[MIS-E002] - Changed type¶
Rationale¶
Changing the type of a field is not backward compatible as a client using “old” Swagger specs will send the field with a different type leading the service to fail to validate the request. On the other end, if the object containing the updated field is used in the response, it will lead to unexpected client errors when parsing the response and/or using the updated property.
Mitigation¶
There are no best practices for this type of issue. The general recommended approach is: don’t do it and add a new field to the spec.
Example¶
Old Swagger Specs¶
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 | swagger: '2.0'
info:
title: Minimal Case of MIS-E002 Rule
version: '1.0'
paths:
/endpoint:
get:
responses:
default:
description: ''
schema:
properties:
property:
type: string
type: object
x-model: get_endpoint_response
post:
parameters:
- in: body
name: body
required: true
schema:
properties:
property:
type: string
type: object
responses:
default:
description: ''
|
New Swagger Specs¶
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 | swagger: '2.0'
info:
title: Minimal Case of MIS-E002 Rule
version: '1.0'
paths:
/endpoint:
get:
responses:
default:
description: ''
schema:
properties:
property:
type: boolean
type: object
x-model: get_endpoint_response
post:
parameters:
- in: body
name: body
required: true
schema:
properties:
property:
type: boolean
type: object
responses:
default:
description: ''
|
Backward Incompatibility¶
The following snippet triggers the incompatibility error.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 | # -*- coding: utf-8 -*-
from __future__ import absolute_import
from __future__ import print_function
from __future__ import unicode_literals
from os.path import abspath
from bravado.client import SwaggerClient
from bravado_core.validate import validate_schema_object
from jsonschema import ValidationError
from six.moves.urllib.parse import urljoin
from six.moves.urllib.request import pathname2url
old_client = SwaggerClient.from_url(
spec_url=urljoin('file:', pathname2url(abspath('old.yaml'))),
)
new_client = SwaggerClient.from_url(
spec_url=urljoin('file:', pathname2url(abspath('new.yaml'))),
)
object_to_validate = {'property': 'True'}
print('Validating the get endpoint response with old client: Succeeded')
validate_schema_object(
swagger_spec=old_client.swagger_spec,
schema_object_spec=old_client.swagger_spec.definitions['get_endpoint_response']._model_spec,
value=object_to_validate,
)
print('Validating the get endpoint response with the new client: Failed')
try:
validate_schema_object(
swagger_spec=new_client.swagger_spec,
schema_object_spec=new_client.swagger_spec.definitions['get_endpoint_response']._model_spec,
value=object_to_validate,
)
raise RuntimeError('An error was expected')
except ValidationError:
pass
print('Calling the post endpoint with old client: Succeeded')
old_client.endpoint.post_endpoint(body=object_to_validate)
print('Calling the post endpoint with the new client: Failed')
try:
new_client.endpoint.post_endpoint(body=object_to_validate)
except ValidationError:
pass
|
NOTE: The code is taking advantage of bravado