Report an error that carries no message of its own

nodereseat printed "Error: " and nothing else against a bmc that refused the
credentials. The redfish plugin reports it properly, but the message it emits
re-raises TargetEndpointBadCredentials with no arguments when a single node is
addressed, and the enclosure plugin renders that with str(e), which is empty.

Both hardwaremanagement plugins already had a helper for exactly this, one copy
each. Keep one in confluent.exceptions instead, teach it to fall back to the
description a confluent exception carries by class before falling back to the
exception name, and use it in the enclosure plugin too.

get_error_body had the mirror image of the same bug, joining the class
description and the message unconditionally and so answering "Bad Credentials -"
with a separator and nothing after it. The apierrorstr property beside it
already gets this right, so use it.

confluent_server/confluent/exceptions.py

@@ -19,6 +19,19 @@ import base64
 import json
 import msgpack
 
+def exc_text(theexc):
+    """Render an exception for a user, even when it carries no message.
+
+    An error with no text at all tells the user nothing, so fall back to the
+    description a confluent exception carries by class, and then to the name of
+    the exception.
+    """
+    text = str(theexc)
+    if text and text != 'None':
+        return text
+    return getattr(theexc, '_apierrorstr', None) or type(theexc).__name__
+
+
 def deserialize_exc(msg):
     excd = msgpack.unpackb(msg, raw=False)
     if excd[0] == 'Exception':
@@ -35,8 +48,7 @@ class ConfluentException(Exception):
     _apierrorstr = 'Unexpected Error'
 
     def get_error_body(self):
-        errstr = ' - '.join((self._apierrorstr, str(self)))
-        return json.dumps({'error': errstr })
+        return json.dumps({'error': self.apierrorstr})
 
     def serialize(self):
         return msgpack.packb([self.__class__.__name__, [str(self)]],

confluent_server/confluent/plugins/hardwaremanagement/enclosure.py

@@ -29,11 +29,11 @@ async def reseat_bays(encmgr, bays, configmanager, rspq):
                         inputdata={'reseat': encbay}):
                     await rspq.put(rsp)
             except pygexc.UnsupportedFunctionality as uf:
-                await rspq.put(msg.ConfluentNodeError(node, str(uf)))
+                await rspq.put(msg.ConfluentNodeError(node, exc.exc_text(uf)))
             except exc.TargetEndpointUnreachable as uf:
-                await rspq.put(msg.ConfluentNodeError(node, str(uf)))
+                await rspq.put(msg.ConfluentNodeError(node, exc.exc_text(uf)))
             except Exception as e:
-                await rspq.put(msg.ConfluentNodeError(node, str(e)))
+                await rspq.put(msg.ConfluentNodeError(node, exc.exc_text(e)))
     finally:
         await rspq.put(None)
 

confluent_server/confluent/plugins/hardwaremanagement/ipmi.py

@@ -15,6 +15,7 @@
 
 import asyncio
 import confluent.exceptions as exc
+from confluent.exceptions import exc_text
 import confluent.firmwaremanager as firmwaremanager
 import confluent.interface.console as conapi
 import confluent.messages as msg
@@ -284,18 +285,6 @@ def _donothing(data):
     pass
 
 
-def exc_text(theexc):
-    """Render an exception for a user, even when it carries no message.
-
-    An error with no text at all tells the user nothing, so name the exception
-    when that is all we have.
-    """
-    text = str(theexc)
-    if not text or text == 'None':
-        return type(theexc).__name__
-    return text
-
-
 class IpmiConsole(conapi.Console):
     configattributes = frozenset(_configattributes)
     bmctonodemapping = {}

confluent_server/confluent/plugins/hardwaremanagement/redfish.py

@@ -17,6 +17,7 @@ import json
 import asyncio
 import confluent.vinzmanager as vinzmanager
 import confluent.exceptions as exc
+from confluent.exceptions import exc_text
 import confluent.firmwaremanager as firmwaremanager
 import confluent.messages as msg
 import confluent.util as util
@@ -272,18 +273,6 @@ def _donothing(data):
     pass
 
 
-def exc_text(theexc):
-    """Render an exception for a user, even when it carries no message.
-
-    An error with no text at all tells the user nothing, so name the exception
-    when that is all we have.
-    """
-    text = str(theexc)
-    if not text or text == 'None':
-        return type(theexc).__name__
-    return text
-
-
 async def perform_requests(operator, nodes, element, cfg, inputdata, realop):
     cryptit = cfg.decrypt
     cfg.decrypt = True