I am trying to upgrade my rails app to rails version 4.2.10 from rails version 4.2.5 . I am using react for the front end.
What I did was:
First I remove the line gem 'rails', '~> 4.2.5' from gemfile.
Second add the line gem 'rails', '~> 4.2.10' to gemfile.
Then created a new gemset (gemset create app_name_rails_4.2.10)
gemset use app_name_rails_4.2.10.
Deleted the gemfile.lock
Then run bundle install.
After that when I start the serever ,
I am getting error in console is -----
Response to preflight request doesn't pass access control check: The value of the 'Access-Control-Allow-Credentials' header in the response is '' which must be 'true' when the request's credentials mode is 'include'.