fix crash on ShortHeader and other DNSException subclasses, fixes #247

nsupdate/main/dnstools.py

@@ -64,6 +64,7 @@ class FQDN(namedtuple('FQDN', ['host', 'domain'])):
 
 Timeout = dns.resolver.Timeout
 NoNameservers = dns.resolver.NoNameservers
+DNSException = dns.exception.DNSException
 
 
 class SameIpError(ValueError):

nsupdate/main/views.py

@@ -238,6 +238,8 @@ class AddHostView(CreateView):
             success, level, msg = False, messages.ERROR, 'Base domain does not exist.'
         except dnstools.SameIpError:
             success, level, msg = False, messages.ERROR, 'Host already exists in DNS.'
+        except dnstools.DNSException as e:
+            success, level, msg = False, messages.ERROR, 'DNSException [%s]' % str(e)
         except socket.error as err:
             success, level, msg = False, messages.ERROR, 'Communication to name server failed [%s]' % str(err)
         else: