diff --git a/nova/api/validation/parameter_types.py b/nova/api/validation/parameter_types.py
index 5ca9a19daf..72ae212099 100644
--- a/nova/api/validation/parameter_types.py
+++ b/nova/api/validation/parameter_types.py
@@ -15,6 +15,7 @@
 Common parameter types for validating request Body.
 
 """
+
 import copy
 import functools
 import re
@@ -27,7 +28,6 @@ _REGEX_RANGE_CACHE = {}
 
 
 def memorize(func):
-
     @functools.wraps(func)
     def memorizer(*args, **kwargs):
         global _REGEX_RANGE_CACHE
@@ -37,6 +37,7 @@ def memorize(func):
             value = func(*args, **kwargs)
             _REGEX_RANGE_CACHE[key] = value
         return value
+
     return memorizer
 
 
@@ -103,6 +104,7 @@ def _get_all_chars():
 # constraint fails and this causes issues for some unittests when
 # PYTHONHASHSEED is set randomly.
 
+
 @memorize
 def _build_regex_range(ws=True, invert=False, exclude=None):
     """Build a range regex for a set of characters in utf8.
@@ -139,8 +141,7 @@ def _build_regex_range(ws=True, invert=False, exclude=None):
         else:
             # Zs is the unicode class for space characters, of which
             # there are about 10 in this range.
-            result = (_is_printable(char) and
-                      unicodedata.category(char) != "Zs")
+            result = _is_printable(char) and unicodedata.category(char) != 'Zs'
         if invert is True:
             return not result
         return result
@@ -165,7 +166,6 @@ def _build_regex_range(ws=True, invert=False, exclude=None):
 
 valid_name_regex_base = '^(?![%s])[%s]*(?<![%s])$'
 
-
 valid_name_regex = ValidationRegex(
     valid_name_regex_base % (
         _build_regex_range(ws=False, invert=True),
@@ -173,13 +173,11 @@ valid_name_regex = ValidationRegex(
         _build_regex_range(ws=False, invert=True)),
     _("printable characters. Can not start or end with whitespace."))
 
-
 # This regex allows leading/trailing whitespace
 valid_name_leading_trailing_spaces_regex_base = (
     "^[%(ws)s]*[%(no_ws)s]+[%(ws)s]*$|"
     "^[%(ws)s]*[%(no_ws)s][%(no_ws)s%(ws)s]+[%(no_ws)s][%(ws)s]*$")
 
-
 valid_az_name_regex = ValidationRegex(
     valid_name_regex_base % (
         _build_regex_range(ws=False, invert=True),
@@ -188,7 +186,6 @@ valid_az_name_regex = ValidationRegex(
     _("printable characters except :."
       "Can not start or end with whitespace."))
 
-
 # az's name disallow ':'.
 valid_az_name_leading_trailing_spaces_regex = ValidationRegex(
     valid_name_leading_trailing_spaces_regex_base % {
@@ -197,20 +194,15 @@ valid_az_name_leading_trailing_spaces_regex = ValidationRegex(
     _("printable characters except :, "
       "with at least one non space character"))
 
-
 valid_name_leading_trailing_spaces_regex = ValidationRegex(
     valid_name_leading_trailing_spaces_regex_base % {
         'ws': _build_regex_range(),
         'no_ws': _build_regex_range(ws=False)},
     _("printable characters with at least one non space character"))
 
-
 valid_description_regex_base = '^[%s]*$'
 
-
-valid_description_regex = valid_description_regex_base % (
-    _build_regex_range())
-
+valid_description_regex = valid_description_regex_base % (_build_regex_range())
 
 boolean = {
     'type': ['boolean', 'string'],
@@ -221,11 +213,6 @@ boolean = {
 }
 
 
-none = {
-    'enum': ['None', None, {}]
-}
-
-
 name_or_none = {
     'oneOf': [
         {'type': 'string', 'minLength': 1, 'maxLength': 255},
@@ -233,16 +220,18 @@ name_or_none = {
     ]
 }
 
