<%= generate_error flash[:error] %>
<%= form_for(:session, url: login_path, html: { class: 'form session-form' }) do |f| %>

Please Login

<%= f.label :user_name, "User Name" %>
<%= f.text_field :user_name, value: params[:session] ? params[:session][:user_name] : "", size: 20, class: 'form-control' %>
<%= f.label :password, "Password" %>
<%= f.password_field :password, size: 20, class: 'form-control' %>
<%= f.submit "Login", class: 'btn btn-primary', data: { 'disable-with' => 'Processing...' } %> <% end %>