tools/qvm-pool: add --set to modify pool properties

Fixes QubesOS/qubes-issues#3256

doc/manpages/qvm-pool.rst

@@ -51,6 +51,11 @@ Options
     qubes.xml, but does not delete any content (FIXME: is it really true for
     all pool drivers?).
 
+.. option:: --set NAME, -s NAME
+
+    Modify a pool. This set options of a pool. Use ``--o`` to specify actual modifications.
+
+
 Examples
 --------
 

qubesadmin/tests/tools/qvm_pool.py

@@ -92,3 +92,25 @@ class TC_00_qvm_pool(qubesadmin.tests.QubesTestCase):
             'volume_group  qubes_dom0\n'
             )
         self.assertAllCalled()
+
+    def test_050_set(self):
+        self.app.expected_calls[('dom0', 'admin.pool.List', None, None)] = \
+            b'0\x00pool-file\npool-lvm\n'
+        self.app.expected_calls[
+            ('dom0', 'admin.pool.Set.revisions_to_keep', 'pool-lvm', b'2')] = \
+            b'0\x00'
+        self.assertEqual(0,
+            qubesadmin.tools.qvm_pool.main(['-s', 'pool-lvm', '-o',
+                'revisions_to_keep=2'],
+                app=self.app))
+        self.assertAllCalled()
+
+    def test_051_set_invalid(self):
+        self.app.expected_calls[('dom0', 'admin.pool.List', None, None)] = \
+            b'0\x00pool-file\npool-lvm\n'
+        with self.assertRaises(SystemExit) as e:
+            qubesadmin.tools.qvm_pool.main(
+                ['-s', 'pool-lvm', '-o', 'prop=1'],
+                app=self.app)
+        self.assertEqual(e.exception.code, 2)
+        self.assertAllCalled()

qubesadmin/tools/qvm_pool.py

@@ -92,6 +92,23 @@ class _Add(argparse.Action):
         setattr(namespace, 'driver', driver)
 
 
+class _Set(qubesadmin.tools.PoolsAction):
+    ''' Action for argument parser that sets pool options. '''
+
+    def __init__(self, option_strings, dest=None, default=None, metavar=None):
+        super(_Set, self).__init__(option_strings=option_strings,
+                                   dest=dest,
+                                   metavar=metavar,
+                                   default=default,
+                                   help='modify pool (use -o to specify '
+                                        'modifications)')
+
+    def __call__(self, parser, namespace, name, option_string=None):
+        print('dupa')
+        setattr(namespace, 'command', 'set')
+        super(_Set, self).__call__(parser, namespace, name, option_string)
+
+
 class _Options(argparse.Action):
     ''' Action for argument parser that parsers options. '''
 
@@ -127,6 +144,8 @@ def get_parser():
                        dest='command',
                        metavar=('NAME', 'DRIVER'))
     group.add_argument('-r', '--remove', metavar='NAME', action=_Remove)
+    group.add_argument('-s', '--set', metavar='POOLNAME', dest='pool',
+                       action=_Set, default=[])
     group.add_argument('--help-drivers',
                        dest='command',
                        const='list-drivers',
@@ -173,6 +192,17 @@ def main(args=None, app=None):
     elif args.command == 'info':
         for pool in args.pools:
             pool_info(pool)
+    elif args.command == 'set':
+        pool = args.pool[0]
+        for opt, value in args.options.items():
+            if not hasattr(type(pool), opt):
+                parser.error('setting pool option %s is not supported' % (
+                    pool.name))
+            try:
+                setattr(pool, opt, value)
+            except qubesadmin.exc.QubesException as e:
+                parser.error('failed to set pool %s option %s: %s\n' % (
+                    pool.name, opt, str(e)))
     return 0