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is broken in IE */ @serializable case class RenderOut(xhtml: Box[NodeSeq], fixedXhtml: Box[NodeSeq], script: Box[JsCmd], destroyScript: Box[JsCmd], ignoreHtmlOnJs: Boolean) { def this(xhtml: NodeSeq) = this (Full(xhtml), Empty, Empty, Empty, false) def this(xhtml: NodeSeq, js: JsCmd) = this (Full(xhtml), Empty, Full(js), Empty, false) def this(xhtml: NodeSeq, js: JsCmd, destroy: JsCmd) = this (Full(xhtml), Empty, Full(js), Full(destroy), false) def ++(cmd: JsCmd) = RenderOut(xhtml, fixedXhtml, script.map(_ & cmd) or Full(cmd), destroyScript, ignoreHtmlOnJs) } @serializable private[http] object Never

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Lift Framework example source code file (CometActor.scala)

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Java - Lift Framework tags/keywords

any, box, box, cometmessage, empty, empty, full, jscmd, nodeseq, nodeseq, partialfunction, string, string, unit, util

The Lift Framework CometActor.scala source code

/*
 * Copyright 2007-2011 WorldWide Conferencing, LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.liftweb
package http

import net.liftweb.common._
import net.liftweb.actor._
import scala.collection.mutable.{ListBuffer}
import net.liftweb.util.Helpers._
import net.liftweb.util._
import net.liftweb.json._
import scala.xml.{NodeSeq, Text, Elem, Node, Group, Null, PrefixedAttribute, UnprefixedAttribute}
import scala.collection.immutable.TreeMap
import scala.collection.mutable.{HashSet, ListBuffer}
import net.liftweb.http.js._
import JsCmds._
import JE._
import java.util.concurrent.atomic.AtomicLong
import java.util.Locale

/**
 * An actor that monitors other actors that are linked with it. If a watched
 * actor terminates,this actor captures the Exit messag, executes failureFuncs
 * and resurects the actor.
 */
object ActorWatcher extends scala.actors.Actor with Loggable {
  import scala.actors.Actor._
  def act = loop {
    react {
      case scala.actors.Exit(actor: scala.actors.Actor, why: Throwable) =>
        failureFuncs.foreach(f => tryo(f(actor, why)))

      case _ =>
    }
  }

  private def startAgain(a: scala.actors.Actor, ignore: Throwable) {
    a.start
    a ! RelinkToActorWatcher
  }

  private def logActorFailure(actor: scala.actors.Actor, why: Throwable) {
    logger.warn("The ActorWatcher restarted " + actor + " because " + why, why)
  }

  /**
   * If there's something to do in addition to starting the actor up, pre-pend the
   * actor to this List
   */
  @volatile var failureFuncs: List[(scala.actors.Actor, Throwable) => Unit] = logActorFailure _ ::
          startAgain _ :: Nil

  this.trapExit = true
  this.start
}

/**
 * This is used as an indicator message for linked actors.
 *
 * @see ActorWatcher
 */
case object RelinkToActorWatcher

trait DeltaTrait {
  def toJs: JsCmd
}

trait CometState[DeltaType <: DeltaTrait,
MyType <: CometState[DeltaType, MyType]] {
  self: MyType =>

  def -(other: MyType): Seq[DeltaType]

  def render: NodeSeq
}

trait CometStateWithUpdate[UpdateType, DeltaType <: DeltaTrait,
MyType <: CometStateWithUpdate[UpdateType,
        DeltaType, MyType]]
        extends CometState[DeltaType, MyType]
{
  self: MyType =>
  def process(in: UpdateType): MyType
}

trait StatefulComet extends CometActor {
  type Delta <: DeltaTrait
  type State <: CometState[Delta, State]

  /**
   * Test the parameter to see if it's an updated state object
   */
  def testState(in: Any): Box[State]

  /**
   * Return the empty state object
   */
  def emptyState: State

  /**
   * The current state objects
   */
  protected var state: State = emptyState

  /**
   * If there's some ThreadLocal variable that needs to be setup up
   * before processing the state deltas, set it up here.
   */
  protected def setupLocalState[T](f: => T): T = f

  private[http] override val _lowPriority = {
    val pf: PartialFunction[Any, Unit] = {
      case v if testState(v).isDefined =>
        testState(v).foreach {
          ns =>
                  if (ns ne state) {
                    val diff = ns - state
                    state = ns
                    partialUpdate(setupLocalState {diff.map(_.toJs).foldLeft(Noop)(_ & _)})
                  }
        }
    }

    pf orElse super._lowPriority
  }

  /**
   * The Render method
   */
  def render = state.render
}

object CurrentCometActor extends ThreadGlobal[LiftCometActor]

object AddAListener {
  def apply(who: SimpleActor[Any]) = new AddAListener(who, { case _ => true } )
}

/**
 * This is a message class for use with ListenerManager and CometListener
 * instances. The use of the shouldUpdate function is deprecated, and
 * should instead be handled by the message processing partial functions
 * on the CometListner instances themselves.
 *
 * @see CometListener
 * @see ListenerManager
 */
case class AddAListener(who: SimpleActor[Any], shouldUpdate: PartialFunction[Any, Boolean])

