more error checking and better exception hygiene

lithoxyl/actors.py

@@ -36,6 +36,8 @@ def __init__(self, task, interval=DEFAULT_INTERVAL, **kwargs):
         self.max_interval = float(max_interval or interval * 8)
         self._daemonize_thread = kwargs.pop('daemonize_thread', True)
         self._note = kwargs.pop('note', None)
+        if not callable(self._note):
+            raise ValueError('expected callable for note, not %r' % self._note)
         if kwargs:
             raise TypeError('unexpected keyword arguments: %r' % kwargs.keys())
 

lithoxyl/ewma.py

@@ -15,8 +15,8 @@ def __init__(self, periods=None, interval=None):
         "Takes an iterable of periods and an update interval, both in seconds."
         self._interval = float(interval or DEFAULT_INTERVAL)
         if not self._interval > 0:
-            raise TypeError('interval must be greater than 0, not: %r'
-                            % self._interval)
+            raise ValueError('interval must be greater than 0, not: %r'
+                             % self._interval)
 
         periods = periods or DEFAULT_PERIODS
         self._rate_map = dict([(p, None) for p in periods])

lithoxyl/record.py

@@ -100,10 +100,7 @@ def __repr__(self):
 
     @property
     def level_name(self):
-        try:
-            return self.level.name
-        except Exception:
-            return repr(self.level)
+        return self.level.name
 
     @property
     def status(self):
@@ -117,7 +114,7 @@ def duration(self):
         try:
             return self.complete_record.ctime - self.begin_record.ctime
         except Exception:
-            return 0
+            return 0.0
 
     def begin(self, message=None, *a, **kw):
         self.data_map.update(kw)