Improve qvm-backup-restore --paranoid-mode

doc/manpages/qvm-backup-restore.rst

@@ -101,6 +101,8 @@ Options
     - dom0 home directory (desktop environment settings)
     - PCI devices assignments
 
+  This operation requires `qubes-core-admin-client` package in the DisposableVM
+
 .. option:: --auto-close
 
   When running with --paranoid-mode (see above), automatically close restore

qubesadmin/backup/dispvm.py

@@ -276,10 +276,27 @@ def run(self):
         lock = qubesadmin.utils.LockFile(LOCKFILE, True)
         lock.acquire()
         try:
+            self.app.log.info("Starting restore process in a DisposableVM...")
             self.create_dispvm()
             self.clear_old_tags()
             self.register_backup_source()
             self.dispvm.start()
+            try:
+                self.app.log.debug(
+                    "Checking for existence of qubes-core-admin-client"
+                )
+                self.dispvm.run("command -v qvm-backup-restore")
+            except subprocess.CalledProcessError:
+                raise qubesadmin.exc.QubesException(
+                    'qvm-backup-restore tool '
+                    'missing in {} template, install qubes-core-admin-client '
+                    'package there'.format(
+                        getattr(self.dispvm.template,
+                                'template',
+                                self.dispvm.template).name)
+                )
+            self.app.log.info("When operation completes, close its window "
+                              "manually.")
             self.dispvm.run_service_for_stdio('qubes.WaitForSession')
             if self.args.pass_file:
                 self.args.pass_file = self.transfer_pass_file(

qubesadmin/tests/backup/dispvm.py

@@ -330,6 +330,7 @@ def test_100_run(self):
             self.assertEqual(len(getattr(obj, m).mock_calls), 1)
         self.assertEqual(obj.dispvm.mock_calls, [
             call.start(),
+            call.run('command -v qvm-backup-restore'),
             call.run_service_for_stdio('qubes.WaitForSession'),
             call.tags.add('backup-restore-mgmt'),
             call.run_with_args('terminal', 'qvm-backup-restore', 'args',
@@ -368,6 +369,7 @@ def test_101_run_pass_file(self):
             self.assertEqual(len(getattr(obj, m).mock_calls), 1)
         self.assertEqual(obj.dispvm.mock_calls, [
             call.start(),
+            call.run('command -v qvm-backup-restore'),
             call.run_service_for_stdio('qubes.WaitForSession'),
             call.tags.add('backup-restore-mgmt'),
             call.run_with_args('terminal', 'qvm-backup-restore', 'args',
@@ -405,6 +407,7 @@ def test_102_run_error(self):
             self.assertEqual(len(getattr(obj, m).mock_calls), 1)
         self.assertEqual(obj.dispvm.mock_calls, [
             call.start(),
+            call.run('command -v qvm-backup-restore'),
             call.run_service_for_stdio('qubes.WaitForSession'),
             call.tags.add('backup-restore-mgmt'),
             call.run_with_args('terminal', 'qvm-backup-restore', 'args',
@@ -414,3 +417,39 @@ def test_102_run_error(self):
             call.kill()
         ])
         obj.transfer_pass_file.assert_not_called()
+
+    def test_103_missing_package(self):
+        self.app.expected_calls[('dom0', 'admin.vm.List', None, None)] = (
+            b'0\0dom0 class=AdminVM state=Running\n'
+            b'fedora-25 class=TemplateVM state=Halted\n'
+        )
+        args = unittest.mock.Mock(backup_location='/backup/path',
+            pass_file=None,
+            appvm=None)
+        obj = RestoreInDisposableVM(self.app, args)
+        methods = ['create_dispvm', 'clear_old_tags', 'register_backup_source',
+                   'finalize_tags']
+        for m in methods:
+            setattr(obj, m, unittest.mock.Mock())
+        obj.transfer_pass_file = unittest.mock.Mock()
+        obj.dispvm = unittest.mock.Mock()
+        obj.dispvm.run = unittest.mock.Mock()
+        obj.dispvm.run.side_effect = subprocess.CalledProcessError(
+            '1',
+            'command -v qvm-backup-restore',
+        )
+        with tempfile.NamedTemporaryFile() as tmp:
+            with unittest.mock.patch('qubesadmin.backup.dispvm.LOCKFILE',
+                    tmp.name):
+                with self.assertRaises(qubesadmin.exc.QubesException):
+                    obj.run()
+        # pylint: disable=no-member
+        for m in methods:
+            self.assertEqual(len(getattr(obj, m).mock_calls), 1)
+        self.assertEqual(obj.dispvm.mock_calls, [
+            call.start(),
+            call.run('command -v qvm-backup-restore'),
+            call.tags.discard('backup-restore-mgmt'),
+            call.kill()
+        ])
+        obj.transfer_pass_file.assert_not_called()

qubesadmin/tools/qvm_backup_restore.py

@@ -240,9 +240,6 @@ def main(args=None, app=None):
 
     if args.paranoid_mode:
         args.dom0_home = False
-        args.app.log.info("Starting restore process in a DisposableVM...")
-        args.app.log.info("When operation completes, close its window "
-                          "manually.")
         restore_in_dispvm = RestoreInDisposableVM(args.app, args)
         try:
             backup_log = restore_in_dispvm.run()