Add char field to set a password that is required to join the server

Reviewed-by: James Valleroy <jvalleroy@mailbox.org>
[james: Apply yapf formatting]
[james: Minor adjustment to help text]
Signed-off-by: James Valleroy <jvalleroy@mailbox.org>

actions/mumble

@@ -39,6 +39,10 @@ def parse_arguments():
     subparsers.add_parser('get-root-channel-name',
                           help='Print the root channel name')
 
+    subparser = subparsers.add_parser(
+        'change-join-password', help='Set the password to join the server')
+    subparser.add_argument('join_password', help='New join password')
+
     subparsers.required = True
     return parser.parse_args()
 
@@ -92,6 +96,14 @@ def subcommand_set_domain(arguments):
     domain_file.write_text(arguments.domain_name)
 
 
+def subcommand_change_join_password(arguments):
+    """Change to password that is required to join the server"""
+    aug = load_augeas()
+    aug.set('.anon/serverpassword', arguments.join_password)
+    aug.save()
+    action_utils.service_try_restart('mumble-server')
+
+
 def subcommand_change_root_channel_name(arguments):
     """Change the name of the Root channel."""
     aug = load_augeas()

plinth/modules/mumble/forms.py

@@ -35,6 +35,15 @@ class MumbleForm(forms.Form):
         required=False,
     )
 
+    join_password = forms.CharField(
+        max_length=32,
+        label=_('Set a password to join the server'),
+        widget=forms.PasswordInput,
+        help_text=_('Set a password that is required to join the server. '
+                    'Leave empty to use the current password.'),
+        required=False,
+    )
+
     root_channel_name = forms.CharField(
         label=_('Set the name for the root channel'),
         min_length=1,

plinth/modules/mumble/views.py

@@ -39,6 +39,12 @@ class MumbleAppView(AppView):
             messages.success(self.request,
                              _('SuperUser password successfully updated.'))
 
+        join_password = new_config.get('join_password')
+        if join_password:
+            actions.superuser_run('mumble',
+                                  ['change-join-password', join_password])
+            messages.success(self.request, _('Join password changed'))
+
         name = new_config.get('root_channel_name')
         if name:
             actions.superuser_run('mumble', ['change-root-channel-name', name])