Remote Control Library

The remote control library was an inception that originally started here, and details ironed out on my blog. This library gives a client the ability to swap out dynamic portions of code, or send arbitrary commands to server (which is just a nice wrapper for Scala RemoteActors).

Requirements

• sbt 0.7.4

Changing Code Real-Time

Changing server side code is fairly easy. In your long running process (web server, irc robot, computer game, etc), wrap your potentially dynamic portions like so:

import com.philipcali.hotcode.HotSwap._

class LongRunningProcess {
  // Implementaions details
  def onMessage(msg: String) {
    dynamic('message, msg) {
      println("Printing out %s" format(msg))
    }
  }
}

Calling dynamic, labels that code as replaceable. Change this code like this:

import com.philipcali.hotcode.HotSwap._

update('message) {
  case Context(msg: String) =>
    println("Changing code, dude! %s" format(msg))
}

That's all there is to it.

Executing Commands

Using our LongRunningProcess example, simple inherit from the RemoteControlled trait.

class LongRunningProcess extends RemoteControlled {
  ...
  def name = "Remote Control"
  def version = "0.1"
}

Clients can send arbitrary calls through the Controller object.

import com.philipcali.control.Controller._
import com.philipcali.signals._

// Sends one way command
connect('remote) signal(Computation({
  case _ => println("Doing it big!")
}))

// Sends command expecting results
connect('remote) signal(Computation({
  case Context(self: LongRunningProcess) =>
    "%s v%s" format(self.name, self.version)
})) match {
  // Will print out Remote Control v0.1 
  case Some(resp: String) => println(resp)
}

Use at your own risk.