* override def body: PartialFunction[Any, Unit] = {
* case Ping =>
* println("got a ping")
* reply("pong")
*
* case OneWay =>
* println("got a oneway")
* }
*
*/
def body: PartialFunction[Any, Unit]
/**
* Callback method that is called during initialization.
* To be implemented by subclassing server.
*/
def init(config: AnyRef) {}
/**
* Callback method that is called during reinitialization after a server crash.
* To be implemented by subclassing server.
*/
def reinit(config: AnyRef) {}
/**
* Callback method that is called during termination.
* To be implemented by subclassing server.
*/
def shutdown(reason: AnyRef) {}
def act = loop { react { genericBase orElse actorBase } }
private def actorBase: PartialFunction[Any, Unit] = hotswap getOrElse body
private var hotswap: Option[PartialFunction[Any, Unit]] = None
private val genericBase: PartialFunction[Any, Unit] = {
case Init(config) => init(config)
case ReInit(config) => reinit(config)
case HotSwap(code) => hotswap = code
case Shutdown(reason) => shutdown(reason); reply('success)
case Terminate(reason) => exit(reason)
}
}
/**
* The container (proxy) for GenericServer, responsible for managing the life-cycle of the server;
* such as shutdown, restart, re-initialization etc.
* Each GenericServerContainer manages one GenericServer.
*
* @author Jonas Bonér
*/
class GenericServerContainer(
val id: String,
var serverFactory: () => GenericServer,
private[kernel] var state: Option[TransientObjectState]) extends Logging {
require(id != null && id != "")
// TODO: see if we can parameterize class and add type safe getActor method
//class GenericServerContainer[T <: GenericServer](var factory: () => T) {
//def getActor: T = server
var lifeCycle: Option[LifeCycle] = None
val lock = new ReadWriteLock
private var server: GenericServer = _
private var currentConfig: Option[AnyRef] = None
private var timeout = 5000
/**
* Sends a one way message to the server - alias for cast(message).
* * Example: *
* server ! Message **/ def !(message: Any) = { require(server != null) lock.withReadLock { server ! message } } /** * Sends a message to the server returns a FutureWithTimeout holding the future reply . *
* Example: *
* val future = server !! Message
* future.receiveWithin(100) match {
* case None => ... // timed out
* case Some(reply) => ... // handle reply
* }
*
*/
def !: FutureWithTimeout[T] = {
require(server != null)
lock.withReadLock { server !!! message }
}
/**
* Sends a message to the server and blocks indefinitely (no time out), waiting for the reply.
* * Example: *
* val result: String = server !? Message **/ def !?[T](message: Any): T = { require(server != null) val future: Future[T] = lock.withReadLock { server.! } Actor.receive { case (future.ch ! arg) => arg.asInstanceOf[T] } } /** * Sends a message to the server and gets a future back with the reply. Returns * an Option with either Some(result) if succesful or None if timeout. *
* Timeout specified by the setTimeout(time: Int) method.
*
* Example: *
* (server !!! Message).getOrElse(throw new RuntimeException("time out")
*
*/
def !!: Option[T] = {
require(server != null)
val future: FutureWithTimeout[T] = lock.withReadLock { server !!! message }
future.receiveWithin(timeout)
}
/**
* Sends a message to the server and gets a future back with the reply.
* * Tries to get the reply within the timeout specified in the GenericServerContainer * and else execute the error handler (which can return a default value, throw an exception * or whatever is appropriate). *
* Example: *
* server !!! (Message, throw new RuntimeException("time out"))
* // OR
* server !!! (Message, DefaultReturnValue)
*
*/
def !!: T = !!!(message, errorHandler, timeout)
/**
* Sends a message to the server and gets a future back with the reply.
* * Tries to get the reply within the timeout specified as parameter to the method * and else execute the error handler (which can return a default value, throw an exception * or whatever is appropriate). *
* Example: *
* server !!! (Message, throw new RuntimeException("time out"), 1000)
* // OR
* server !!! (Message, DefaultReturnValue, 1000)
*
*/
def !!: T = {
require(server != null)
val future: FutureWithTimeout[T] = lock.withReadLock { server !!! message }
future.receiveWithin(time) match {
case None => errorHandler
case Some(reply) => reply
}
}
/**
* Initializes the server by sending a Init(config) message.
*/
def init(config: AnyRef) = lock.withWriteLock {
currentConfig = Some(config)
server ! Init(config)
}
/**
* Re-initializes the server by sending a ReInit(config) message with the most recent configuration.
*/
def reinit = lock.withWriteLock {
currentConfig match {
case Some(config) => server ! ReInit(config)
case None => {}
}
}
/**
* Hotswaps the server body by sending it a HotSwap(code) with the new code
* block (PartialFunction) to be executed.
*/
def hotswap(code: Option[PartialFunction[Any, Unit]]) = lock.withReadLock { server ! HotSwap(code) }
/**
* Swaps the server factory, enabling creating of a completely new server implementation
* (upon failure and restart).
*/
def swapFactory(newFactory: () => GenericServer) = serverFactory = newFactory
/**
* Sets the timeout for the call(..) method, e.g. the maximum time to wait for a reply
* before bailing out. Sets the timeout on the future return from the call to the server.
*/
def setTimeout(time: Int) = timeout = time
/**
* Returns the next message in the servers mailbox.
*/
def nextMessage = lock.withReadLock { server ? }
/**
* Creates a new actor for the GenericServerContainer, and return the newly created actor.
*/
private[kernel] def newServer(): GenericServer = lock.withWriteLock {
server = serverFactory()
server
}
/**
* Starts the server.
*/
private[kernel] def start = lock.withReadLock { server.start }
/**
* Terminates the server with a reason by sending a Terminate(Some(reason)) message.
*/
private[kernel] def terminate(reason: AnyRef) = lock.withReadLock { server ! Terminate(reason) }
/**
* Terminates the server with a reason by sending a Terminate(Some(reason)) message,
* the shutdownTime defines the maximal time to wait for the server to shutdown before
* killing it.
*/
private[kernel] def terminate(reason: AnyRef, shutdownTime: Int) = lock.withReadLock {
if (shutdownTime > 0) {
log.debug("Waiting [%s milliseconds for the server to shut down before killing it.", shutdownTime)
// server !? (shutdownTime, Shutdown(reason)) match {
server !? Shutdown(reason) match {
case Some('success) => log.debug("Server [%s] has been shut down cleanly.", id)
case None => log.warning("Server [%s] was **not able** to complete shutdown cleanly within its configured shutdown time [%s]", id, shutdownTime)
}
}
server ! Terminate(reason)
}
private[kernel] def reconfigure(reason: AnyRef, restartedServer: GenericServer, supervisor: Supervisor) = lock.withWriteLock {
server = restartedServer
reinit
}
private[kernel] def getServer: GenericServer = server
private[kernel] def cloneServerAndReturnOldVersion: GenericServer = lock.withWriteLock {
val oldServer = server
server = Serializer.deepClone(server)
oldServer
}
private[kernel] def swapServer(newServer: GenericServer) = lock.withWriteLock {
server = newServer
}
}