Skip JSON format in rails generate scaffold

Just clone the file

https://github.com/rails/rails/blob/v5.2.2/railties/lib/rails/generators/rails/scaffold_controller/scaffold_controller_generator.rb

to your

lib/rails/generators/rails/scaffold_controller/templates/controller.rb

path in your application and customize what you want. Also, you can write your own generators for scaffolding ( http://guides.rubyonrails.org/generators.html ).

Comment out gem jbuilder in your Gemfile and respond_to blocks won't be generated.