Play Framework/Scala example source code file (WebSocketHandshake.scala)

This example Play Framework source code file (WebSocketHandshake.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Play Framework (and Scala) source code examples by using tags.

All credit for the original source code belongs to Play Framework; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Play Framework tags/keywords

api, channelhandlercontext, concurrent, core, httprequest, lib, library, long, nosuchelementexception, play, play framework, unit, websocket, websockethandshake, websocketserverhandshakerfactory

The WebSocketHandshake.scala Play Framework example source code

/*
 * Copyright (C) 2009-2013 Typesafe Inc. <http://www.typesafe.com>
 */
package play.core.server.websocket

import org.jboss.netty.handler.codec.http.HttpRequest;
import org.jboss.netty.buffer._
import org.jboss.netty.channel._
import org.jboss.netty.bootstrap._
import org.jboss.netty.channel.Channels._
import org.jboss.netty.handler.codec.http._
import org.jboss.netty.channel.socket.nio._
import org.jboss.netty.handler.stream._
import org.jboss.netty.handler.codec.http.HttpHeaders._
import org.jboss.netty.handler.codec.http.HttpHeaders.Names._
import org.jboss.netty.handler.codec.http.HttpHeaders.Values._
import org.jboss.netty.handler.codec.http.websocketx._

import org.jboss.netty.channel.group._
import java.util.concurrent._

import play.core._
import play.api._
import play.api.mvc._
import play.api.libs.iteratee._
import play.api.libs.concurrent._
import org.apache.commons.codec.binary.Base64

import java.nio.charset.Charset
import java.security.MessageDigest

object WebSocketHandshake {
  protected def getWebSocketLocation(request: HttpRequest) = "ws://" + request.getHeader(HttpHeaders.Names.HOST) + request.getUri()

  def shake(ctx: ChannelHandlerContext, req: HttpRequest, bufferLimit: Long): Unit = {
    val factory = new WebSocketServerHandshakerFactory(getWebSocketLocation(req),
      "*", /* wildcard to accept all subprotocols */
      true /* allowExtensions */ ,
      bufferLimit
    )

    val shaker = factory.newHandshaker(req)

    // HACK ALERT: the netty websocket handshaker wants to remove
    // an HttpChunkAggregator and throws an exception when it
    // isn't in the pipeline. We just put it in here so it can be
    // taken back out, as a workaround. Needs better fix.
    val pipeline = ctx.getChannel.getPipeline
    pipeline.addLast("hack-remove-this-chunk-aggregator", new HttpChunkAggregator(Int.MaxValue))

    shaker.handshake(ctx.getChannel, req)

    // be sure the HttpChunkAggregator goes away, if handshake
    // didn't remove it as expected.
    try {
      pipeline.remove(classOf[HttpChunkAggregator])
    } catch {
      case ex: NoSuchElementException =>
      // this is what we're expecting, since handshake removed it
    }
  }

}