/**
 * This is a message class for use with ListenerManager and CometListener
 * instances.
 *
 * @see CometListener
 * @see ListenerManager
 */
case class RemoveAListener(who: SimpleActor[Any])


object ListenerManager {
  type ActorTest = (SimpleActor[Any], PartialFunction[Any, Boolean])
}


/**
 * This trait manages a set of Actors in a publish/subscribe pattern. When you extend your Actor with
 * this trait, you automatically get handling for sending messages out to all subscribed Actors. Simply
 * override the high-, medium-, or lowPriority handlers to do your message processing. When you want to update
 * all subscribers, just call the updateListeners method. The createUpdate method is used to generate
 * the message that you want sent to all subscribers.
 *
 * Note that the AddAListener and RemoveAListener messages (for subscription control) are processed
 * after any highPriority or mediumPriority messages are processed, so take care to avoid overly
 * broad matches in those handlers that might consume internal messages.
 *
 * For example, you could write a simple service to provide clock ticks using the following code:
 *
 * <pre name="code" class="scala">
 * case object Tick
 * 
 * object Ticker extends ListenerManager {
 *   import net.liftweb.util.ActorPing
 * 
 *   // Set up the initial tick
 *   ActorPing.schedule(this, Tick, 1000L)
 *
 *   // This is a placeholder, since we're only interested
 *   // in Ticks
 *   def createUpdate = "Registered"
 * 
 *   override def mediumPriority = {
 *     case Tick => {
 *       updateListeneres(Tick)
 *       ActorPing.schedule(this, Tick, 1000L)
 *     }
 *   }
 * }
 * </pre>
 *
 * A client CometActor could look like:
 *
 * <pre name="code" class="scala">
 * class CometClock extends CometListener {
 *   val registerWith = Ticker
 *
 *   ... handling code ...
 * }
 * </pre>
 *
 * @see CometListener
 *   
 */
trait ListenerManager {
  self: SimpleActor[Any] =>

  import ListenerManager._

  /**
   * This is the list of all registered actors
   */
  private var listeners: List[ActorTest] = Nil

  protected def messageHandler: PartialFunction[Any, Unit] =
    highPriority orElse mediumPriority orElse
            listenerService orElse lowPriority

  protected def listenerService: PartialFunction[Any, Unit] =
    {
      case AddAListener(who, shouldUpdate) =>
        val pair = (who, shouldUpdate)
        listeners ::= pair
        updateIfPassesTest(createUpdate)(pair)

      case RemoveAListener(who) =>
        listeners = listeners.filter(_._1 ne who)
    }

  /**
   * Update the listeners with the message generated by createUpdate
   */
  protected def updateListeners() {
    val update = updateIfPassesTest(createUpdate) _
    listeners foreach update
  }

  /**
   * Update the listeners with a message that we create. Note that
   * with this invocation the createUpdate method is not used.
   */
  protected def updateListeners(msg: Any) {
    listeners foreach (_._1 ! msg)
  }

  /**
   * This method provides legacy functionality for filtering messages
   * before sending to each registered actor. It is deprecated in
   * favor of doing the filtering in the registered Actor's
   * message handling partial functions instead.
   */
  @deprecated("Accept/reject logic should be done in the partial function that handles the message.")
  protected def updateIfPassesTest(update: Any)(info: ActorTest) {
    info match {
      case (who, test) => if (test.isDefinedAt(update) && test(update)) who ! update
    }
  }

