some improved verbosity on groups and missing devices

keymapper/dev/injector.py

@@ -133,6 +133,10 @@ class KeycodeInjector:
             # started once.
             raise Exception('Please construct a new injector instead')
 
+        if self.device not in get_devices():
+            logger.error('Cannot inject for unknown device "%s"', self.device)
+            return
+
         self._process = multiprocessing.Process(target=self._start_injecting)
         self._process.start()
 
@@ -279,7 +283,7 @@ class KeycodeInjector:
         loop = asyncio.get_event_loop()
         coroutines = []
 
-        logger.info('Starting injecting the mapping for %s', self.device)
+        logger.info('Starting injecting the mapping for "%s"', self.device)
 
         paths = get_devices()[self.device]['paths']
 

keymapper/dev/permissions.py

@@ -50,4 +50,6 @@ def can_read_devices():
         if not is_in_input_group:
             warn('input')
 
-    return is_root or (is_in_input_group and is_in_plugdev_group)
+    ok = is_root or (is_in_input_group and is_in_plugdev_group)
+
+    return ok, is_root, is_in_input_group, is_in_plugdev_group

keymapper/gtk/window.py

@@ -42,6 +42,7 @@ from keymapper.gtk.unsaved import unsaved_changes_dialog, GO_BACK
 from keymapper.dev.reader import keycode_reader
 from keymapper.daemon import get_dbus_interface
 from keymapper.config import config
+from keymapper.dev.permissions import can_read_devices
 
 
 def gtk_iteration():
@@ -110,9 +111,24 @@ class Window:
         self.window = window
 
         # if any of the next steps take a bit to complete, have the window
-        # already visible to make it look more responsive.
+        # already visible (without content) to make it look more responsive.
         gtk_iteration()
 
+        ok, _, is_input, is_plugdev = can_read_devices()
+        if not ok:
+            missing_groups = []
+            if not is_input:
+                missing_groups.append('input')
+            if not is_plugdev:
+                missing_groups.append('plugdev')
+
+            if len(missing_groups) > 0:
+                self.get('status_bar').push(
+                    CTX_ERROR,
+                    f'You are not in the {" and ".join(missing_groups)} '
+                    f'group{"s" if len(missing_groups) > 0 else ""}'
+                )
+
         self.populate_devices()
 
         self.select_newest_preset()

tests/testcases/test_permissions.py

@@ -19,7 +19,6 @@
 # along with key-mapper.  If not, see <https://www.gnu.org/licenses/>.
 
 
-import os
 import grp
 import unittest
 
@@ -40,7 +39,7 @@ class TestPermissions(unittest.TestCase):
                 self.gr_mem = []
 
         grp.getgrnam = Grnam
-        self.assertFalse(can_read_devices())
+        self.assertFalse(can_read_devices()[0])
 
     def test_can_access(self):
         class Grnam:
@@ -48,7 +47,7 @@ class TestPermissions(unittest.TestCase):
                 self.gr_mem = [USER]
 
         grp.getgrnam = Grnam
-        self.assertTrue(can_read_devices())
+        self.assertTrue(can_read_devices()[0])
 
 
 if __name__ == "__main__":