Jsonschema validation: base schema framework

This patch adds a base jsonschema framework.

This patch follows the Nova-Schema-framework:
https://github.com/openstack/nova/tree/master/nova/api/validation

Partial-Implements: blueprint tosca-csar-mgmt-driver

Co-Author: Neha Alhat <neha.alhat@nttdata.com>
Change-Id: I6ffeaaffb92fa9949a439a049f3092878b884634

requirements.txt

@@ -10,6 +10,7 @@ anyjson>=0.3.3 # BSD
 Babel!=2.4.0,>=2.3.4 # BSD
 eventlet!=0.23.0,!=0.25.0,>=0.22.0 # MIT
 requests>=2.14.2 # Apache-2.0
+jsonschema>=2.6.0 # MIT
 keystonemiddleware>=4.17.0 # Apache-2.0
 kombu!=4.0.2,>=4.0.0 # BSD
 netaddr>=0.7.18 # BSD

tacker/api/schemas/vnf_packages.py

@@ -0,0 +1,50 @@
+# Copyright (C) 2019 NTT DATA
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Schema for vnf packages create API.
+
+"""
+
+from tacker.api.validation import parameter_types
+
+create = {
+    'type': 'object',
+    'properties': {
+        'userDefinedData': parameter_types.keyvalue_pairs
+    },
+    'additionalProperties': False,
+}
+
+upload_from_uri = {
+    'type': 'object',
+    'properties': {
+        'addressInformation': {
+            'type': 'string', 'minLength': 0,
+            'maxLength': 2048, 'format': 'uri'
+        },
+        'userName': {
+            'type': 'string', 'maxLength': 255,
+            'pattern': '^[a-zA-Z0-9-_]*$'
+        },
+        'password': {
+            # Allow to specify any string for strong password.
+            'type': 'string', 'maxLength': 255,
+        },
+
+    },
+    'required': ['addressInformation'],
+    'additionalProperties': False,
+}

tacker/api/validation/__init__.py

@@ -0,0 +1,51 @@
+# Copyright (C) 2019 NTT DATA
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Request Body validating middleware.
+
+"""
+
+import functools
+import webob
+
+from tacker.api.validation import validators
+
+
+def schema(request_body_schema):
+    """Register a schema to validate request body.
+
+    Registered schema will be used for validating request body just before
+    API method executing.
+
+    :param dict request_body_schema: a schema to validate request body
+
+    """
+
+    def add_validator(func):
+        @functools.wraps(func)
+        def wrapper(*args, **kwargs):
+            schema_validator = validators._SchemaValidator(
+                request_body_schema)
+            try:
+                schema_validator.validate(kwargs['body'])
+            except KeyError:
+                raise webob.exc.HTTPBadRequest(
+                    explanation=_("Malformed request body"))
+
+            return func(*args, **kwargs)
+        return wrapper
+
+    return add_validator

tacker/api/validation/parameter_types.py

@@ -0,0 +1,30 @@
+# Copyright (C) 2019 NTT DATA
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Common parameter types for validating request Body.
+
+"""
+
+
+keyvalue_pairs = {
+    'type': 'object',
+    'patternProperties': {
+        '^[a-zA-Z0-9-_:. /]{1,255}$': {
+            'type': 'string', 'maxLength': 255
+        }
+    },
+    'additionalProperties': False
+}

tacker/api/validation/validators.py

@@ -0,0 +1,105 @@
+# Copyright (C) 2019 NTT DATA
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Internal implementation of request Body validating middleware.
+
+"""
+
+import jsonschema
+from jsonschema import exceptions as jsonschema_exc
+import rfc3986
+import six
+
+from tacker.common import exceptions as exception
+
+
+@jsonschema.FormatChecker.cls_checks('uri')
+def _validate_uri(instance):
+    return rfc3986.is_valid_uri(instance, require_scheme=True,
+                                require_authority=True)
+
+
+class FormatChecker(jsonschema.FormatChecker):
+    """A FormatChecker can output the message from cause exception
+
+    We need understandable validation errors messages for users. When a
+    custom checker has an exception, the FormatChecker will output a
+    readable message provided by the checker.
+    """
+
+    def check(self, param_value, format):
+        """Check whether the param_value conforms to the given format.
+
+        :argument param_value: the param_value to check
+        :type: any primitive type (str, number, bool)
+        :argument str format: the format that param_value should conform to
+        :raises: :exc:`FormatError` if param_value does not conform to format
+        """
+
+        if format not in self.checkers:
+            return
+
+        # For safety reasons custom checkers can be registered with
+        # allowed exception types. Anything else will fall into the
+        # default formatter.
+        func, raises = self.checkers[format]
+        result, cause = None, None
+
+        try:
+            result = func(param_value)
+        except raises as e:
+            cause = e
+        if not result:
+            msg = "%r is not a %r" % (param_value, format)
+            raise jsonschema_exc.FormatError(msg, cause=cause)
+
+
+class _SchemaValidator(object):
+    """A validator class
+
+    This class is changed from Draft4Validator to validate minimum/maximum
+    value of a string number(e.g. '10'). This changes can be removed when
+    we tighten up the API definition and the XML conversion.
+    Also FormatCheckers are added for checking data formats which would be
+    passed through cinder api commonly.
+
+    """
+    validator_org = jsonschema.Draft4Validator
+
+    def __init__(self, schema):
+        validator_cls = jsonschema.validators.extend(self.validator_org,
+                                                     validators={})
+        format_checker = FormatChecker()
+        self.validator = validator_cls(schema, format_checker=format_checker)
+
+    def validate(self, *args, **kwargs):
+        try:
+            self.validator.validate(*args, **kwargs)
+        except jsonschema.ValidationError as ex:
+            if len(ex.path) > 0:
+                detail = _("Invalid input for field/attribute %(path)s."
+                           " Value: %(value)s. %(message)s") % {
+                    'path': ex.path.pop(), 'value': ex.instance,
+                    'message': ex.message
+                }
+            else:
+                detail = ex.message
+            raise exception.ValidationError(detail=detail)
+        except TypeError as ex:
+            # NOTE: If passing non string value to patternProperties parameter,
+            #       TypeError happens. Here is for catching the TypeError.
+            detail = six.text_type(ex)
+            raise exception.ValidationError(detail=detail)

tacker/common/exceptions.py

@@ -195,3 +195,7 @@ class DuplicateResourceName(TackerException):
 
 class DuplicateEntity(Conflict):
     message = _("%(_type)s already exist with given %(entry)s")
+
+
+class ValidationError(BadRequest):
+    message = "%(detail)s"