checkpoint: make python example accept multiple devices and timeout

Add a timeout parameter and allow passing multiple interfaces to make
the script more useful for testing purposes.

examples/python/dbus/checkpoint.py

@@ -20,36 +20,48 @@
 
 import dbus, sys
 
-# This example takes a device interface name as a parameter and tells
+# This example takes a list of device interface names as a parameter
-# NetworkManager to disconnect that device, closing down any network
+# and tells NetworkManager to create a checkpoint on those devices. It
-# connection it may have
+# is then possible to restore or destroy the checkpoint.
-
-if len(sys.argv) != 2:
-    raise Exception("Usage: %s <interface>" % sys.argv[0])
-
-bus = dbus.SystemBus()
 
 # Get a proxy for the base NetworkManager object
+bus = dbus.SystemBus()
 proxy = bus.get_object("org.freedesktop.NetworkManager", "/org/freedesktop/NetworkManager")
 manager = dbus.Interface(proxy, "org.freedesktop.NetworkManager")
+allDevs = manager.GetDevices()
 
-dpath = None
+def Usage():
+    print "Usage: %s <ROLLBACK-INTERVAL> [INTERFACE]..." % sys.argv[0]
+    sys.exit(1)
 
-# Find the device
+def GetDevicePath(ifname):
-devices = manager.GetDevices()
+    for dev in allDevs:
-for d in devices:
+        dev_proxy = bus.get_object("org.freedesktop.NetworkManager", dev)
-    dev_proxy = bus.get_object("org.freedesktop.NetworkManager", d)
         prop_iface = dbus.Interface(dev_proxy, "org.freedesktop.DBus.Properties")
-    iface = prop_iface.Get("org.freedesktop.NetworkManager.Device", "Interface")
+        interface = prop_iface.Get("org.freedesktop.NetworkManager.Device", "Interface")
-    if iface == sys.argv[1]:
+        if interface == ifname:
-        dpath = d
+            return dev
-        break
+    return
 
-if not dpath or not len(dpath):
+if len(sys.argv) < 2:
-    raise Exception("NetworkManager knows nothing about %s" % sys.argv[1])
+    Usage()
 
-checkpoint = manager.CheckpointCreate([ dpath ],
+try:
-                                      0,  # no rollback
+    interval = int(sys.argv[1])
+except ValueError:
+    Usage()
+
+devList = []
+
+for arg in sys.argv[2:]:
+    path = GetDevicePath(arg)
+    if path == None:
+        raise Exception("NetworkManager knows nothing about %s" % arg)
+    else:
+        devList.append(path)
+
+checkpoint = manager.CheckpointCreate(devList,
+                                      interval,
                                       1); # DESTROY_ALL
 
 choice = raw_input('Do you want to rollback [y/n]? ').lower()