transmission: Simplify actions using the privileged decorator

Tests:

- Get and set the storage path.

- Functional tests pass.

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

actions/transmission

@@ -1,63 +0,0 @@
-#!/usr/bin/python3
-# SPDX-License-Identifier: AGPL-3.0-or-later
-"""
-Configuration helper for Transmission daemon.
-"""
-
-import argparse
-import json
-import sys
-
-from plinth import action_utils
-
-TRANSMISSION_CONFIG = '/etc/transmission-daemon/settings.json'
-
-
-def parse_arguments():
-    """Return parsed command line arguments as dictionary."""
-    parser = argparse.ArgumentParser()
-    subparsers = parser.add_subparsers(dest='subcommand', help='Sub command')
-
-    subparsers.add_parser('get-configuration',
-                          help='Return the current configuration')
-    subparsers.add_parser(
-        'merge-configuration',
-        help='Merge JSON configuration from stdin with existing')
-
-    subparsers.required = True
-    return parser.parse_args()
-
-
-def subcommand_get_configuration(_):
-    """Return the current configuration in JSON format."""
-    configuration = open(TRANSMISSION_CONFIG, 'r').read()
-    print(configuration)
-
-
-def subcommand_merge_configuration(arguments):
-    """Merge given JSON configuration with existing configuration."""
-    configuration = sys.stdin.read()
-    configuration = json.loads(configuration)
-
-    current_configuration = open(TRANSMISSION_CONFIG, 'r').read()
-    current_configuration = json.loads(current_configuration)
-
-    new_configuration = current_configuration
-    new_configuration.update(configuration)
-    new_configuration = json.dumps(new_configuration, indent=4, sort_keys=True)
-
-    open(TRANSMISSION_CONFIG, 'w').write(new_configuration)
-    action_utils.service_reload('transmission-daemon')
-
-
-def main():
-    """Parse arguments and perform all duties."""
-    arguments = parse_arguments()
-
-    subcommand = arguments.subcommand.replace('-', '_')
-    subcommand_method = globals()['subcommand_' + subcommand]
-    subcommand_method(arguments)
-
-
-if __name__ == '__main__':
-    main()

plinth/modules/transmission/__init__.py

@@ -3,12 +3,9 @@
 FreedomBox app to configure Transmission server.
 """
 
-import json
-
 from django.urls import reverse_lazy
 from django.utils.translation import gettext_lazy as _
 
-from plinth import actions
 from plinth import app as app_module
 from plinth import cfg, frontpage, menu
 from plinth.daemon import Daemon
@@ -20,7 +17,7 @@ from plinth.modules.users.components import UsersAndGroups
 from plinth.package import Packages
 from plinth.utils import format_lazy
 
-from . import manifest
+from . import manifest, privileged
 
 _description = [
     _('Transmission is a BitTorrent client with a web interface.'),
@@ -130,8 +127,6 @@ def setup(helper, old_version=None):
         'rpc-whitelist-enabled': False,
         'rpc-authentication-required': False
     }
-    helper.call('post', actions.superuser_run, 'transmission',
-                ['merge-configuration'],
-                input=json.dumps(new_configuration).encode())
+    helper.call('post', privileged.merge_configuration, new_configuration)
     add_user_to_share_group(SYSTEM_USER, TransmissionApp.DAEMON)
     helper.call('post', app.enable)

plinth/modules/transmission/privileged.py

@@ -0,0 +1,33 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+"""
+Configuration helper for Transmission daemon.
+"""
+
+import json
+import pathlib
+from typing import Union
+
+from plinth import action_utils
+from plinth.actions import privileged
+
+_transmission_config = pathlib.Path('/etc/transmission-daemon/settings.json')
+
+
+@privileged
+def get_configuration() -> dict[str, str]:
+    """Return the current configuration in JSON format."""
+    return json.loads(_transmission_config.read_text(encoding='utf-8'))
+
+
+@privileged
+def merge_configuration(configuration: dict[str, Union[str, bool]]) -> None:
+    """Merge given JSON configuration with existing configuration."""
+    current_configuration = _transmission_config.read_bytes()
+    current_configuration = json.loads(current_configuration)
+
+    new_configuration = current_configuration
+    new_configuration.update(configuration)
+    new_configuration = json.dumps(new_configuration, indent=4, sort_keys=True)
+
+    _transmission_config.write_text(new_configuration, encoding='utf-8')
+    action_utils.service_reload('transmission-daemon')

plinth/modules/transmission/views.py

@@ -3,15 +3,15 @@
 FreedomBox app for configuring Transmission Server.
 """
 
-import json
 import logging
 import socket
 
 from django.contrib import messages
 from django.utils.translation import gettext as _
 
-from plinth import actions, views
+from plinth import views
 
+from . import privileged
 from .forms import TransmissionForm
 
 logger = logging.getLogger(__name__)
@@ -25,9 +25,7 @@ class TransmissionAppView(views.AppView):
     def get_initial(self):
         """Get the current settings from Transmission server."""
         status = super().get_initial()
-        configuration = actions.superuser_run('transmission',
-                                              ['get-configuration'])
-        configuration = json.loads(configuration)
+        configuration = privileged.get_configuration()
         status['storage_path'] = configuration['download-dir']
         status['hostname'] = socket.gethostname()
 
@@ -41,9 +39,7 @@ class TransmissionAppView(views.AppView):
             new_configuration = {
                 'download-dir': new_status['storage_path'],
             }
-
-            actions.superuser_run('transmission', ['merge-configuration'],
-                                  input=json.dumps(new_configuration).encode())
+            privileged.merge_configuration(new_configuration)
             messages.success(self.request, _('Configuration updated'))
 
         return super().form_valid(form)