Raise exception if no session is created

If the clientmanager is unable to create a keystone session (due to
insufficient auth parameters or something else) then the exception
caused by this shouldn't be ignored, as was the case.

On the other hand, we don't want this behaviour in the case of the
'complete' command, so this is now properly detected.

Change-Id: If4f453d23cc87900cda752e9ffbcf41ded59e26f
Closes-Bug: #1444640

Author: Juan Antonio Osorio Robles

openstackclient/shell.py

@@ -24,6 +24,7 @@
 
 from cliff import app
 from cliff import command
+from cliff import complete
 from cliff import help
 
 import openstackclient
@@ -76,6 +77,7 @@ def __init__(self):
 
         # Some commands do not need authentication
         help.HelpCommand.auth_required = False
+        complete.CompleteCommand.auth_required = False
 
         super(OpenStackShell, self).__init__(
             description=__doc__.strip(),
@@ -318,12 +320,8 @@ def prepare_to_run_command(self, cmd):
             cmd.__class__.__name__,
         )
         if cmd.auth_required:
-            try:
-                # Trigger the Identity client to initialize
-                self.client_manager.auth_ref
-            except Exception as e:
-                self.log.warning("Possible error authenticating: " + str(e))
-                pass
+            # Trigger the Identity client to initialize
+            self.client_manager.auth_ref
         return
 
     def clean_up(self, cmd, result, err):