Merge pull request #215 from wasbazi/copy-before-validation

Copy spec before validation occurs

connexion/api.py

@@ -11,6 +11,7 @@
  language governing permissions and limitations under the License.
 """
 
+import copy
 import json
 import logging
 import pathlib
@@ -87,7 +88,10 @@ def __init__(self, swagger_yaml_path, base_url=None, arguments=None,
 
         logger.debug('Read specification', extra=self.specification)
 
-        validate_spec(compatibility_layer(self.specification))
+        self.specification = compatibility_layer(self.specification)
+        # Avoid validator having ability to modify specification
+        spec = copy.deepcopy(self.specification)
+        validate_spec(spec)
 
         # https://github.com/swagger-api/swagger-spec/blob/master/versions/2.0.md#fixed-fields
         # If base_url is not on provided then we try to read it from the swagger.yaml or use / by default