Exclude Accept, Content-type and Authorization header from OpenAPI do…

…cs (#504)

* Exclude Acccept, Content-type and Authorization header from the list of parameters

Based on the OpenAPI specs, some headers are not supposed to be listed directly as parameters https://swagger.io/docs/specification/describing-parameters/#header-parameters

---------

Co-authored-by: Roberto Prevato <roberto.prevato@gmail.com>

blacksheep/server/openapi/v3.py

@@ -861,7 +861,14 @@ def get_parameter_location_for_binder(
             return ParameterLocation.QUERY
         if isinstance(binder, CookieBinder):
             return ParameterLocation.COOKIE
-        if isinstance(binder, HeaderBinder):
+
+        # exclude those specific header value per documentation
+        # https://swagger.io/docs/specification/describing-parameters/#header-parameters
+        if isinstance(binder, HeaderBinder) and binder.parameter_name.lower() not in [
+            "content-type",
+            "accept",
+            "authorization",
+        ]:
             return ParameterLocation.HEADER
         return None