-
 positive_integer = {
     'type': ['integer', 'string'],
-    'pattern': '^[0-9]*$', 'minimum': 1, 'minLength': 1
+    'pattern': '^[0-9]*$',
+    'minimum': 1,
+    'minLength': 1,
 }
 
-
 non_negative_integer = {
     'type': ['integer', 'string'],
-    'pattern': '^[0-9]*$', 'minimum': 0, 'minLength': 1
+    'pattern': '^[0-9]*$',
+    'minimum': 0,
+    'minLength': 1,
 }
 
 # A host-specific or leaf label.
@@ -272,79 +261,100 @@ non_negative_integer = {
 #   handle host names of up to 255 characters.
 hostname = {
     'type': 'string',
+    'pattern': '^[a-zA-Z0-9]+[a-zA-Z0-9-]*[a-zA-Z0-9]+$',
     'minLength': 2,
     'maxLength': 63,
-    'pattern': '^[a-zA-Z0-9]+[a-zA-Z0-9-]*[a-zA-Z0-9]+$',
 }
 
 fqdn = {
-    'type': 'string', 'minLength': 1, 'maxLength': 255,
+    'type': 'string',
     # NOTE: 'host' is defined in "services" table, and that
     # means a hostname. The hostname grammar in RFC952 does
     # not allow for underscores in hostnames. However, this
     # schema allows them, because it sometimes occurs in
     # real systems.
     'pattern': '^[a-zA-Z0-9-._]*$',
+    'minLength': 1,
+    'maxLength': 255,
 }
 
-
 name = {
     # NOTE: Nova v2.1 API contains some 'name' parameters such
     # as server, flavor, aggregate and so on. They are
     # stored in the DB and Nova specific parameters.
     # This definition is used for all their parameters.
-    'type': 'string', 'minLength': 1, 'maxLength': 255,
-    'format': 'name'
+    'type': 'string',
+    'format': 'name',
+    'minLength': 1,
+    'maxLength': 255,
 }
 
-
 az_name = {
-    'type': 'string', 'minLength': 1, 'maxLength': 255,
-    'format': 'az_name'
+    'type': 'string',
+    'format': 'az_name',
+    'minLength': 1,
+    'maxLength': 255,
 }
 
+keypair_name_special_chars = {
+    'allOf': [
+        name,
+        {
+            'type': 'string',
+            'pattern': r'^[_\- a-zA-Z0-9]+$',
+            'minLength': 1,
+            'maxLength': 255,
+        },
+    ]
+}
 
-keypair_name_special_chars = {'allOf': [name, {
-    'type': 'string', 'minLength': 1, 'maxLength': 255,
-    'format': 'keypair_name_20'
-}]}
-
-
-keypair_name_special_chars_292 = {'allOf': [name, {
-    'type': 'string', 'minLength': 1, 'maxLength': 255,
-    'format': 'keypair_name_292'
-}]}
-
+keypair_name_special_chars_292 = {
+    'allOf': [
+        name,
+        {
+            'type': 'string',
+            'pattern': r'^[_\-\@\. a-zA-Z0-9]+$',
+            'minLength': 1,
+            'maxLength': 255,
+        },
+    ]
+}
 
 az_name_with_leading_trailing_spaces = {
-    'type': 'string', 'minLength': 1, 'maxLength': 255,
-    'format': 'az_name_with_leading_trailing_spaces'
+    'type': 'string',
+    'format': 'az_name_with_leading_trailing_spaces',
+    'minLength': 1,
+    'maxLength': 255,
 }
 
-
 name_with_leading_trailing_spaces = {
-    'type': 'string', 'minLength': 1, 'maxLength': 255,
-    'format': 'name_with_leading_trailing_spaces'
+    'type': 'string',
+    'format': 'name_with_leading_trailing_spaces',
+    'minLength': 1,
+    'maxLength': 255,
 }
 
-
 description = {
-    'type': ['string', 'null'], 'minLength': 0, 'maxLength': 255,
+    'type': ['string', 'null'],
     'pattern': valid_description_regex,
+    'minLength': 0,
+    'maxLength': 255,
 }
 
