q-dev: add short way to create DeviceAssignment

qubesadmin/backup/restore.py

@@ -2093,12 +2093,11 @@ def _restore_vms_metadata(self, restore_info):
                         del options['required']
                     else:
                         required = False
-                    assignment = DeviceAssignment(
-                        VirtualDevice(Port(
-                            backend_domain=self.app.domains[backend_domain],
-                            port_id=port_id,
-                            devclass=bus,
-                        )),
+                    assignment = DeviceAssignment.new(
+                        backend_domain=self.app.domains[backend_domain],
+                        port_id=port_id,
+                        devclass=bus,
+                        device_id=None,
                         options=options,
                         mode='required' if required else 'auto-attach',
                     )

qubesadmin/device_protocol.py

@@ -1141,6 +1141,26 @@ def __init__(
             self.mode = AssignmentMode(mode)
         self.frontend_domain = frontend_domain
 
+    @classmethod
+    def new(
+            cls,
+            backend_domain: QubesVM,
+            port_id: str,
+            devclass: str,
+            device_id: Optional[str] = None,
+            frontend_domain: Optional[QubesVM] = None,
+            options=None,
+            mode: Union[str, AssignmentMode] = "manual",
+    ) -> 'DeviceAssignment':
+        return cls(
+            VirtualDevice(
+                Port(backend_domain, port_id, devclass),
+                device_id),
+            frontend_domain,
+            options,
+            mode
+        )
+
     def clone(self, **kwargs):
         """
         Clone object and substitute attributes with explicitly given.

qubesadmin/tests/devices.py

@@ -119,9 +119,8 @@ def test_020_attach(self):
              b"backend_domain='test-vm2' mode='manual' "
              b"frontend_domain='test-vm'")] = \
             b'0\0'
-        assign = DeviceAssignment(
-            VirtualDevice(Port(
-                self.app.domains['test-vm2'], 'dev1', devclass='test',)))
+        assign = DeviceAssignment.new(
+            self.app.domains['test-vm2'], 'dev1', devclass='test')
         self.vm.devices['test'].attach(assign)
         self.assertAllCalled()
 
@@ -132,9 +131,8 @@ def test_021_attach_options(self):
              b"backend_domain='test-vm2' mode='manual' "
              b"frontend_domain='test-vm' _ro='True' "
              b"_something='value'")] = b'0\0'
-        assign = DeviceAssignment(
-            VirtualDevice(Port(
-                self.app.domains['test-vm2'], 'dev1', devclass='test')))
+        assign = DeviceAssignment.new(
+            self.app.domains['test-vm2'], 'dev1', devclass='test')
         assign.options['ro'] = True
         assign.options['something'] = 'value'
         self.vm.devices['test'].attach(assign)
@@ -146,9 +144,8 @@ def test_022_attach_required(self):
              b"device_id='*' port_id='dev1' devclass='test' "
              b"backend_domain='test-vm2' mode='required' "
              b"frontend_domain='test-vm'")] = b'0\0'
-        assign = DeviceAssignment(
-            VirtualDevice(Port(
-                self.app.domains['test-vm2'], 'dev1', devclass='test')),
+        assign = DeviceAssignment.new(
+            self.app.domains['test-vm2'], 'dev1', devclass='test',
             mode='required')
         self.vm.devices['test'].attach(assign)
         self.assertAllCalled()
@@ -159,9 +156,8 @@ def test_023_attach_required_options(self):
              b"device_id='*' port_id='dev1' devclass='test' "
              b"backend_domain='test-vm2' mode='required' "
              b"frontend_domain='test-vm' _ro='True'")] = b'0\0'
-        assign = DeviceAssignment(
-            VirtualDevice(Port(
-                self.app.domains['test-vm2'], 'dev1', devclass='test')),
+        assign = DeviceAssignment.new(
+            self.app.domains['test-vm2'], 'dev1', devclass='test',
             mode='required')
         assign.options['ro'] = True
         self.vm.devices['test'].attach(assign)
@@ -171,9 +167,8 @@ def test_030_detach(self):
         self.app.expected_calls[
             ('test-vm', 'admin.vm.device.test.Detach', 'test-vm2+dev1:*',
              None)] = b'0\0'
-        assign = DeviceAssignment(
-            VirtualDevice(Port(
-                self.app.domains['test-vm2'], 'dev1', devclass='test')))
+        assign = DeviceAssignment.new(
+            self.app.domains['test-vm2'], 'dev1', devclass='test')
         self.vm.devices['test'].detach(assign)
         self.assertAllCalled()
 
@@ -293,42 +288,26 @@ def test_070_update_assignment_required(self):
         self.app.expected_calls[
             ('test-vm', 'admin.vm.device.test.Set.assignment',
              'test-vm2+dev1:*', b'required')] = b'0\0'
-        dev = DeviceAssignment(
-            VirtualDevice(
-                Port(
-                    self.app.domains['test-vm2'],
-                    devclass='test',
-                    port_id='dev1'),
-            ))
+        dev = DeviceAssignment.new(
+            self.app.domains['test-vm2'], devclass='test', port_id='dev1')
         self.vm.devices['test'].update_assignment(dev, AssignmentMode.REQUIRED)
         self.assertAllCalled()
 
     def test_071_update_assignment_ask(self):
         self.app.expected_calls[
             ('test-vm', 'admin.vm.device.test.Set.assignment',
              'test-vm2+dev1:*', b'ask-to-attach')] = b'0\0'
-        dev = DeviceAssignment(
-            VirtualDevice(
-                Port(
-                    self.app.domains['test-vm2'],
-                    devclass='test',
-                    port_id='dev1'),
-            ))
+        dev = DeviceAssignment.new(
+            self.app.domains['test-vm2'], devclass='test', port_id='dev1')
         self.vm.devices['test'].update_assignment(dev, AssignmentMode.ASK)
         self.assertAllCalled()
 
     def test_072_update_assignment_auto(self):
         self.app.expected_calls[
             ('test-vm', 'admin.vm.device.test.Set.assignment',
              'test-vm2+dev1:*', b'auto-attach')] = b'0\0'
-        dev = DeviceAssignment(
-            VirtualDevice(
-                Port(
-                    self.app.domains['test-vm2'],
-                    devclass='test',
-                    port_id='dev1',
-                )
-            ))
+        dev = DeviceAssignment.new(
+            self.app.domains['test-vm2'], devclass='test', port_id='dev1')
         self.vm.devices['test'].update_assignment(dev, AssignmentMode.AUTO)
         self.assertAllCalled()
 

qubesadmin/tools/qvm_start.py

@@ -159,13 +159,9 @@ def get_drive_assignment(app, drive_str):
         'devtype': devtype,
         'read-only': devtype == 'cdrom'
     }
-    assignment = DeviceAssignment(VirtualDevice(Port(
-            backend_domain=backend_domain,
-            port_id=port_id,
-            devclass='block',
-        )),
-        options=options,
-        mode="required")
+    assignment = DeviceAssignment.new(
+        backend_domain=backend_domain, port_id=port_id, devclass='block',
+        options=options, mode="required")
 
     return assignment