  /**
   * This method is called when the <pre>updateListeners()
method * needs a message to send to subscribed Actors. In particular, createUpdate * is used to create the first message that a newly subscribed CometListener * will receive. */ protected def createUpdate: Any /** * Override this method to process high priority messages. Note: * <b>you must not process messages with a wildcard (match all), since * this will intercept the messages used for subscription control. */ protected def highPriority: PartialFunction[Any, Unit] = Map.empty /** * Override this method to process medium priority messages. See * the highPriority method for an important note on wildcard * processing. * * @see #highPriority */ protected def mediumPriority: PartialFunction[Any, Unit] = Map.empty /** * Override this method to process low priority messages. */ protected def lowPriority: PartialFunction[Any, Unit] = Map.empty } /** * This is a legacy trait, left over from Lift's * Scala 2.7 support. You should use or migrate to * CometListener instead. * * @see CometListener */ @deprecated("Use the CometListener trait instead.") trait CometListenee extends CometListener { self: CometActor => } /** * A LiftActorJ with ListenerManager. Subclass this class * to get a Java-useable LiftActorJ with ListenerManager */ abstract class LiftActorJWithListenerManager extends LiftActorJ with ListenerManager { protected override def messageHandler: PartialFunction[Any, Unit] = highPriority orElse mediumPriority orElse listenerService orElse lowPriority orElse _messageHandler } /** * This trait adds functionality to automatically register with a given * Actor using AddAListener and RemoveAListener control messages. The most * typical usage would be to register with an instance of ListenerManager. * You will need to provide a def/val for the <pre>registerWith member * to control which Actor to connect to. * * See ListenerManager for a complete example. * * @see ListenerManager */ trait CometListener extends CometActor { self: CometActor => /** * This controls which Actor to register with for updates. Typically * this will be an instance of ListenerActor, although you can provide * your own subscription handling on top of any SimpleActor. */ protected def registerWith: SimpleActor[Any] /** * Override this in order to selectively update listeners based on the given message. * This method has been deprecated because it's executed in a seperate context from * the session's context. This causes problems. Accept/reject logic should be done * in the partial function that handles the message. */ @deprecated("Accept/reject logic should be done in the partial function that handles the message.") protected def shouldUpdate: PartialFunction[Any, Boolean] = { case _ => true} abstract override protected def localSetup() { registerWith ! AddAListener(this, shouldUpdate) super.localSetup() } abstract override protected def localShutdown() { registerWith ! RemoveAListener(this) super.localShutdown() } } trait LiftCometActor extends TypedActor[Any, Any] with ForwardableActor[Any, Any] with Dependent { def uniqueId: String private[http] def callInitCometActor(theSession: LiftSession, theType: Box[String], name: Box[String], defaultHtml: NodeSeq, attributes: Map[String, String]) { initCometActor(theSession, theType, name, defaultHtml, attributes) } protected def initCometActor(theSession: LiftSession, theType: Box[String], name: Box[String], defaultHtml: NodeSeq, attributes: Map[String, String]): Unit def jsonCall: JsonCall def theType: Box[String] def name: Box[String] def hasOuter: Boolean def buildSpan(time: Long, xml: NodeSeq): NodeSeq def parentTag: Elem /** * Poke the CometActor and cause it to do a partial update Noop which * will have the effect of causing the component to redisplay any * Wiring elements on the component. * This method is Actor-safe and may be called from any thread, not * just the Actor's message handler thread. */ def poke(): Unit = {} /** * Is this CometActor going to capture the initial Req * object? If yes, override this method and return true * and override captureInitialReq to capture the Req. Why * have to explicitly ask for the Req? In order to send Req * instances across threads, the Req objects must be snapshotted * which is the process of reading the POST or PUT body from the * HTTP request stream. We don't want to do this unless we * have to, so by default the Req is not snapshotted/sent. But * if you want it, you can have it. */ def sendInitialReq_? : Boolean = false /** * If the predicate cell changes, the Dependent will be notified */ def predicateChanged(which: Cell[_]): Unit = {poke()} /** * The locale for the session that created the CometActor */ def cometActorLocale: Locale = _myLocale private var _myLocale = Locale.getDefault() private[http] def setCometActorLocale(loc: Locale) { _myLocale = loc } } /** * Subclass from this class if you're in Java-land * and want a CometActor */ abstract class CometActorJ extends LiftActorJ with CometActor { override def lowPriority = _messageHandler } /** * Subclass from this class if you want a CometActorJ with * CometListeners */ abstract class CometActorJWithCometListener extends CometActorJ with CometListener { override def lowPriority = _messageHandler } /** * Takes care of the plumbing for building Comet-based Web Apps */ trait CometActor extends LiftActor with LiftCometActor with BindHelpers { private val logger = Logger(classOf[CometActor]) val uniqueId = Helpers.nextFuncName private var spanId = uniqueId private var lastRenderTime = Helpers.nextNum /** * If we're going to cache the last rendering, here's the * private cache */ private[this] var _realLastRendering: RenderOut = _ /** * The last rendering (cached or not) */ private def lastRendering: RenderOut = if (dontCacheRendering) { val ret = (render ++ jsonInCode): RenderOut theSession.updateFunctionMap(S.functionMap, spanId, lastRenderTime) ret } else { _realLastRendering } /** * set the last rendering... ignore if we're not caching */ private def lastRendering_=(last: RenderOut) { if (!dontCacheRendering) { _realLastRendering = last } } private var wasLastFullRender = false @transient private var listeners: List[(ListenerId, AnswerRender => Unit)] = Nil private var askingWho: Box[LiftCometActor] = Empty private var whosAsking: Box[LiftCometActor] = Empty private var answerWith: Box[Any => Any] = Empty private var deltas: List[Delta] = Nil private var jsonHandlerChain: PartialFunction[Any, JsCmd] = Map.empty private val notices = new ListBuffer[(NoticeType.Value, NodeSeq, Box[String])] private var lastListenTime = millis private var _theSession: LiftSession = _ def theSession = _theSession @volatile private var _defaultHtml: NodeSeq = _ @deprecated("Use defaultHtml") def defaultXml = _defaultHtml /** * The template that was passed to this component during comet * initializations */ def defaultHtml: NodeSeq = _defaultHtml private var _name: Box[String] = Empty /** * The optional name of this CometActors */ def name: Box[String] = _name private var _theType: Box[String] = Empty /** * The optional type of this CometActor */ def theType: Box[String] = _theType private var _attributes: Map[String, String] = Map.empty def attributes = _attributes /** * The lifespan of this component. By default CometActors * will last for the entire session that they were created in, * even if the CometActor is not currently visible. You can * set the lifespan of the CometActor. If the CometActor * isn't visible on any page for some period after its lifespan * the CometActor will be shut down. */ def lifespan: Box[TimeSpan] = Empty private var _running = true private var _shutDownAt = millis /** * Is the CometActor running? */ protected def running = _running /** * It's seriously suboptimal to override this method. Instead * use localSetup() */ protected def initCometActor(theSession: LiftSession, theType: Box[String], name: Box[String], defaultHtml: NodeSeq, attributes: Map[String, String]) { if (!dontCacheRendering) { lastRendering = RenderOut(Full(defaultHtml), Empty, Empty, Empty, false) } this._theType = theType this._theSession = theSession this._defaultHtml = defaultHtml this._name = name this._attributes = attributes } def defaultPrefix: Box[String] = Empty private lazy val _defaultPrefix: String = (defaultPrefix or _name) openOr "comet" /** * Set to 'true' if we should run "render" on every page load */ protected def devMode = false def hasOuter = true def parentTag = <div style="display: inline"/> /** * Return the list of ListenerIds of all long poll agents that * are waiting for this CometActor to change its state. This method * is useful for detecting presence. */ protected def cometListeners: List[ListenerId] = listeners.map(_._1) /** * This method will be called when there's a change in the long poll * listeners. The method does nothing, but allows you to get a granular * sense of how many browsers care about this CometActor. Note that * this method should not block for any material time and if there's * any processing to do, use Scheduler.schedule or send a message to this * CometActor. Do not change the Actor's state from this method. */ protected def listenerTransition(): Unit = {} private def _handleJson(in: Any): JsCmd = if (jsonHandlerChain.isDefinedAt(in)) jsonHandlerChain(in) else handleJson(in) /** * Prepends the handler to the Json Handlers. Should only be used * during instantiation * * @param h -- the PartialFunction that can handle a JSON request */ def appendJsonHandler(h: PartialFunction[Any, JsCmd]) { jsonHandlerChain = h orElse jsonHandlerChain } def handleJson(in: Any): JsCmd = Noop /** * If there's actor-specific JSON behavior on failure to make the JSON * call, include the JavaScript here. */ def onJsonError: Box[JsCmd] = Empty lazy val (jsonCall, jsonInCode) = S.buildJsonFunc(Full(_defaultPrefix), onJsonError, _handleJson) /** * Override this method to deal with JSON sent from the browser via the sendJson function. This * is based on the Lift JSON package rather than the handleJson stuff based on the older util.JsonParser. This * is the prefered mechanism. If you use the jsonSend call, you will get a JObject(JField("command", cmd), JField("param", params)) */ def receiveJson: PartialFunction[JsonAST.JValue, JsCmd] = Map() /** * The JavaScript call that you use to send the data to the server. For example: * <button onclick={jsonSend("Hello", JsRaw("Dude".encJs))}>Click</button> */ def jsonSend: JsonCall = _sendJson /** * The call that packages up the JSON and tosses it to the server. If you set autoIncludeJsonCode to true, * then this will be included in the stuff sent to the server. */ def jsonToIncludeInCode: JsCmd = _jsonToIncludeCode private lazy val (_sendJson, _jsonToIncludeCode) = S.createJsonFunc(Full(_defaultPrefix), onJsonError, receiveJson _) /** * Set this method to true to have the Json call code included in the Comet output */ def autoIncludeJsonCode: Boolean = false /** * Creates the span element acting as the real estate for commet rendering. */ def buildSpan(time: Long, xml: NodeSeq): NodeSeq = { Elem(parentTag.prefix, parentTag.label, parentTag.attributes, parentTag.scope, Group(xml)) % new UnprefixedAttribute("id", Text(spanId), if (time > 0L) { new PrefixedAttribute("lift", "when", time.toString, Null) } else {Null}) } protected override def messageHandler = { val what = composeFunction val myPf: PartialFunction[Any, Unit] = new PartialFunction[Any, Unit] { def apply(in: Any): Unit = CurrentCometActor.doWith(CometActor.this) { S.initIfUninitted(theSession) { RenderVersion.doWith(uniqueId) { S.functionLifespan(true) { what.apply(in) if (S.functionMap.size > 0) { theSession.updateFunctionMap(S.functionMap, uniqueId, lastRenderTime) S.clearFunctionMap } } } } } def isDefinedAt(in: Any): Boolean = CurrentCometActor.doWith(CometActor.this) { S.initIfUninitted(theSession) { RenderVersion.doWith(uniqueId) { S.functionLifespan(true) { what.isDefinedAt(in) } } } } } myPf } /** * A part of the CometActor's screen real estate that is not * updated by default with reRender(). This block of HTML is * useful for the editor part of a Comet-based control where * the data is JSON and updated with partialUpdates. */ def fixedRender: Box[NodeSeq] = Empty /** * Calculate fixedRender and capture the postpage javascript */ protected def calcFixedRender: Box[NodeSeq] = fixedRender.map(ns => theSession.postPageJavaScript() match { case Nil => ns case xs => { ns ++ Script(xs) } }) /** * We have to cache fixedRender and only change it if * the tempalte changes or we get a reRender(true) */ private def internalFixedRender: Box[NodeSeq] = if (!cacheFixedRender) { calcFixedRender } else { cachedFixedRender.get } private val cachedFixedRender: FatLazy[Box[NodeSeq]] = FatLazy(calcFixedRender) /** * By default, we do not cache the value of fixedRender. If it's * expensive to recompute it each time there's a convertion * of something to a RenderOut, override this method if you * want to cache fixedRender */ protected def cacheFixedRender = false /** * A helpful implicit conversion that takes a NodeSeq => NodeSeq * (for example a CssSel) and converts it to a Box[NodeSeq] by * applying the function to defaultHtml */ protected implicit def nodeSeqFuncToBoxNodeSeq(f: NodeSeq => NodeSeq): Box[NodeSeq] = Full(f(defaultHtml)) /** * Handle messages sent to this Actor before the */ def highPriority: PartialFunction[Any, Unit] = Map.empty def lowPriority: PartialFunction[Any, Unit] = Map.empty def mediumPriority: PartialFunction[Any, Unit] = Map.empty private[http] def _lowPriority: PartialFunction[Any, Unit] = { case s => logger.debug("CometActor " + this + " got unexpected message " + s) } private lazy val _mediumPriority: PartialFunction[Any, Unit] = { case l@Unlisten(seq) => { lastListenTime = millis askingWho match { case Full(who) => forwardMessageTo(l, who) // forward l case _ => listeners = listeners.filter(_._1 != seq) } listenerTransition() } case l@Listen(when, seqId, toDo) => { lastListenTime = millis askingWho match { case Full(who) => forwardMessageTo(l, who) // who forward l case _ => if (when < lastRenderTime) { toDo(AnswerRender(new XmlOrJsCmd(spanId, lastRendering, buildSpan _, notices toList), whosAsking openOr this, lastRenderTime, wasLastFullRender)) clearNotices } else { deltas.filter(_.when > when) match { case Nil => listeners = (seqId, toDo) :: listeners case all@(hd :: xs) => toDo(AnswerRender(new XmlOrJsCmd(spanId, Empty, Empty, Full(all.reverse.foldLeft(Noop)(_ & _.js)), Empty, buildSpan, false, notices toList), whosAsking openOr this, hd.when, false)) clearNotices } } } listenerTransition() } case PerformSetupComet2(initialReq) => { // this ! RelinkToActorWatcher localSetup() captureInitialReq(initialReq) performReRender(true) } /** * Update the defaultHtml... sent in dev mode */ case UpdateDefaultXml(xml) => { val redo = xml != _defaultHtml _defaultHtml = xml if (redo) { performReRender(false) } } case AskRender => askingWho match { case Full(who) => forwardMessageTo(AskRender, who) // forward AskRender case _ => { if (!deltas.isEmpty || devMode) performReRender(false) reply(AnswerRender(new XmlOrJsCmd(spanId, lastRendering, buildSpan _, notices toList), whosAsking openOr this, lastRenderTime, true)) clearNotices } } case ActionMessageSet(msgs, req) => S.doCometParams(req.params) { S.jsToAppend() match { case Nil => case js => partialUpdate(js) } reply(msgs.map(_()) ::: List(S.noticesToJsCmd)) } case AskQuestion(what, who, otherlisteners) => { this.spanId = who.uniqueId this.listeners = otherlisteners ::: this.listeners startQuestion(what) whosAsking = Full(who) this.reRender(true) listenerTransition() } case AnswerQuestion(what, otherListeners) => askingWho.foreach { ah => { reply("A null message to release the actor from its send and await reply... do not delete this message") // askingWho.unlink(self) ah ! ShutDown this.listeners = this.listeners ::: otherListeners this.askingWho = Empty val aw = answerWith answerWith = Empty aw.foreach(_(what)) performReRender(true) listenerTransition() } } case ShutdownIfPastLifespan => for{ ls <- lifespan if listeners.isEmpty && (lastListenTime + ls.millis) < millis } { this ! ShutDown } case