Return a 422 response when a ValidationError is raised

closes #38

tests/test_bottleparser.py

@@ -62,7 +62,7 @@ def test_parsing_form_default(testapp):
 
 def test_abort_called_on_validation_error(testapp):
     res = testapp.post('/echo', {'name': 'b'}, expect_errors=True)
-    assert res.status_code == 400
+    assert res.status_code == 422
 
 def test_validation_error_with_status_code_and_data(app):
     def always_fail(value):
@@ -91,7 +91,7 @@ def echo(args):
     result = testapp.post('/foo/', {'myvalue': 43}, expect_errors=True)
     assert result.status_code == 200
     result = testapp.post('/foo/', {'myvalue': 41}, expect_errors=True)
-    assert result.status_code == 400
+    assert result.status_code == 422
 
 def test_use_args_with_url_params(app, testapp):
     @app.route('/foo/<name>')

tests/test_flaskparser.py

@@ -155,7 +155,7 @@ def validate(x):
         parser.parse(argmap)
     mock_abort.assert_called
     abort_args, abort_kwargs = mock_abort.call_args
-    assert abort_args[0] == 400
+    assert abort_args[0] == 422
     expected_msg = u'Validator {0}({1}) is not True'.format(validate.__name__, 41)
     assert abort_kwargs['message'] == expected_msg
     assert type(abort_kwargs['exc']) == ValidationError
@@ -189,7 +189,7 @@ def echo(args):
 
     test_client = testapp.test_client()
     res = test_client.post('/foo/', data={'myvalue': 41})
-    assert res.status_code == 400
+    assert res.status_code == 422
 
 
 def test_use_args_decorator_on_a_method(testapp):
@@ -296,7 +296,7 @@ def test_abort_called_when_required_arg_not_present(mock_abort, testapp):
     with testapp.test_request_context('/foo', method='post',
             data=json.dumps({}), content_type='application/json'):
         parser.parse(args)
-        assert mock_abort.called_once_with(400)
+        assert mock_abort.called_once_with(422)
 
 def test_arg_allowed_missing(testapp):
     # 'last' argument is allowed to be missing

tests/test_pyramidparser.py

@@ -123,7 +123,7 @@ def test_parse_files(testapp):
 
 def test_exception_on_validation_error(testapp):
     res = testapp.post('/validate', {'num': '3'}, expect_errors=True)
-    assert res.status_code == 400
+    assert res.status_code == 422
 
 def test_validation_error_with_message(testapp):
     res = testapp.post('/validate', {'num': '3'}, expect_errors=True)

tests/test_tornadoparser.py

@@ -625,14 +625,14 @@ def test_required_field_provided(self):
         json_body = parse_json(res.body)
         assert json_body['name'] == 'johnny'
 
-    def test_missing_required_field_throws_400(self):
+    def test_missing_required_field_throws_422(self):
         res = self.fetch(
             '/echo',
             method='POST',
             headers={'Content-Type': 'application/json'},
             body=json.dumps({'occupation': 'pizza'}),
         )
-        assert res.code == 400
+        assert res.code == 422
 
     def test_validation_error_with_status_code_and_extra_data(self):
         res = self.fetch(

webargs/core.py

@@ -40,7 +40,7 @@ class ValidationError(WebargsError):
 
         Store status_code and additonal data.
     """
-    def __init__(self, error, status_code=400, arg_name=None, **data):
+    def __init__(self, error, status_code=422, arg_name=None, **data):
         self.message = text_type(error)
         self.status_code = status_code
         self.arg_name = arg_name

webargs/tornadoparser.py

@@ -101,8 +101,12 @@ def handle_error(self, error):
         """
         logger.error(error)
         status_code = getattr(error, 'status_code', 400)
+        if status_code == 422:
+            reason = 'Unprocessable Entity'
+        else:
+            reason = None
         data = getattr(error, 'data', {})
-        raise tornado.web.HTTPError(status_code, error.args[0], **data)
+        raise tornado.web.HTTPError(status_code, error.args[0], reason=reason, **data)
 
     def use_args(self, argmap, req=None, locations=core.Parser.DEFAULT_LOCATIONS,
                  as_kwargs=False, validate=None):