-
 # TODO(stephenfin): This is no longer used and should be removed
 tcp_udp_port = {
-    'type': ['integer', 'string'], 'pattern': '^[0-9]*$',
-    'minimum': 0, 'maximum': 65535,
-    'minLength': 1
+    'type': ['integer', 'string'],
+    'pattern': '^[0-9]*$',
+    'minimum': 0,
+    'maximum': 65535,
+    'minLength': 1,
 }
 
-
 project_id = {
-    'type': 'string', 'minLength': 1, 'maxLength': 255,
-    'pattern': '^[a-zA-Z0-9-]*$'
+    'type': 'string',
+    'pattern': '^[a-zA-Z0-9-]*$',
+    'minLength': 1,
+    'maxLength': 255,
 }
 
 user_id = {
@@ -355,12 +365,13 @@ user_id = {
 }
 
 server_id = {
-    'type': 'string', 'format': 'uuid'
+    'type': 'string',
+    'format': 'uuid',
 }
 
-
 image_id = {
-    'type': 'string', 'format': 'uuid'
+    'type': 'string',
+    'format': 'uuid',
 }
 
 share_id = {
@@ -384,36 +395,36 @@ share_status = {
 image_id_or_empty_string = {
     'oneOf': [
         {'type': 'string', 'format': 'uuid'},
-        {'type': 'string', 'maxLength': 0}
+        {'type': 'string', 'maxLength': 0},
     ]
 }
 
-
 volume_id = {
-    'type': 'string', 'format': 'uuid'
+    'type': 'string',
+    'format': 'uuid',
 }
 
-
 attachment_id = {
-    'type': 'string', 'format': 'uuid'
+    'type': 'string',
+    'format': 'uuid',
 }
 
-
 volume_type = {
-    'type': ['string', 'null'], 'minLength': 0, 'maxLength': 255
+    'type': ['string', 'null'],
+    'minLength': 0,
+    'maxLength': 255,
 }
 
-
 network_id = {
-    'type': 'string', 'format': 'uuid'
+    'type': 'string',
+    'format': 'uuid',
 }
 
-
 network_port_id = {
-    'type': 'string', 'format': 'uuid'
+    'type': 'string',
+    'format': 'uuid',
 }
 
-
 admin_password = {
     # NOTE: admin_password is the admin password of a server
     # instance, and it is not stored into nova's data base.
@@ -423,12 +434,10 @@ admin_password = {
     'type': 'string',
 }
 
-
 flavor_ref = {
     'type': ['string', 'integer'], 'minLength': 1
 }
 
-
 metadata = {
     'type': 'object',
     'patternProperties': {
@@ -439,18 +448,15 @@ metadata = {
     'additionalProperties': False
 }
 
-
 metadata_with_null = copy.deepcopy(metadata)
 metadata_with_null['patternProperties']['^[a-zA-Z0-9-_:. ]{1,255}$']['type'] =\
     ['string', 'null']
 
-
 mac_address = {
     'type': 'string',
     'pattern': '^([0-9a-fA-F]{2})(:[0-9a-fA-F]{2}){5}$'
 }
 
-
 ip_address = {
     'type': 'string',
     'oneOf': [
@@ -459,22 +465,18 @@ ip_address = {
     ]
 }
 
-
 ipv4 = {
     'type': 'string', 'format': 'ipv4'
 }
 
-
 ipv6 = {
     'type': 'string', 'format': 'ipv6'
 }
 
-
 cidr = {
     'type': 'string', 'format': 'cidr'
 }
 
-
 volume_size = {
     'type': ['integer', 'string'],
     'pattern': '^[0-9]+$',
@@ -501,7 +503,6 @@ accessIPv6 = {
 
 flavor_param_positive = copy.deepcopy(volume_size)
 
-
 flavor_param_non_negative = copy.deepcopy(volume_size)
 flavor_param_non_negative['minimum'] = 0
 
