Ruby on Rails datepicker
Use bootstrap datepicker gem
Gemfile:
gem 'bootstrap-datepicker-rails'
Add this line to app/assets/stylesheets/application.scss
*= require bootstrap-datepicker3
Add this line to app/assets/javascripts/application.js
//= require bootstrap-datepicker
Add this line to template
<%= f.text_field :publish_at, "data-provide" => 'datepicker', "data-date-format" => "yyyy-mm-dd" %>