openvpn: Upgrade to the new Debian way

Earlier only openvpn@.service file was available. Currently, Debian is using
openvpn-server@.service and openvpn-client@.service. Start using this and
upgrade our current users to this approach. This fixes the problem with
incorrect enabling/disabling of OpenVPN app in Plinth.

Tested primarily three cases:

- Install version 2 of the app directly. Make sure daemon runs,
  enabling/disabling the app works.

- Install version 1 of the app. Disable it. Upgrade to version 2 make sure
  everything is upgraded but disabled. Enabling make the app work properly.

- Install version 1 of the app. Enable it. Upgrade to version 2 make sure
  everything is upgraded, app is enabled and running.

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

actions/openvpn

@@ -32,7 +32,11 @@ KEYS_DIRECTORY = '/etc/openvpn/freedombox-keys'
 
 DH_KEY = '/etc/openvpn/freedombox-keys/dh4096.pem'
 
-SERVER_CONFIGURATION_PATH = '/etc/openvpn/freedombox.conf'
+OLD_SERVER_CONFIGURATION_PATH = '/etc/openvpn/freedombox.conf'
+SERVER_CONFIGURATION_PATH = '/etc/openvpn/server/freedombox.conf'
+
+OLD_SERVICE_NAME = 'openvpn@freedombox'
+SERVICE_NAME = 'openvpn-server@freedombox'
 
 CA_CERTIFICATE_PATH = KEYS_DIRECTORY + '/ca.crt'
 USER_CERTIFICATE_PATH = KEYS_DIRECTORY + '/{username}.crt'
@@ -99,6 +103,9 @@ def parse_arguments():
 
     subparsers.add_parser('is-setup', help='Return whether setup is completed')
     subparsers.add_parser('setup', help='Setup OpenVPN server configuration')
+    subparsers.add_parser(
+        'upgrade',
+        help='Upgrade OpenVPN server configuration from older configuration')
 
     get_profile = subparsers.add_parser(
         'get-profile', help='Return the OpenVPN profile of a user')
@@ -120,8 +127,21 @@ def subcommand_setup(_):
     _create_server_config()
     _create_certificates()
     _setup_firewall()
-    action_utils.service_enable('openvpn@freedombox')
+    action_utils.service_enable(SERVICE_NAME)
-    action_utils.service_restart('openvpn@freedombox')
+    action_utils.service_restart(SERVICE_NAME)
+
+
+def subcommand_upgrade(_):
+    """Upgrade from an older version if configured.
+
+    Otherwise do nothing.
+    """
+    if os.path.exists(OLD_SERVER_CONFIGURATION_PATH):
+        os.rename(OLD_SERVER_CONFIGURATION_PATH, SERVER_CONFIGURATION_PATH)
+
+    if action_utils.service_is_enabled(OLD_SERVICE_NAME):
+        action_utils.service_disable(OLD_SERVICE_NAME)
+        action_utils.service_enable(SERVICE_NAME)
 
 
 def _create_server_config():

plinth/modules/openvpn/__init__.py

@@ -30,12 +30,11 @@ from plinth import service as service_module
 from plinth.menu import main_menu
 from plinth.utils import format_lazy
 
-
+version = 2
-version = 1
 
 service = None
 
-managed_services = ['openvpn@freedombox']
+managed_services = ['openvpn-server@freedombox']
 
 managed_packages = ['openvpn', 'easy-rsa']
 
@@ -73,6 +72,7 @@ def init():
 def setup(helper, old_version=None):
     """Install and configure the module."""
     helper.install(managed_packages)
+    helper.call('post', actions.superuser_run, 'openvpn', ['upgrade'])
     global service
     if service is None:
         service = service_module.Service(