qubesadmin: define methods list_vmclass and list_devicesclass

Adapt also previous direct calls of qubesdb

QubesOS/qubes-issues#5213

qubesadmin/app.py

@@ -165,6 +165,18 @@ class QubesBase(qubesadmin.base.PropertyHolder):
         self._pool_drivers = None
         self.log = logging.getLogger('app')
 
+    def list_vmclass(self):
+        """Call Qubesd in order to obtain the vm classes list"""
+        vmclass = self.qubesd_call('dom0', 'admin.vmclass.List')\
+            .decode().splitlines()
+        return sorted(vmclass)
+
+    def list_deviceclass(self):
+        """Call Qubesd in order to obtain the device classes list"""
+        deviceclasses = self.qubesd_call('dom0', 'admin.deviceclass.List')\
+            .decode().splitlines()
+        return sorted(deviceclasses)
+
     def _refresh_pool_drivers(self):
         """
         Refresh cached storage pool drivers and their parameters.

qubesadmin/devices.py

@@ -303,17 +303,7 @@ class DeviceManager(dict):
         return self[key]
 
     def __iter__(self):
-        return iter(self._get_device_classes())
+        return iter(self._vm.app.list_deviceclass())
 
     def keys(self):
-        return self._get_device_classes()
-
-    def _get_device_classes(self):
-        """Function used to call Qubesd in order to obtain
-        the device classes list
-        """
-        device_classes = \
-            self._vm.app.qubesd_call('dom0', 'admin.deviceclass.List').decode()
-        device_classes = sorted(device_classes.splitlines())
-
-        return device_classes
+        return self._vm.app.list_deviceclass()

qubesadmin/tools/qvm_create.py

@@ -103,9 +103,8 @@ def main(args=None, app=None):
     args = parser.parse_args(args, app=app)
 
     if args.help_classes:
-        vm_classes = args.app.qubesd_call('dom0', 'admin.vmclass.List').decode()
-        vm_classes = vm_classes.splitlines()
-        print('\n'.join(sorted(vm_classes)))
+        vm_classes = args.app.list_vmclass()
+        print('\n'.join(vm_classes))
         return 0
 
     pools = {}