fix Werkzeug 2.1.x compatibility

- fix httpbin/core.py: use Responce class instead of BaseResponse
see: pallets/werkzeug#2276
- fix tests: TestClient doesn't provide 'Content-Length' header anymore
see: pallets/werkzeug#2347

httpbin/core.py

@@ -29,7 +29,7 @@
 from six.moves import range as xrange
 from werkzeug.datastructures import WWWAuthenticate, MultiDict
 from werkzeug.http import http_date
-from werkzeug.wrappers import BaseResponse
+from werkzeug.wrappers import Response
 from werkzeug.http import parse_authorization_header
 from flasgger import Swagger, NO_SANITIZER
 
@@ -77,7 +77,7 @@ def jsonify(*args, **kwargs):
 
 
 # Prevent WSGI from correcting the casing of the Location header
-BaseResponse.autocorrect_location_header = False
+Response.autocorrect_location_header = False
 
 # Find the correct template folder when running from a different location
 tmpl_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), "templates")

test_httpbin.py

@@ -148,7 +148,7 @@ def test_get(self):
         data = json.loads(response.data.decode('utf-8'))
         self.assertEqual(data['args'], {})
         self.assertEqual(data['headers']['Host'], 'localhost')
-        self.assertEqual(data['headers']['Content-Length'], '0')
+        # self.assertEqual(data['headers']['Content-Length'], '0')
         self.assertEqual(data['headers']['User-Agent'], 'test')
         # self.assertEqual(data['origin'], None)
         self.assertEqual(data['url'], 'http://localhost/get')
@@ -162,7 +162,7 @@ def test_anything(self):
         data = json.loads(response.data.decode('utf-8'))
         self.assertEqual(data['args'], {})
         self.assertEqual(data['headers']['Host'], 'localhost')
-        self.assertEqual(data['headers']['Content-Length'], '0')
+        # self.assertEqual(data['headers']['Content-Length'], '0')
         self.assertEqual(data['url'], 'http://localhost/anything/foo/bar')
         self.assertEqual(data['method'], 'GET')
         self.assertTrue(response.data.endswith(b'\n'))