command line shortcut for the permission setup

README.md

@@ -61,12 +61,11 @@ you can read information from your devices. You have to start the application
 via sudo otherwise. You may also need to grant yourself write access to
 `/dev/uinput` to be able to inject your programmed mapping.
 
+There is a shortcut for configuring this stuff:
+
 ```bash
-# either use sudo key-mapper-gtk or
-sudo usermod -a -G plugdev,input $USER
-sudo setfacl -m u:$USER:rw- /dev/uinput
-# log out and back in or restart, the two groups should be visible with:
-groups
+sudo key-mapper-service --setup-permissions
+# now log out and back in
 ```
 
 ##### Manjaro/Arch

bin/key-mapper-service

@@ -23,7 +23,9 @@
 
 
 import sys
+import os
 import atexit
+import grp
 from argparse import ArgumentParser
 
 import gi
@@ -35,9 +37,27 @@ from keymapper.logger import update_verbosity, log_info, \
     add_filehandler, logger
 from keymapper.daemon import Daemon, BUS_NAME
 from keymapper.state import system_mapping
+from keymapper.paths import USER
 from keymapper.dev.permissions import can_read_devices
 
 
+def run(cmd):
+    """Run and log a command."""
+    logger.info('Running `%s`...', cmd)
+    code = os.system(cmd)
+    if code != 0:
+        logger.error('Failed. exit code %d', code)
+
+
+def group_exists(name):
+    """Check if a group with that name exists."""
+    try:
+        grp.getgrnam(name)
+        return True
+    except KeyError:
+        return False
+
+
 if __name__ == '__main__':
     parser = ArgumentParser()
     parser.add_argument(
@@ -50,6 +70,14 @@ if __name__ == '__main__':
         help='Print all available names for the mapping',
         default=False
     )
+    parser.add_argument(
+        '-s', '--setup-permissions', action='store_true', dest='setup',
+        help=(
+            'Requires sudo. Sets up all needed permissions to run'
+            'key-mapper as regular user'
+        ),
+        default=False
+    )
 
     options = parser.parse_args(sys.argv[1:])
 
@@ -62,6 +90,26 @@ if __name__ == '__main__':
         print('\n'.join(system_mapping.list_names()))
         sys.exit(0)
 
+    if options.setup:
+        if os.environ['USER'] != 'root' or USER == 'root':
+            # USER should contain the actual non-root user
+            logger.error('This only works using sudo')
+            sys.exit(1)
+
+        if group_exists('input'):
+            run('usermod -a -G input $USER')
+
+        if group_exists('plugdev'):
+            run('usermod -a -G plugdev $USER')
+
+        run('setfacl -m u:$USER:rw- /dev/uinput')
+
+        logger.info(
+            'For these changes to take effect log out and in. '
+            'In some environments you may need to reboot.'
+        )
+        sys.exit(0)
+
     can_read_devices()
 
     bus = SessionBus()

keymapper/dev/permissions.py

@@ -51,7 +51,7 @@ def check_group(group):
         msg = (
             'Some devices may not be visible without being in the '
             f'"{group}" user group. Try `sudo usermod -a -G {group} {USER}` '
-            'and log out and back in or restart.',
+            'and log out and back in or restart.'
         )
         logger.warning(msg)
         return msg
@@ -67,9 +67,8 @@ def check_group(group):
     if in_group and not group_active:
         msg = (
             f'You are in the "{group}" group, but your session is not yet '
-            'using it. Some device may not be visible. Please log out and '
-            'back in or restart',
-            group
+            'using it. Some devices may not be visible. Please log out and '
+            'back in or restart'
         )
         logger.warning(msg)
         return msg
@@ -80,12 +79,12 @@ def check_group(group):
 def check_injection_rights():
     """Check if the user may write into /dev/uinput."""
     if not os.access('/dev/uinput', os.W_OK):
-        can_write = (
+        msg = (
             'Rights to write to /dev/uinput are missing, keycodes cannot '
             f'be injected. Try `sudo setfacl -m u:{USER}:rw- /dev/uinput`'
         )
-        logger.error(can_write)
-        return can_write
+        logger.error(msg)
+        return msg
 
     return None
 
@@ -109,4 +108,10 @@ def can_read_devices():
     if plugdev_check is not None:
         ret.append(plugdev_check)
 
+    if len(ret) > 0:
+        logger.info(
+            'You can also use `sudo key-mapper-service --setup-permissions` '
+            'as a shortcut for mentioned commands.'
+        )
+
     return ret

keymapper/gtk/window.py

@@ -113,9 +113,15 @@ def __init__(self):
         permission_errors = can_read_devices()
         if len(permission_errors) > 0:
             # TODO test
+            permission_errors = [(
+                'You can also try `sudo key-mapper-service --setup-permiss'
+                'ions` to setup all needed permissions for you. All '
+                'commands mentioned here are also printed to the console '
+                'for you to copy.'
+            )] + permission_errors
             self.show_status(
                 CTX_ERROR,
-                'Permission error. Hover for info',
+                'Permission error, hover for info',
                 '\n\n'.join(permission_errors)
             )
 
@@ -288,7 +294,6 @@ def show_status(self, context_id, message, tooltip=None):
 
     def check_macro_syntax(self):
         """Check if the programmed macros are allright."""
-        # test macros for syntax errors
         # TODO test
         for (ev_type, keycode), output in custom_mapping:
             if not is_this_a_macro(output):

keymapper/paths.py

@@ -35,7 +35,11 @@
     # failed in some ubuntu installations
     USER = os.environ['USER']
     if USER == 'root':
-        USER = os.environ.get('SUDO_USER', USER)
+        try:
+            USER = os.environ.get('SUDO_USER', USER)
+        except KeyError:
+            # no sudo was used
+            pass
 
 CONFIG = os.path.join('/home', USER, '.config/key-mapper')