Add restrictions on updated_at when getting migrations

If ``changes-before`` is less than ``changes-since`` in requested,
there will get empty data when querying in db, so add the limit of
these parameters. If ``changes-before`` < ``changes-since``, will
be returned 400.

Closes-Bug: #1796008
Change-Id: I2a39ac5a9fe969d383099b4e766c46ad05d9f67c

api-ref/source/parameters.yaml

@@ -485,6 +485,9 @@ changes_before_migration:
     The ``±hh:mm`` value, if included, returns the time zone as an offset from UTC.
     For example, ``2015-08-27T09:49:58-05:00``.
     If you omit the time zone, the UTC time zone is assumed.
+    When both ``changes-since`` and ``changes-before`` are specified,
+    the value of the ``changes-before`` must be later than or equal to
+    the value of the ``changes-since`` otherwise API will return 400.
   in: query
   required: false
   type: string
@@ -538,6 +541,9 @@ changes_since_migration:
     The ``±hh:mm`` value, if included, returns the time zone as an offset from UTC.
     For example, ``2015-08-27T09:49:58-05:00``.
     If you omit the time zone, the UTC time zone is assumed.
+    When both ``changes-since`` and ``changes-before`` are specified,
+    the value of the ``changes-since`` must be earlier than or equal to
+    the value of the ``changes-before`` otherwise API will return 400.
   in: query
   required: false
   type: string

nova/api/openstack/compute/migrations.py

@@ -20,6 +20,7 @@ from nova.api.openstack import wsgi
 from nova.api import validation
 from nova import compute
 from nova import exception
+from nova.i18n import _
 from nova.objects import base as obj_base
 from nova.policies import migrations as migrations_policies
 
@@ -96,6 +97,12 @@ class MigrationsController(wsgi.Controller):
             if allow_changes_before:
                 search_opts['changes-before'] = timeutils.parse_isotime(
                     search_opts['changes-before'])
+                changes_since = search_opts.get('changes-since')
+                if (changes_since and search_opts['changes-before'] <
+                        search_opts['changes-since']):
+                    msg = _('The value of changes-since must be less than '
+                            'or equal to changes-before.')
+                    raise exc.HTTPBadRequest(explanation=msg)
             else:
                 # Before microversion 2.59 the schema allowed
                 # additionalProperties=True, so a user could pass

nova/tests/unit/api/openstack/compute/test_migrations.py

@@ -14,6 +14,7 @@
 
 import datetime
 
+import iso8601
 import mock
 from oslo_utils.fixture import uuidsentinel as uuids
 import six
@@ -363,6 +364,44 @@ class MigrationTestCaseV266(MigrationsTestCaseV259):
         self.assertRaises(exception.ValidationError,
                           self.controller.index, req)
 
+    @mock.patch('nova.compute.api.API.get_migrations_sorted',
+                return_value=objects.MigrationList())
+    def test_index_with_changes_since_and_changes_before(
+            self, get_migrations_sorted):
+        changes_since = '2013-10-22T13:42:02Z'
+        changes_before = '2013-10-22T13:42:03Z'
+        req = fakes.HTTPRequest.blank(
+            '/os-migrations?changes-since=%s&changes-before=%s&'
+            'instance_uuid=%s'
+            % (changes_since, changes_before, uuids.instance_uuid),
+            version=self.wsgi_api_version,
+            use_admin_context=True)
+
+        self.controller.index(req)
+        search_opts = {'instance_uuid': uuids.instance_uuid,
+                       'changes-before':
+                           datetime.datetime(2013, 10, 22, 13, 42, 3,
+                                             tzinfo=iso8601.iso8601.UTC),
+                       'changes-since':
+                           datetime.datetime(2013, 10, 22, 13, 42, 2,
+                                             tzinfo=iso8601.iso8601.UTC)}
+        get_migrations_sorted.assert_called_once_with(
+            req.environ['nova.context'], search_opts, sort_dirs=mock.ANY,
+            sort_keys=mock.ANY, limit=1000, marker=None)
+
+    def test_get_migrations_filters_with_distinct_changes_time_bad_request(
+            self):
+        changes_since = '2018-09-04T05:45:27Z'
+        changes_before = '2018-09-03T05:45:27Z'
+        req = fakes.HTTPRequest.blank('/os-migrations?'
+                                      'changes-since=%s&changes-before=%s' %
+                                      (changes_since, changes_before),
+                                      version=self.wsgi_api_version,
+                                      use_admin_context=True)
+        ex = self.assertRaises(exc.HTTPBadRequest, self.controller.index, req)
+        self.assertIn('The value of changes-since must be less than '
+                      'or equal to changes-before', six.text_type(ex))
+
     def test_index_with_changes_before_old_microversion_failed(self):
         """Tests that the changes-before query parameter is an error before
         microversion 2.66.