fix potential TypeError

diff --git a/sfa/rspecs/elements/versions/pgv2Interface.py b/sfa/rspecs/elements/versions/pgv2Interface.py
index 1c16e97..2984591 100644 (file)
--- a/sfa/rspecs/elements/versions/pgv2Interface.py
+++ b/sfa/rspecs/elements/versions/pgv2Interface.py
@@ -6,13 +6,14 @@ class PGv2Interface:
 
     @staticmethod
     def add_interfaces(xml, interfaces):
-        for interface in interfaces:
-            if_elem = xml.add_instance('interface', interface, ['component_id', 'client_id'])
-            ips = interface.get('ips', [])
-            for ip in ips:
-                if_elem.add_instance('ip', {'address': ip.get('address'),
-                                            'netmask': ip.get('netmask'),
-                                            'type': ip.get('type')}) 
+        if isinstance(interfaces, list):
+            for interface in interfaces:
+                if_elem = xml.add_instance('interface', interface, ['component_id', 'client_id'])
+                ips = interface.get('ips', [])
+                for ip in ips:
+                    if_elem.add_instance('ip', {'address': ip.get('address'),
+                                                'netmask': ip.get('netmask'),
+                                                'type': ip.get('type')}) 
     
     @staticmethod
     def get_interfaces(xml):