email_server: action: Refactor for simplicity

- Parse arguments in a readable way.

- Convert decorator into simple call.

- Make a simple call instead of looking for subcommand.

- Don't setup logging in global scope.

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

actions/email_server

@@ -1,5 +1,8 @@
 #!/usr/bin/python3
 # SPDX-License-Identifier: AGPL-3.0-or-later
+"""
+Configuration helper for email server.
+"""
 
 import argparse
 import logging
@@ -7,50 +10,39 @@ import os
 import sys
 
 import plinth.log
+from plinth.modules.email_server import audit
 
 EXIT_SYNTAX = 10
 EXIT_PERM = 20
 
-# Set up logging
-plinth.log.pipe_to_syslog(to_stderr='tty')
 logger = logging.getLogger(os.path.basename(__file__))
 
 
-def reserved_for_root(fun):
-    def wrapped(*args, **kwargs):
-        if os.getuid() != 0:
-            logger.critical('This action is reserved for root')
-            sys.exit(EXIT_PERM)
-        return fun(*args, **kwargs)
-    return wrapped
-
-
 def main():
-    if not sys.stdin.isatty():
-        print('WARNING: Output will not be shown. Check syslog for logs',
-              file=sys.stderr)
+    """Parse arguments."""
+    # Set up logging
+    plinth.log.pipe_to_syslog(to_stderr='tty')
 
     parser = argparse.ArgumentParser()
-    group = parser.add_mutually_exclusive_group(required=True)
-    group.add_argument('-i', nargs='+', dest='ipc')
+    parser.add_argument('module', help='Module to trigger action in')
+    parser.add_argument('action', help='Action to trigger in module')
+    parser.add_argument('arguments', help='String arguments for action',
+                        nargs='*')
+    args = parser.parse_args()
 
-    # Select the first non-empty dict item
-    adict = vars(parser.parse_args())
-    generator = (kv for kv in adict.items() if kv[1] is not None)
-    subcommand, arguments = next(generator)
-
-    function = globals()['subcommand_' + subcommand]
     try:
-        function(*arguments)
-    except Exception as e:
-        logger.exception(e)
+        _call(args.module, args.action, args.arguments)
+    except Exception as exception:
+        logger.exception(exception)
         _log_additional_info()
         sys.exit(1)
 
 
-@reserved_for_root
-def subcommand_ipc(module_name, action_name, *args):
-    import plinth.modules.email_server.audit as audit
+def _call(module_name, action_name, arguments):
+    """Import the module and run action as superuser."""
+    if os.getuid() != 0:
+        logger.critical('This action is reserved for root')
+        sys.exit(EXIT_PERM)
 
     # We only run actions defined in the audit module
     if module_name not in audit.__all__:
@@ -58,15 +50,17 @@ def subcommand_ipc(module_name, action_name, *args):
         sys.exit(EXIT_SYNTAX)
 
     module = getattr(audit, module_name)
-    function = getattr(module, 'action_' + action_name, None)
-    if function is None:
+    try:
+        action = getattr(module, 'action_' + action_name)
+    except AttributeError:
         logger.critical('Bad action: %s/%r', module_name, action_name)
         sys.exit(EXIT_SYNTAX)
 
-    function(*args)
+    action(*arguments)
 
 
 def _log_additional_info():
+    """Log additional debugging information."""
     import grp
     import pwd
     resu = ','.join(pwd.getpwuid(uid).pw_name for uid in os.getresuid())

plinth/modules/email_server/aliases.py

@@ -98,7 +98,7 @@ def _set_status(uid, aliases, status):
 
 def first_setup():
     """Create the database file and schema inside it."""
-    actions.superuser_run('email_server', ['-i', 'aliases', 'setup'])
+    actions.superuser_run('email_server', ['aliases', 'setup'])
 