ReRender(all) => performReRender(all) case Error(id, node) => notices += ((NoticeType.Error, node, id)) case Warning(id, node) => notices += ((NoticeType.Warning, node, id)) case Notice(id, node) => notices += ((NoticeType.Notice, node, id)) case ClearNotices => clearNotices case ShutDown => logger.info("The CometActor " + this + " Received Shutdown") askingWho.foreach(_ ! ShutDown) theSession.removeCometActor(this) _localShutdown() case PartialUpdateMsg(cmdF) => { val cmd: JsCmd = cmdF.apply val time = Helpers.nextNum val delta = JsDelta(time, cmd) theSession.updateFunctionMap(S.functionMap, uniqueId, time) S.clearFunctionMap val m = millis deltas = (delta :: deltas).filter(d => (m - d.timestamp) < 120000L) if (!listeners.isEmpty) { val postPage = theSession.postPageJavaScript() val rendered = AnswerRender(new XmlOrJsCmd(spanId, Empty, Empty, Full(cmd & postPage), Empty, buildSpan, false, notices toList), whosAsking openOr this, time, false) clearNotices listeners.foreach(_._2(rendered)) listeners = Nil listenerTransition() } } } /** * It's the main method to override, to define what is rendered by the CometActor * * There are implicit conversions for a bunch of stuff to * RenderOut (including NodeSeq). Thus, if you don't declare the return * turn to be something other than RenderOut and return something that's * coersable into RenderOut, the compiler "does the right thing"(tm) for you. * <br/> * There are implicit conversions for NodeSeq, so you can return a pile of * XML right here. There's an implicit conversion for NodeSeq => NodeSeq, * so you can return a function (e.g., a CssBindFunc) that will convert * the defaultHtml to the correct output. There's an implicit conversion * from JsCmd, so you can return a pile of JavaScript that'll be shipped * to the browser.<br/> * Note that the render method will be called each time a new browser tab * is opened to the comet component or the comet component is otherwise * accessed during a full page load (this is true if a partialUpdate * has occured.) You may want to look at the fixedRender method which is * only called once and sets up a stable rendering state. */ def render: RenderOut /** * Cause the entire component to be reRendered and pushed out * to any listeners. This method will cause the entire component * to be rendered which can result in a huge blob of JavaScript to * be sent to the client. It's a much better practice to use * partialUpdate for non-trivial CometActor components. * * @param sendAll -- Should the fixed part of the CometActor be * rendered. */ def reRender(sendAll: Boolean) { this ! ReRender(sendAll) } /** * Cause the entire component to be reRendered and pushed out * to any listeners. This method will cause the entire component * to be rendered which can result in a huge blob of JavaScript to * be sent to the client. It's a much better practice to use * partialUpdate for non-trivial CometActor components. */ def reRender() {reRender(false)} /** * Set this method to true if you want to avoid caching the * rendering. This trades space for time. */ protected def dontCacheRendering: Boolean = false /** * Clear the common dependencies for Wiring. This * method will clearPostPageJavaScriptForThisPage() and * unregisterFromAllDependencies(). The combination * will result in a clean slate for Wiring during a redraw. * You can change the behavior of the wiring dependency management * by overriding this method */ protected def clearWiringDependencies() { if (!manualWiringDependencyManagement) { theSession.clearPostPageJavaScriptForThisPage() unregisterFromAllDepenencies() } } /** * By default, Lift deals with managing wiring dependencies. * This means on each full render (a full render will * happen on reRender() or on a page load if there have been * partial updates.) You may want to manually deal with * wiring dependencies. If you do, override this method * and return true */ protected def manualWiringDependencyManagement = false private def performReRender(sendAll: Boolean) { lastRenderTime = Helpers.nextNum if (sendAll) { cachedFixedRender.reset } if (sendAll || !cacheFixedRender) { clearWiringDependencies() } wasLastFullRender = sendAll & hasOuter deltas = Nil if (!dontCacheRendering) { lastRendering = render ++ jsonInCode } theSession.updateFunctionMap(S.functionMap, spanId, lastRenderTime) val rendered: AnswerRender = AnswerRender(new XmlOrJsCmd(spanId, lastRendering, buildSpan _, notices toList), this, lastRenderTime, sendAll) clearNotices listeners.foreach(_._2(rendered)) listeners = Nil } def unWatch = partialUpdate(Call("liftComet.lift_unlistWatch", uniqueId)) /** * Poke the CometActor and cause it to do a partial update Noop which * will have the effect of causing the component to redisplay any * Wiring elements on the component. * This method is Actor-safe and may be called from any thread, not * just the Actor's message handler thread. */ override def poke(): Unit = { if (running) { partialUpdate(Noop) } } /** * Perform a partial update of the comet component based * on the JsCmd. This means that the JsCmd will be sent to * all of the currently listening browser tabs. This is the * preferred method over reRender to update the component */ protected def partialUpdate(cmd: => JsCmd) { this ! PartialUpdateMsg(() => cmd) } protected def startQuestion(what: Any) {} /** * This method will be called after the Actor has started. Do any setup here. * DO