Improve exception logging in context functions

Observing programming errors happening within the `is_filtered`,
`get_topic_data`, and `get_all_data` functions, and their callees, was
painful. Let's be more verbose now.

CHANGES.rst

@@ -7,6 +7,8 @@ in progress
 ===========
 
 - Fix: Don't crash when receiving non-UTF8 payloads. Thanks, @sevmonster.
+- Improve exception logging in ``is_filtered``, ``get_topic_data``, and
+  ``get_all_data`` context functions. Thanks, @sevmonster.
 
 
 2023-04-11 0.33.0

mqttwarn/context.py

@@ -62,7 +62,7 @@ def is_filtered(self, section, topic, payload):
             try:
                 return self.invoker.filter(filterfunc, topic, payload, section)
             except Exception as e:
-                logger.warning("Cannot invoke filter function '%s' defined in '%s': %s" % (filterfunc, section, e))
+                logger.exception("Cannot invoke filter function '%s' defined in '%s': %s" % (filterfunc, section, e))
         return False
 
     def get_topic_data(self, section, topic):
@@ -71,7 +71,7 @@ def get_topic_data(self, section, topic):
             try:
                 return self.invoker.datamap(name, topic)
             except Exception as e:
-                logger.warning("Cannot invoke datamap function '%s' defined in '%s': %s" % (name, section, e))
+                logger.exception("Cannot invoke datamap function '%s' defined in '%s': %s" % (name, section, e))
         return None
 
     def get_all_data(self, section, topic, data):
@@ -80,7 +80,7 @@ def get_all_data(self, section, topic, data):
             try:
                 return self.invoker.alldata(name, topic, data)
             except Exception as e:
-                logger.warning("Cannot invoke alldata function '%s' defined in '%s': %s" % (name, section, e))
+                logger.exception("Cannot invoke alldata function '%s' defined in '%s': %s" % (name, section, e))
         return None
 
     def get_topic_targets(self, section, topic, data):