/cask/src/cask/main/Main.scala b/cask/src/cask/main/Main.scala
index 32e6517..a138e8a 100644
--- a/cask/src/cask/main/Main.scala
+++ b/cask/src/cask/main/Main.scala
@@ -1,6 +1,6 @@
 package cask.main
 
-import cask.endpoints.WebsocketResult
+import cask.endpoints.{WebsocketResult, WsHandler}
 import cask.model._
 import cask.internal.Router.EntryPoint
 import cask.internal.{DispatchTrie, Router, Util}
@@ -73,6 +73,8 @@ abstract class BaseMain{
         val (effectiveMethod, runner) = if (exchange.getRequestHeaders.getFirst("Upgrade") == "websocket") {
           "websocket" -> ((r: Any) =>
             r.asInstanceOf[WebsocketResult] match{
+              case l: WsHandler =>
+                io.undertow.Handlers.websocket(l).handleRequest(exchange)
               case l: WebsocketResult.Listener =>
                 io.undertow.Handlers.websocket(l.value).handleRequest(exchange)
               case r: WebsocketResult.Response[_] =>
diff --git a/cask/src/cask/package.scala b/cask/src/cask/package.scala
index d17cfe6..f55d33d 100644
--- a/cask/src/cask/package.scala
+++ b/cask/src/cask/package.scala
@@ -40,4 +40,9 @@ package object cask {
   type RawDecorator = main.RawDecorator
   type HttpEndpoint[InnerReturned, Input] = main.HttpEndpoint[InnerReturned, Input]
 
+  type WsHandler = cask.endpoints.WsHandler
+  val WsHandler = cask.endpoints.WsHandler
+  type WsActor = cask.endpoints.WsActor
+  val WsActor = cask.endpoints.WsActor
+  type WsChannelActor = cask.endpoints.WsChannelActor
 }