Print an error message for nonexistent gname

Also add support for all to be consistent with start/stop
Added a test for all

supervisor/supervisorctl.py

@@ -952,6 +952,24 @@ class DefaultControllerPlugin(ControllerPluginBase):
         added, changed, removed = result[0]
         valid_gnames = set(arg.strip().split())
 
+        # If all is specified treat it as if nothing was specified.
+        if "all" in valid_gnames:
+            valid_gnames = set()
+
+        # If any gnames are specified we need to verify that they are
+        # valid in order to print a useful error message.
+        if valid_gnames:
+            groups = set()
+            for info in supervisor.getAllProcessInfo():
+                groups.add(info['group'])
+            # New gnames would not currently exist in this set so
+            # add those as well.
+            groups.update(added)
+
+            for gname in valid_gnames:
+                if gname not in groups:
+                    self.ctl.output('ERROR: no such group: %s' % gname)
+
         for gname in removed:
             if valid_gnames and gname not in valid_gnames:
                 continue
@@ -984,7 +1002,8 @@ class DefaultControllerPlugin(ControllerPluginBase):
 
     def help_update(self):
         self.ctl.output("update\t\t\tReload config and add/remove as necessary")
-        self.ctl.output("update <gname> [...]\tUpdate a specific groups.")
+        self.ctl.output("update all\t\tReload config and add/remove as necessary")
+        self.ctl.output("update <gname> [...]\tUpdate specific groups")
 
     def _clearresult(self, result):
         name = result['name']

supervisor/tests/test_supervisorctl.py

@@ -783,6 +783,12 @@ class TestDefaultControllerPlugin(unittest.TestCase):
         self.assertEqual(sorted(supervisor.processes),
                          sorted(['changed', 'added1']))
 
+        supervisor.processes = ['changed', 'removed']
+        plugin.do_update('all')
+        self.assertEqual(sorted(supervisor.processes),
+                         sorted(['changed', 'added1', 'added2']))
+
+
     def test_update_changed_procs(self):
         from supervisor import xmlrpc