@@ -522,8 +523,9 @@ personality = {
 
 tag = {
     "type": "string",
-    "minLength": 1, "maxLength": tag.MAX_TAG_LENGTH,
-    "pattern": "^[^,/]*$"
+    "pattern": '^[^,/]*$',
+    "minLength": 1,
+    "maxLength": tag.MAX_TAG_LENGTH,
 }
 
 pagination_parameters = {
diff --git a/nova/api/validation/validators.py b/nova/api/validation/validators.py
index ebe7005379..613e16e09f 100644
--- a/nova/api/validation/validators.py
+++ b/nova/api/validation/validators.py
@@ -17,7 +17,6 @@ Internal implementation of request Body validating middleware.
 """
 
 import re
-import string
 
 import jsonschema
 from jsonschema import exceptions as jsonschema_exc
@@ -194,28 +193,6 @@ def _validate_az_name(instance):
     raise exception.InvalidName(reason=regex.reason)
 
 
-@_FORMAT_CHECKER.checks('keypair_name_20',
-                        exception.InvalidName)
-def _validate_keypair_name_20(keypair_name):
-    safe_chars = "_- " + string.digits + string.ascii_letters
-    return _validate_keypair_name(keypair_name, safe_chars)
-
-
-@_FORMAT_CHECKER.checks('keypair_name_292',
-                        exception.InvalidName)
-def _validate_keypair_name_292(keypair_name):
-    safe_chars = "@._- " + string.digits + string.ascii_letters
-    return _validate_keypair_name(keypair_name, safe_chars)
-
-
-def _validate_keypair_name(keypair_name, safe_chars):
-    clean_value = "".join(x for x in keypair_name if x in safe_chars)
-    if clean_value != keypair_name:
-        reason = _("Only expected characters: [%s]") % safe_chars
-        raise exception.InvalidName(reason=reason)
-    return True
-
-
 def _soft_validate_additional_properties(validator,
                                          additional_properties_value,
                                          instance,
diff --git a/nova/tests/unit/api/openstack/compute/test_keypairs.py b/nova/tests/unit/api/openstack/compute/test_keypairs.py
index 79842487c6..f0d941b510 100644
--- a/nova/tests/unit/api/openstack/compute/test_keypairs.py
+++ b/nova/tests/unit/api/openstack/compute/test_keypairs.py
@@ -76,7 +76,6 @@ def db_key_pair_create_duplicate(context):
 
 class KeypairsTestV21(test.TestCase):
     base_url = '/v2/%s' % fakes.FAKE_PROJECT_ID
-    validation_error = exception.ValidationError
     wsgi_api_version = os_wsgi.DEFAULT_API_VERSION
 
     def _setup_app_and_controller(self):
@@ -113,24 +112,12 @@ class KeypairsTestV21(test.TestCase):
         self.assertGreater(len(res_dict['keypair']['private_key']), 0)
         self._assert_keypair_type(res_dict)
 
-    def _test_keypair_create_bad_request_case(
-        self, body, exception, error_msg=None
-    ):
-        if error_msg:
-            self.assertRaisesRegex(exception, error_msg,
-                                   self.controller.create,
-                                   self.req, body=body)
-        else:
-            self.assertRaises(exception,
-                              self.controller.create, self.req, body=body)
-
     def test_keypair_create_with_empty_name(self):
         body = {'keypair': {'name': ''}}
-        self._test_keypair_create_bad_request_case(
-            body,
-            self.validation_error,
-            '(is too short)|'  # jsonschema < 4.23.0
-            '(should be non-empty)')  # jsonschema >= 4.23.0
+        self.assertRaisesRegex(
+            exception.ValidationError,
+            '(is too short)|(should be non-empty)',  # jsonschema < / >= 4.23.0
+            self.controller.create, self.req, body=body)
 
     def test_keypair_create_with_name_too_long(self):
         body = {
@@ -138,9 +125,9 @@ class KeypairsTestV21(test.TestCase):
                 'name': 'a' * 256
             }
         }
-        self._test_keypair_create_bad_request_case(body,
-                                                   self.validation_error,
-                                                   'is too long')
+        self.assertRaisesRegex(
+            exception.ValidationError, 'is too long',
+            self.controller.create, self.req, body=body)
 
