implement BaseMessage.__repr__

Take advantage of the information contained in signature/parameter
objects to represent positional and keyword arguments properly. Fall
back to using the funcsigs module on Python 2.

requirements.txt

@@ -11,3 +11,4 @@ Flask-Script
 Flask-SQLAlchemy
 Flask-Migrate
 python-fedora
+funcsigs # Python2 only

rida/messaging.py

@@ -25,6 +25,11 @@
 """Generic messaging functions."""
 
 import re
+try:
+    from inspect import signature
+except ImportError:
+    from funcsigs import signature
+
 from rida import logger
 
 
@@ -36,6 +41,17 @@ class BaseMessage(object):
         """
         self.msg_id = msg_id
 
+    def __repr__(self):
+        init_sig = signature(self.__init__)
+
+        args_strs = (
+            "{}={!r}".format(name, getattr(self, name))
+            if param.default != param.empty
+            else repr(getattr(self, name))
+            for name, param in init_sig.parameters.items())
+
+        return "{}({})".format(type(self).__name__, ', '.join(args_strs))
+
     @staticmethod
     def from_fedmsg(topic, msg):
         """