Bug #654025: nova-manage project zip and nova-manage vpn list broken by change in DB semantics when networks are missing

Catch exception.NotFound when getting project VPN data.  This is in two places:
nova-manage as part of its vpn list command, and
auth.manager.AuthManager.get_credentials.

Also, document the behaviour of db.api.project_get_network.

bin/nova-manage

@@ -88,11 +88,16 @@ class VpnCommands(object):
     def list(self):
         """Print a listing of the VPNs for all projects."""
         print "%-12s\t" % 'project',
-        print "%-12s\t" % 'ip:port',
+        print "%-20s\t" % 'ip:port',
         print "%s" % 'state'
         for project in self.manager.get_projects():
             print "%-12s\t" % project.name,
-            print "%s:%s\t" % (project.vpn_ip, project.vpn_port),
+
+            try:
+                s = "%s:%s" % (project.vpn_ip, project.vpn_port)
+            except exception.NotFound:
+                s = "None"
+            print "%-20s\t" % s,
 
             vpn = self._vpn_for(project.id)
             if vpn:

nova/auth/manager.py

@@ -653,7 +653,10 @@ class AuthManager(object):
         zippy.writestr(FLAGS.credential_key_file, private_key)
         zippy.writestr(FLAGS.credential_cert_file, signed_cert)
 
-        (vpn_ip, vpn_port) = self.get_project_vpn_data(project)
+        try:
+            (vpn_ip, vpn_port) = self.get_project_vpn_data(project)
+        except exception.NotFound:
+            vpn_ip = None
         if vpn_ip:
             configfile = open(FLAGS.vpn_client_template, "r")
             s = string.Template(configfile.read())