NOT do initialization in the constructor or in initCometActor... do it here. */ protected def localSetup(): Unit = {} /** * Comet Actors live outside the HTTP request/response cycle. * However, it may be useful to know what Request led to the * creation of the CometActor. You can override this method * and capture the initial Req object. Note that keeping a reference * to the Req may lead to memory retention issues if the Req contains * large message bodies, etc. It's optimal to capture the path * or capture any request parameters that you care about rather * the keeping the whole Req reference. */ protected def captureInitialReq(initialReq: Box[Req]) {} private def _localShutdown() { localShutdown() clearNotices listeners = Nil askingWho = Empty whosAsking = Empty deltas = Nil jsonHandlerChain = Map.empty _running = false _shutDownAt = millis } /** * This method will be called as part of the shut-down of the actor. Release any resources here. */ protected def localShutdown(): Unit = {} /** * Compose the Message Handler function. By default, * composes highPriority orElse mediumePriority orElse internalHandler orElse * lowPriority orElse internalHandler. But you can change how * the handler works if doing stuff in highPriority, mediumPriority and * lowPriority is not enough */ protected def composeFunction: PartialFunction[Any, Unit] = composeFunction_i private def composeFunction_i: PartialFunction[Any, Unit] = { // if we're no longer running don't pass messages to the other handlers // just pass them to our handlers if (!_running && (millis - 20000L) > _shutDownAt) _mediumPriority orElse _lowPriority else highPriority orElse mediumPriority orElse _mediumPriority orElse lowPriority orElse _lowPriority } /** * A helper for binding which uses the defaultHtml property. */ def bind(prefix: String, vals: BindParam*): NodeSeq = bind(prefix, _defaultHtml, vals: _*) /** * A helper for binding which uses the defaultHtml property and the * default prefix. */ def bind(vals: BindParam*): NodeSeq = bind(_defaultPrefix, vals: _*) /** * Ask another CometActor a question. That other CometActor will * take over the screen real estate until the question is answered. */ protected def ask(who: LiftCometActor, what: Any)(answerWith: Any => Unit) { who.callInitCometActor(theSession, Full(who.uniqueId), name, defaultHtml, attributes) theSession.addCometActor(who) // who.link(this) who ! PerformSetupComet2(Empty) askingWho = Full(who) this.answerWith = Full(answerWith) who ! AskQuestion(what, this, listeners) // this ! AskRender } protected def answer(answer: Any) { whosAsking.foreach(_ !? AnswerQuestion(answer, listeners)) whosAsking = Empty performReRender(false) } /** * Convert a NodeSeq => NodeSeq to a RenderOut. The render method * returns a RenderOut. This method implicitly (in Scala) or explicitly * (in Java) will convert a NodeSeq => NodeSeq to a RenderOut. This * is helpful if you use Lift's CSS Seletor Transforms to define * rendering. */ protected implicit def nsToNsFuncToRenderOut(f: NodeSeq => NodeSeq) = new RenderOut((Box !! defaultHtml).map(f), internalFixedRender, if (autoIncludeJsonCode) Full(jsonToIncludeInCode & S.jsToAppend()) else { S.jsToAppend match { case Nil => Empty case x :: Nil => Full(x) case xs => Full(xs.reduceLeft(_ & _)) } }, Empty, false) /** * Convert a Seq[Node] (the superclass of NodeSeq) to a RenderOut. * The render method * returns a RenderOut. This method implicitly (in Scala) or explicitly * (in Java) will convert a NodeSeq to a RenderOut. This * is helpful if you return a NodeSeq from your render method. */ protected implicit def arrayToRenderOut(in: Seq[Node]): RenderOut = new RenderOut(Full(in: NodeSeq), internalFixedRender, if (autoIncludeJsonCode) Full(jsonToIncludeInCode & S.jsToAppend()) else { S.jsToAppend match { case Nil => Empty case x :: Nil => Full(x) case xs => Full(xs.reduceLeft(_ & _)) } }, Empty, false) protected implicit def jsToXmlOrJsCmd(in: JsCmd): RenderOut = new RenderOut(Empty, internalFixedRender, if (autoIncludeJsonCode) Full(in & jsonToIncludeInCode & S.jsToAppend()) else Full(in & S.jsToAppend()), Empty, false) implicit def pairToPair(in: (String, Any)): (String, NodeSeq) = (in._1, Text(in._2 match {case null => "null" case s => s.toString})) implicit def nodeSeqToFull(in: NodeSeq): Box[NodeSeq] = Full(in) implicit def elemToFull(in: Elem): Box[NodeSeq] = Full(in) /** * Similar with S.error */ def error(n: String) {error(Text(n))} /** * Similar with S.error */ def error(n: NodeSeq) {notices += ((NoticeType.Error, n, Empty))} /** * Similar with S.error */ def error(id: String, n: NodeSeq) {notices += ((NoticeType.Error, n, Full(id)))} /** * Similar with S.error */ def error(id: String, n: String) {error(id, Text(n))} /** * Similar with S.notice */ def notice(n: String) {notice(Text(n))} /** * Similar with S.notice */ def notice(n: NodeSeq) {notices += ((NoticeType.Notice, n, Empty))} /** * Similar with S.notice */ def notice(id: String, n: NodeSeq) {notices += ((NoticeType.Notice, n, Full(id)))} /** * Similar with S.notice */ def notice(id: String, n: String) {notice(id, Text(n))} /** * Similar with S.warning */ def warning(n: String) {warning(Text(n))} /** * Similar with S.warning */ def warning(n: NodeSeq) {notices += ((NoticeType.Warning, n, Empty))} /** * Similar with S.warning */ def warning(id: String, n: NodeSeq) {notices += ((NoticeType.Warning, n, Full(id)))} /** * Similar