storyboard: Allow destroying of a DIF

This allows the destroying of a DIF while the experiment is
running. This to ease the emulation of failures in the network.

3 files changed, 24 insertions, 0 deletions

diff --git a/rumba/elements/experimentation.py b/rumba/elements/experimentation.py
index 09cfc84..1ae50f7 100644
--- a/rumba/elements/experimentation.py
+++ b/rumba/elements/experimentation.py
@@ -479,6 +479,10 @@ class Experiment(object):
         logger.info("Bootstrap took %.2f seconds", end - start)
 
     @abc.abstractmethod
+    def destroy_dif(self, dif):
+        raise Exception('destroy_dif() method not implemented')
+
+    @abc.abstractmethod
     def _install_prototype(self):
         raise Exception('install_prototype() method not implemented')
 
diff --git a/rumba/prototypes/ouroboros.py b/rumba/prototypes/ouroboros.py
index 1402180..a7a7fc9 100644
--- a/rumba/prototypes/ouroboros.py
+++ b/rumba/prototypes/ouroboros.py
@@ -246,3 +246,7 @@ class Experiment(mod.Experiment):
         if isinstance(self.testbed, local.Testbed):
             logger.info("Killing IRMd...")
             subprocess.check_call('sudo killall -15 irmd'.split())
+
+    def destroy_dif(self, dif):
+        for ipcp in dif.ipcps:
+            ipcp.node.execute_command('irm i d n ' + ipcp.name)
diff --git a/rumba/storyboard.py b/rumba/storyboard.py
index 6b56a92..c652073 100644
--- a/rumba/storyboard.py
+++ b/rumba/storyboard.py
@@ -1065,6 +1065,22 @@ class StoryBoard(_SBEntity):
         """
         self.schedule_node_state(t, node, 'down')
 
+    def schedule_destroy_dif(self, t, dif):
+        """
+        Destroys a DIF at the specified time.
+
+        :param t: the time in the storyboard at which the state
+                  change should happen
+        :type t: `float`
+        :param dif: the DIF which should go down
+        :type dif: `rumba.model.DIF`
+        """
+        if self.experiment is None:
+            raise ValueError("An experiment is needed to schedule commands.")
+
+        action = functools.partial(self.experiment.destroy_dif, dif)
+        self.add_event(Event(action, ev_time=t))
+
     def write_script(self, buffer):
         """
         Writes the script on a (string-oriented) buffer,