     def test_keypair_create_with_name_leading_trailing_spaces(self):
         body = {
@@ -149,9 +136,9 @@ class KeypairsTestV21(test.TestCase):
             }
         }
         expected_msg = 'Can not start or end with whitespace.'
-        self._test_keypair_create_bad_request_case(body,
-                                                   self.validation_error,
-                                                   expected_msg)
+        self.assertRaisesRegex(
+            exception.ValidationError, expected_msg,
+            self.controller.create, self.req, body=body)
 
     def test_keypair_create_with_name_leading_trailing_spaces_compat_mode(
             self):
@@ -166,10 +153,10 @@ class KeypairsTestV21(test.TestCase):
                 'name': 'test/keypair'
             }
         }
-        expected_msg = 'Only expected characters'
-        self._test_keypair_create_bad_request_case(body,
-                                                   self.validation_error,
-                                                   expected_msg)
+        expected_msg = 'Invalid input for field/attribute name.'
+        self.assertRaisesRegex(
+            exception.ValidationError, expected_msg,
+            self.controller.create, self.req, body=body)
 
     def test_keypair_create_with_special_characters(self):
         body = {
@@ -177,10 +164,10 @@ class KeypairsTestV21(test.TestCase):
                 'name': keypair_name_2_92_compatible
             }
         }
-        expected_msg = 'Only expected characters'
-        self._test_keypair_create_bad_request_case(body,
-                                                   self.validation_error,
-                                                   expected_msg)
+        expected_msg = 'Invalid input for field/attribute name.'
+        self.assertRaisesRegex(
+            exception.ValidationError, expected_msg,
+            self.controller.create, self.req, body=body)
 
     def test_keypair_import_bad_key(self):
         body = {
@@ -189,15 +176,16 @@ class KeypairsTestV21(test.TestCase):
                 'public_key': 'ssh-what negative',
             },
         }
-        self._test_keypair_create_bad_request_case(body,
-                                                   webob.exc.HTTPBadRequest)
+        self.assertRaises(
+            webob.exc.HTTPBadRequest, self.controller.create, self.req,
+            body=body)
 
     def test_keypair_create_with_invalid_keypair_body(self):
         body = {'alpha': {'name': 'create_test'}}
         expected_msg = "'keypair' is a required property"
-        self._test_keypair_create_bad_request_case(body,
-                                                   self.validation_error,
-                                                   expected_msg)
+        self.assertRaisesRegex(
+            exception.ValidationError, expected_msg,
+            self.controller.create, self.req, body=body)
 
     def test_keypair_import(self):
         body = {
diff --git a/nova/tests/unit/test_api_validation.py b/nova/tests/unit/test_api_validation.py
index b9b408f0cb..357e9bb5e2 100644
--- a/nova/tests/unit/test_api_validation.py
+++ b/nova/tests/unit/test_api_validation.py
@@ -731,33 +731,6 @@ class NameWithLeadingTrailingSpacesTestCase(APIValidationTestCase):
             pass
 
 
-class NoneTypeTestCase(APIValidationTestCase):
-
-    post_schema = {
-        'type': 'object',
-        'properties': {
-            'foo': parameter_types.none
-        }
-    }
-
-    def test_validate_none(self):
-        self.post(body={'foo': 'None'}, req=FakeRequest())
-        self.post(body={'foo': None}, req=FakeRequest())
-        self.post(body={'foo': {}}, req=FakeRequest())
-
-    def test_validate_none_fails(self):
-        detail = ("Invalid input for field/attribute foo. Value: ."
-                  " '' is not one of ['None', None, {}]")
-        self.check_validation_error(self.post, body={'foo': ''},
-                                    expected_detail=detail)
-
-        detail = ("Invalid input for field/attribute foo. Value: "
-                  "{'key': 'val'}. {'key': 'val'} is not one of "
-                  "['None', None, {}]")
-        self.check_validation_error(self.post, body={'foo': {'key': 'val'}},
-                                    expected_detail=detail)
-
-
 class NameOrNoneTestCase(APIValidationTestCase):
 
     post_schema = {