Make sure we just the "instance" kwarg in cloud.action.

Fixes #29602

salt/cloud/__init__.py

@@ -469,16 +469,28 @@ class CloudClient(object):
             )
         '''
         mapper = salt.cloud.Map(self._opts_defaults(action=fun, names=names))
+        if instance:
+            if names:
+                raise SaltCloudConfigError(
+                    'Please specify either a list of \'names\' or a single '
+                    '\'instance\', but not both.'
+                )
+            names = [instance]
+
         if names and not provider:
             self.opts['action'] = fun
             return mapper.do_action(names, kwargs)
-        if provider:
+
+        if provider and not names:
             return mapper.do_function(provider, fun, kwargs)
         else:
             # This should not be called without either an instance or a
-            # provider.
+            # provider. If both an instance/list of names and a provider
+            # are given, then we also need to exit. We can only have one
+            # or the other.
             raise SaltCloudConfigError(
-                'Either an instance or a provider must be specified.'
+                'Either an instance (or list of names) or a provider must be '
+                'specified, but not both.'
             )
 
 

salt/runners/cloud.py

@@ -6,13 +6,18 @@ The Salt Cloud Runner
 This runner wraps the functionality of salt cloud making salt cloud routines
 available to all internal apis via the runner system
 '''
-from __future__ import absolute_import
 
 # Import python libs
+from __future__ import absolute_import
+import logging
 import os
 
 # Import Salt libs
 import salt.cloud
+from salt.exceptions import SaltCloudConfigError
+
+# Get logging started
+log = logging.getLogger(__name__)
 
 
 def _get_client():
@@ -136,12 +141,17 @@ def action(*args, **kwargs):
         salt-run cloud.actions start my-salt-vm
     '''
     client = _get_client()
-    info = client.action(args[0],
-                         kwargs.get('cloudmap', None),
-                         args[1:],
-                         kwargs.get('provider', None),
-                         kwargs.get('instance', None),
-                         kwargs)
+    try:
+        info = client.action(args[0],
+                             kwargs.get('cloudmap', None),
+                             args[1:],
+                             kwargs.get('provider', None),
+                             kwargs.get('instance', None),
+                             kwargs)
+    except SaltCloudConfigError as err:
+        log.error(err)
+        return {}
+
     return info