with S.warning */ def warning(id: String, n: String) {warning(id, Text(n))} private def clearNotices {notices clear} } abstract class Delta(val when: Long) { def js: JsCmd val timestamp = millis } case class JsDelta(override val when: Long, js: JsCmd) extends Delta(when) sealed abstract class CometMessage /** * Impersonates the actual comet response content */ private[http] class XmlOrJsCmd(val id: String, _xml: Box[NodeSeq], _fixedXhtml: Box[NodeSeq], val javaScript: Box[JsCmd], val destroy: Box[JsCmd], spanFunc: (Long, NodeSeq) => NodeSeq, ignoreHtmlOnJs: Boolean, notices: List[(NoticeType.Value, NodeSeq, Box[String])]) { def this(id: String, ro: RenderOut, spanFunc: (Long, NodeSeq) => NodeSeq, notices: List[(NoticeType.Value, NodeSeq, Box[String])]) = this (id, ro.xhtml, ro.fixedXhtml, ro.script, ro.destroyScript, spanFunc, ro.ignoreHtmlOnJs, notices) val xml = _xml.flatMap(content => S.session.map(s => s.processSurroundAndInclude("JS SetHTML id: " + id, content))) val fixedXhtml = _fixedXhtml.flatMap(content => S.session.map(s => s.processSurroundAndInclude("JS SetHTML id: " + id, content))) /** * Returns the JsCmd that will be sent to client */ def toJavaScript(session: LiftSession, displayAll: Boolean): JsCmd = { var ret: JsCmd = JsCmds.JsTry(JsCmds.Run("destroy_" + id + "();"), false) & ((if (ignoreHtmlOnJs) Empty else xml, javaScript, displayAll) match { case (Full(xml), Full(js), false) => LiftRules.jsArtifacts.setHtml(id, Helpers.stripHead(xml)) & JsCmds.JsTry(js, false) case (Full(xml), _, false) => LiftRules.jsArtifacts.setHtml(id, Helpers.stripHead(xml)) case (Full(xml), Full(js), true) => LiftRules.jsArtifacts.setHtml(id + "_outer", ( spanFunc(0, Helpers.stripHead(xml)) ++ fixedXhtml.openOr(Text("")))) & JsCmds.JsTry(js, false) case (Full(xml), _, true) => LiftRules.jsArtifacts.setHtml(id + "_outer", ( spanFunc(0, Helpers.stripHead(xml)) ++ fixedXhtml.openOr(Text("")))) case (_, Full(js), _) => js case _ => JsCmds.Noop }) & JsCmds.JsTry(JsCmds.Run("destroy_" + id + " = function() {" + (destroy.openOr(JsCmds.Noop).toJsCmd) + "};"), false) S.appendNotices(notices) ret = S.noticesToJsCmd & ret ret } def inSpan: NodeSeq = xml.openOr(Text("")) ++ javaScript.map(s => Script(s)).openOr(Text("")) def outSpan: NodeSeq = Script(Run("var destroy_" + id + " = function() {" + (destroy.openOr(JsCmds.Noop).toJsCmd) + "}")) ++ fixedXhtml.openOr(Text("")) } /** * Update the comet XML on each page reload in dev mode */ case class UpdateDefaultXml(xml: NodeSeq) extends CometMessage case class PartialUpdateMsg(cmd: () => JsCmd) extends CometMessage case object AskRender extends CometMessage case class AnswerRender(response: XmlOrJsCmd, who: LiftCometActor, when: Long, displayAll: Boolean) extends CometMessage case class PerformSetupComet2(initialReq: Box[Req]) extends CometMessage case object ShutdownIfPastLifespan extends CometMessage case class AskQuestion(what: Any, who: LiftCometActor, listeners: List[(ListenerId, AnswerRender => Unit)]) extends CometMessage case class AnswerQuestion(what: Any, listeners: List[(ListenerId, AnswerRender => Unit)]) extends CometMessage case class Listen(when: Long, uniqueId: ListenerId, action: AnswerRender => Unit) extends CometMessage case class Unlisten(uniqueId: ListenerId) extends CometMessage case class ActionMessageSet(msg: List[() => Any], req: Req) extends CometMessage case class ReRender(doAll: Boolean) extends CometMessage case class ListenerId(id: Long) case class Error(id: Box[String], msg: NodeSeq) extends CometMessage case class Warning(id: Box[String], msg: NodeSeq) extends CometMessage case class Notice(id: Box[String], msg: NodeSeq) extends CometMessage case object ClearNotices extends CometMessage object Error { def apply(node: NodeSeq): Error = Error(Empty, node) def apply(node: String): Error = Error(Empty, Text(node)) def apply(id: String, node: String): Error = Error(Full(id), Text(node)) def apply(id: String, node: NodeSeq): Error = Error(Full(id), node) } object Warning { def apply(node: NodeSeq): Warning = Warning(Empty, node) def apply(node: String): Warning = Warning(Empty, Text(node)) def apply(id: String, node: String): Warning = Warning(Full(id), Text(node)) def apply(id: String, node: NodeSeq): Warning = Warning(Full(id), node) } object Notice { def apply(node: NodeSeq): Notice = Notice(Empty, node) def apply(node: String): Notice = Notice(Empty, Text(node)) def apply(id: String, node: String): Notice = Notice(Full(id), Text(node)) def apply(id: String, node: NodeSeq): Notice = Notice(Full(id), node) } /** * The RenderOut case class contains the rendering for the CometActor. * Because of the implicit conversions, RenderOut can come from * <br/> * @param xhtml is the "normal" render body * @param fixedXhtml is the "fixed" part of the body. This is ignored unless reRender(true) * @param script is the script to be executed on render. This is where you want to put your script * @param destroyScript is executed when the comet widget is redrawn ( e.g., if you register drag or mouse-over or some events, you unregister them here so the page doesn't leak resources.) * @param ignoreHtmlOnJs -- if the reason for sending the render is a Comet update, ignore the xhtml part and just run the JS commands. This is useful in IE when you need to redraw the stuff inside <table>
... just doing innerHtml on
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