Merge pull request #12 from sperrygrove/exception_hierarchy

Adds RtError super class

rt.py

@@ -53,46 +53,51 @@ from six.moves import range
 DEFAULT_QUEUE = 'General'
 """ Default queue used. """
 
-class AuthorizationError(Exception):
+class RtError(Exception):
+    """ Super class of all Rt Errors """
+
+    pass
+
+class AuthorizationError(RtError):
     """ Exception raised when module cannot access :term:`API` due to invalid
     or missing credentials. """
 
     pass
 
-class NotAllowed(Exception):
+class NotAllowed(RtError):
     """ Exception raised when request cannot be finished due to
     insufficient privileges. """
 
     pass
 
-class UnexpectedResponse(Exception):
+class UnexpectedResponse(RtError):
     """ Exception raised when unexpected HTTP code is received. """
 
     pass
 
-class UnexpectedMessageFormat(Exception):
+class UnexpectedMessageFormat(RtError):
     """ Exception raised when response has bad status code (not the HTTP code,
     but code in the first line of the body as 200 in `RT/4.0.7 200 Ok`)
     or message parsing fails because of unexpected format. """
 
     pass
 
-class APISyntaxError(Exception):
+class APISyntaxError(RtError):
     """ Exception raised when syntax error is received. """
 
     pass
 
-class InvalidUse(Exception):
+class InvalidUse(RtError):
     """ Exception raised when API method is not used correctly. """
 
     pass
 
-class BadRequest(Exception):
+class BadRequest(RtError):
     """ Exception raised when HTTP code 400 (Bad Request) is received. """
 
     pass
 
-class ConnectionError(Exception):
+class ConnectionError(RtError):
     """ Encapsulation of various exceptions indicating network problems. """
 
     def __init__(self, message, cause):
@@ -104,7 +109,7 @@ class ConnectionError(Exception):
         super(ConnectionError, self).__init__(message + ' (Caused by ' + repr(cause) + ")")
         self.cause = cause
 
-class InvalidQueryError(Exception):
+class InvalidQueryError(RtError):
     """ Exception raised when attempting to search RT with an invalid raw query. """
 
     pass