testbeds: Add default image for docker testbed

This adds a default image for the docker testbed for Ouroboros so it
is easier for an experimenter to start experimenting with the docker
testbed, similarly to the QEMU testbed.

1 files changed, 18 insertions, 7 deletions

diff --git a/rumba/testbeds/dockertb.py b/rumba/testbeds/dockertb.py
index 2ee4561..5dcbb16 100644
--- a/rumba/testbeds/dockertb.py
+++ b/rumba/testbeds/dockertb.py
@@ -39,8 +39,8 @@ class Testbed(mod.Testbed):
     """
     Represents a docker testbed.
     """
-    def __init__(self, base_image, exp_name='foo', pull_image=True,
-                 use_ovs=False):
+    def __init__(self, base_image=None, exp_name='foo',
+                 pull_image=True, use_ovs=False):
         """
         Initializes the testbed class.
 
@@ -48,14 +48,13 @@ class Testbed(mod.Testbed):
         :param base_image: The docker base image.
         :param pull_image: Retrieve the docker image from the Docker hub?
         :param use_ovs: Use the OVS switch instead of the Linux bridge?
+
+        .. note:: In case no base image is provided, Rumba will automatically
+                  download the latest version available from docker hub.
         """
         mod.Testbed.__init__(self, exp_name, "", "", "")
 
-        img = base_image.rsplit(":", 1)
-
-        self.base_image_repo = img[0]
-        self.base_image_tag = "latest" if len(img) == 1 else img[1]
-        self.base_image = "%s:%s" % (self.base_image_repo, self.base_image_tag)
+        self.base_image = base_image
         self.pull_image = pull_image
         self.use_ovs = use_ovs
 
@@ -69,6 +68,18 @@ class Testbed(mod.Testbed):
     def _swap_in(self, experiment):
         docker_client = self.docker_client
 
+        if not self.base_image:
+            if experiment.prototype_name() == 'ouroboros':
+                self.base_image = 'arcfirerumba/ouroboros'
+            else:
+                raise Exception('Only Ouroboros supported for now.')
+
+        img = self.base_image.rsplit(":", 1)
+
+        self.base_image_repo = img[0]
+        self.base_image_tag = "latest" if len(img) == 1 else img[1]
+        self.base_image = "%s:%s" % (self.base_image_repo, self.base_image_tag)
+
         # Pull image
         if self.pull_image:
                 docker_client.images.pull(self.base_image_repo,