added more documentation comments
diff --git a/emuvim/api/zerorpcapi.py b/emuvim/api/zerorpcapi.py
index 7be3f60..71505a5 100644
--- a/emuvim/api/zerorpcapi.py
+++ b/emuvim/api/zerorpcapi.py
@@ -11,6 +11,14 @@
class ZeroRpcApiEndpoint(object):
+ """
+ Simple API endpoint that offers a zerorpc-based
+ interface. This interface will be used by the
+ default command line client.
+ It can be used as a reference to implement
+ REST interfaces providing the same semantics,
+ like e.g. OpenStack compute API.
+ """
def __init__(self, listenip, port):
self.dcs = {}
@@ -38,12 +46,18 @@
class MultiDatacenterApi(object):
+ """
+ Just pass through the corresponding request to the
+ selected data center. Do not implement provisioning
+ logic here because will will have multiple API
+ endpoint implementations at the end.
+ """
def __init__(self, dcs):
self.dcs = dcs
def compute_action_start(self, dc_name, compute_name):
- # TODO return UUID / IP ?
+ # TODO what to return UUID / IP ?
logging.debug("RPC CALL: compute start")
if dc_name in self.dcs:
self.dcs[dc_name].addCompute(compute_name)
diff --git a/emuvim/cli/__main__.py b/emuvim/cli/__main__.py
index 95ce01e..4c55916 100644
--- a/emuvim/cli/__main__.py
+++ b/emuvim/cli/__main__.py
@@ -1,6 +1,11 @@
"""
For now only a dummy client. Connects to the zerorpc interface of the
emulator and performs some actions (start/stop/list).
+
+ We will provide a full CLI here later on which looks like:
+
+ cli compute start dc1 my_name flavor_a
+ cli network create dc1 11.0.0.0/24
"""
import time
import zerorpc
diff --git a/emuvim/dcemulator/net.py b/emuvim/dcemulator/net.py
index 586b1e8..e0f41e2 100644
--- a/emuvim/dcemulator/net.py
+++ b/emuvim/dcemulator/net.py
@@ -14,6 +14,12 @@
class DCNetwork(object):
+ """
+ Wraps the original Mininet class and provides
+ methods to add data centers, switches, etc.
+
+ This class is used by topology definition scripts.
+ """
def __init__(self):
self.dcs = {}
@@ -85,4 +91,3 @@
def CLI(self):
CLI(self.mnet)
-
diff --git a/emuvim/dcemulator/node.py b/emuvim/dcemulator/node.py
index 3111735..5e5def0 100644
--- a/emuvim/dcemulator/node.py
+++ b/emuvim/dcemulator/node.py
@@ -12,6 +12,8 @@
"""
Represents a logical data center to which compute resources
(Docker containers) can be added at runtime.
+
+ Will also implement resource bookkeeping in later versions.
"""
def __init__(self, name):
@@ -40,6 +42,10 @@
pass
def addCompute(self, name):
+ """
+ Create a new container as compute resource and connect it to this
+ data center.
+ """
#TODO remove mnet shortcut to have a clean API
#TODO connect container to DC's swtich
self.net.mnet.addDocker("%s.%s" % (self.name, name), dimage="ubuntu")
diff --git a/emuvim/example_topology.py b/emuvim/example_topology.py
index a21cdba..fce0698 100644
--- a/emuvim/example_topology.py
+++ b/emuvim/example_topology.py
@@ -2,6 +2,17 @@
This is an example topology for the distributed cloud emulator (dcemulator).
(c) 2015 by Manuel Peuster <manuel.peuster@upb.de>
+
+This is an example that shows how a user of the emulation tool can
+define network topologies with multiple emulated cloud data centers.
+
+The definition is done with a Python API which looks very similar to the
+Mininet API (in fact it is a wrapper for it).
+
+We only specify the topology *between* data centers not within a single
+data center (data center internal setups or placements are not of interest,
+we want to experiment with VNF chains deployed across multiple PoPs).
+
The original Mininet API has to be completely hidden and not be used by this
script.
"""
@@ -13,40 +24,80 @@
def create_topology1():
- # TODO add long comments to this example to show people how to use this
- # initialize network
+ """
+ 1. Create a data center network object (DCNetwork)
+ """
net = DCNetwork()
- # add data centers
+ """
+ 2. Add (logical) data centers to the topology
+ (each data center is one "bigswitch" in our simplified
+ first prototype)
+ """
dc1 = net.addDatacenter("dc1")
dc2 = net.addDatacenter("dc2")
dc3 = net.addDatacenter("dc3")
dc4 = net.addDatacenter("dc4")
- # add additional SDN switches to our topology
+
+ """
+ 3. You can add additional SDN switches for data center
+ interconnections to the network.
+ """
s1 = net.addSwitch("s1")
- # add links between data centers
+
+ """
+ 4. Add links between your data centers and additional switches
+ to define you topology.
+ These links can use Mininet's features to limit bw, add delay or jitter.
+ """
net.addLink(dc1, dc2)
net.addLink("dc1", s1)
net.addLink(s1, "dc3")
net.addLink(s1, dc4)
- # create and start APIs (to access emulated cloud data centers)
+ """
+ 5. We want to access and control our data centers from the outside,
+ e.g., we want to connect an orchestrate to start/stop compute
+ resources aka. VNFs (represented by Docker containers in the emulated)
+
+ So we need to instantiate API endpoints (e.g. a zerorpc or REST
+ interface). Depending on the endpoint implementations, we can connect
+ one or more data centers to it, which can then be controlled through
+ this API, e.g., start/stop/list compute instances.
+ """
+ # create a new instance of a endpoint implementation
zapi1 = ZeroRpcApiEndpoint("0.0.0.0", 4242)
+ # connect data centers to this endpoint
zapi1.connectDatacenter(dc1)
zapi1.connectDatacenter(dc2)
+ # run API endpoint server (in another thread, don't block)
zapi1.start()
- # lets also create a second API endpoint on another port to
- # demonstrate hat you can have one endpoint for each of
- # your data centers
+
+ """
+ 5.1. For our example, we create a second endpoint to illustrate that
+ this is support by our design. This feature allows us to have
+ one API endpoint for each data center. This makes the emulation
+ environment more realistic because you can easily create one
+ OpenStack-like REST API endpoint for *each* data center.
+ This will look like a real-world multi PoP/data center deployment
+ from the perspective of an orchestrator.
+ """
zapi2 = ZeroRpcApiEndpoint("0.0.0.0", 4343)
zapi2.connectDatacenter(dc3)
zapi2.connectDatacenter(dc4)
zapi2.start()
- # start network
+ """
+ 6. Finally we are done and can start our network (the emulator).
+ We can also enter the Mininet CLI to interactively interact
+ with our compute resources (just like in default Mininet).
+ But we can also implement fully automated experiments that
+ can be executed again and again.
+ """
net.start()
- net.CLI() # TODO remove this when we integrate APIs?
- net.stop() # TODO remove this when we integrate APIs?
+ net.CLI()
+ # when the user types exit in the CLI, we stop the emulator
+ net.stop()
def main():