     # Create schema if not exists
     query = '''

plinth/modules/email_server/audit/domain.py

@@ -42,14 +42,14 @@ def get():
 
 
 def repair():
-    superuser_run('email_server', ['-i', 'domain', 'set_up'])
+    superuser_run('email_server', ['domain', 'set_up'])
 
 
 def repair_component(action_name):
     allowed_actions = {'set_up': ['postfix']}
     if action_name not in allowed_actions:
         return
-    superuser_run('email_server', ['-i', 'domain', action_name])
+    superuser_run('email_server', ['domain', action_name])
     return allowed_actions[action_name]
 
 
@@ -199,7 +199,7 @@ def set_keys(raw):
         raise ClientError('POST data exceeds max line length')
 
     try:
-        superuser_run('email_server', ['-i', 'domain', 'set_keys'], input=ipc)
+        superuser_run('email_server', ['domain', 'set_keys'], input=ipc)
     except ActionError as e:
         stdout = e.args[1]
         if not stdout.startswith('ClientError:'):

plinth/modules/email_server/audit/home.py

@@ -49,8 +49,7 @@ def put_uid(uid_number):
 
 def _put(arg_type, user_info):
     try:
-        args = ['-i', 'home', 'mk', arg_type, user_info]
-        superuser_run('email_server', args)
+        superuser_run('email_server', ['home', 'mk', arg_type, user_info])
     except ActionError as e:
         raise RuntimeError('Action script failure') from e
 

plinth/modules/email_server/audit/ldap.py

@@ -86,7 +86,7 @@ def repair():
     POST /audit/ldap/repair
     """
     aliases.first_setup()
-    actions.superuser_run('email_server', ['-i', 'ldap', 'set_up'])
+    actions.superuser_run('email_server', ['ldap', 'set_up'])
 
 
 def action_set_up():

plinth/modules/email_server/audit/rcube.py

@@ -32,7 +32,7 @@ def get():
         'rc_config_header': _('RoundCube configured for FreedomBox email'),
     }
 
-    output = actions.superuser_run('email_server', ['-i', 'rcube', 'check'])
+    output = actions.superuser_run('email_server', ['rcube', 'check'])
     results = json.loads(output)
     for i in range(0, len(results)):
         results[i] = models.Diagnosis.from_json(results[i], translation.get)
@@ -41,14 +41,14 @@ def get():
 
 
 def repair():
-    actions.superuser_run('email_server', ['-i', 'rcube', 'set_up'])
+    actions.superuser_run('email_server', ['rcube', 'set_up'])
 
 
 def repair_component(action):
     action_to_services = {'set_up': []}
     if action not in action_to_services:
         return
-    actions.superuser_run('email_server', ['-i', 'rcube', action])
+    actions.superuser_run('email_server', ['rcube', action])
     return action_to_services[action]
 
 

plinth/modules/email_server/audit/spam.py

@@ -94,7 +94,7 @@ def get():
 
 
 def repair():
-    actions.superuser_run('email_server', ['-i', 'spam', 'set_filter'])
+    actions.superuser_run('email_server', ['spam', 'set_filter'])
 
 
 def check_filter(title=''):

plinth/modules/email_server/audit/tls.py

@@ -90,20 +90,20 @@ def _get_superuser_results(results):
     translation = {
         'cert_availability': _('Has a TLS certificate'),
     }
-    dump = actions.superuser_run('email_server', ['-i', 'tls', 'check'])
+    dump = actions.superuser_run('email_server', ['tls', 'check'])
     for jmap in json.loads(dump):
         results.append(models.Diagnosis.from_json(jmap, translation.get))
 
 
 def repair():
-    actions.superuser_run('email_server', ['-i', 'tls', 'set_up'])
+    actions.superuser_run('email_server', ['tls', 'set_up'])
 
 
 def repair_component(action):
     action_to_services = {'set_cert': ['dovecot', 'postfix']}
     if action not in action_to_services:  # action not allowed
         return
-    actions.superuser_run('email_server', ['-i', 'tls', action])
+    actions.superuser_run('email_server', ['tls', action])
     return action_to_services[action]