Fix/multiple content type headers lead to 415 consistently

connexion/utils.py

@@ -310,10 +310,8 @@ def extract_content_type(
 
         if decoded_key.lower() == "content-type":
             if isinstance(value, bytes):
-                content_type = value.decode("latin-1")
-            else:
-                content_type = value
-            break
+                value = value.decode("latin-1")
+            content_type = ",".join([content_type, value] if content_type else [value])
 
     return content_type
 

tests/test_json_validation.py

@@ -175,3 +175,26 @@ class MyDefaultsJSONBodyValidator(DefaultsJSONRequestBodyValidator):
     )
     assert res.status_code == 200
     assert res.json().get("human")
+
+
+def test_multiple_json_content_type(json_validation_spec_dir, spec):
+    """ensure that defaults applied that modify the body"""
+
+    class MyDefaultsJSONBodyValidator(DefaultsJSONRequestBodyValidator):
+        pass
+
+    validator_map = {"body": {"application/json": MyDefaultsJSONBodyValidator}}
+
+    app = App(__name__, specification_dir=json_validation_spec_dir)
+    app.add_api(spec, validate_responses=True, validator_map=validator_map)
+    app_client = app.test_client()
+
+    res = app_client.post(
+        "/v1.0/user",
+        data=json.dumps({"name": "foo"}),
+        headers={
+            "content-type": "application/json",
+            "Content-Type": "application/json",
+        },
+    )
+    assert res.status_code == 415