Use Request#raw_post instead Request#body

In order to get raw_post to be not empty after
ParamsParser#parse_formatted_parameters,
added rewinding of body stream input on parsing json params.

Closes #11345

1 files changed, 7 insertions, 0 deletions

diff --git a/actionpack/test/dispatch/request/json_params_parsing_test.rb b/actionpack/test/dispatch/request/json_params_parsing_test.rb
index b62ed6a8b2..dba9ab688f 100644
--- a/actionpack/test/dispatch/request/json_params_parsing_test.rb
+++ b/actionpack/test/dispatch/request/json_params_parsing_test.rb
@@ -70,6 +70,13 @@ class JsonParamsParsingTest < ActionDispatch::IntegrationTest
     end
   end
 
+  test 'raw_post is not empty for JSON request' do
+    with_test_routing do
+      post '/parse', '{"posts": [{"title": "Post Title"}]}', 'CONTENT_TYPE' => 'application/json'
+      assert_equal '{"posts": [{"title": "Post Title"}]}', request.raw_post
+    end
+  end
+
   private
     def assert_parses(expected, actual, headers = {})
       with_test_routing do