[simgrid.git] / examples / python / actor-create / actor-create.py

# Copyright (c) 2006-2018. The SimGrid Team. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the license (GNU LGPL) which comes with this package.

# This example shows how to declare and start your actors.
#
# The first step is to declare the code of your actors (what they do exactly does not matter to this example) and then
# you ask SimGrid to start your actors. There is three ways of doing so:
# - Directly, by instantiating your actor as paramter to Actor::create()
# - By first registering your actors before instantiating it;
# - Through the deployment file.
#
# This example shows all these solutions, even if you obviously should use only one of these solutions to start your
# actors. The most advised solution is to use a deployment file, as it creates a clear separation between your
# application and the settings to test it. This is a better scientific methodology. Actually, starting an actor with
# Actor.create() is mostly useful to start an actor from another actor.

import simgrid, sys

# Our first class of actors is simply implemented with a function, that takes a single string as parameter.
#
# Later, this actor class is instantiated within the simulation.
def receiver(mailbox_name):
  mailbox = simgrid.Mailbox.by_name(mailbox_name)

  simgrid.info("Hello s4u, I'm ready to get any message you'd want on {:s}".format(mailbox.get_name()))

  msg1 = mailbox.get()
  msg2 = mailbox.get()
  msg3 = mailbox.get()
  simgrid.info("I received '{:s}', '{:s}' and '{:s}'".format(msg1, msg2, msg3))
  simgrid.info("I'm done. See you.")

# Our second class of actors is also a function
def forwarder(*args):
  if len(args) < 2: raise AssertionError("Actor forwarder requires 2 parameters, but got only {:d}".format(len(args)))
  mb_in  = simgrid.Mailbox.by_name(args[0])
  mb_out = simgrid.Mailbox.by_name(args[1])
  
  msg = mb_in.get()
  simgrid.info("Forward '{:s}'.".format(msg))
  mb_out.put(msg, len(msg))

# Declares a third class of actors which sends a message to the mailbox 'mb42'.
# The sent message is what was passed as parameter on creation (or 'GaBuZoMeu' by default)
#
# Later, this actor class is instantiated twice in the simulation.
class Sender:
  mbox  = "mb42"
  msg = "GaBuZoMeu";
  def __init__(self, *args):
      if len(args) > 0: self.msg  = args[0];
      if len(args) > 1: self.mbox = args[1];
      if len(args) > 2: raise AssertionError("Actor sender requires 2 parameters, but got only {:d}".format(len(args)))

  def __call__(self):
      simgrid.info("Hello s4u, I have something to send")
      mailbox = simgrid.Mailbox.by_name(self.mbox)

      mailbox.put(self.msg, len(self.msg))
      simgrid.info("I'm done. See you.")

# Here comes the main function of your program
if __name__ == '__main__':
  # When your program starts, you have to first start a new simulation engine, as follows
  e = simgrid.Engine(sys.argv)

  # Then you should load a platform file, describing your simulated platform
  e.load_platform("../platforms/small_platform.xml");

  # And now you have to ask SimGrid to actually start your actors.
  #
  # The easiest way to do so is to implement the behavior of your actor in a single function,
  # as we do here for the receiver actors. This function can take any kind of parameters, as
  # long as the last parameters of Actor::create() match what your function expects.
  simgrid.Actor.create("receiver", simgrid.Host.by_name("Fafard"), receiver, "mb42")

  # If your actor is getting more complex, you probably want to implement it as a class instead,
  # as we do here for the sender actors. The main behavior goes into operator()() of the class.
  #
  # You can then directly start your actor, as follows:
  simgrid.Actor.create("sender1", simgrid.Host.by_name("Tremblay"), Sender())
  # If you want to pass parameters to your class, that's very easy: just use your constructors
  simgrid.Actor.create("sender2", simgrid.Host.by_name("Jupiter"), Sender("GloubiBoulga"));

  # But starting actors directly is considered as a bad experimental habit, since it ties the code
  # you want to test with the experimental scenario. Starting your actors from an external deployment
  # file in XML ensures that you can test your code in several scenarios without changing the code itself.
  #
  # For that, you first need to register your function or your actor as follows.
  e.register_actor("sender", Sender)
  e.register_actor("forwarder", forwarder)
  # Once actors and functions are registered, just load the deployment file 
  e.load_deployment("actor-create/actor-create_d.xml")

  # Once every actors are started in the engine, the simulation can start
  e.run();

  # Once the simulation is done, the program is ended