miss template when respond CSV

Question

I have a action to download file csv, but when click error missing template

Code in my action

def export 
    respond_to do |format|
      format.html
      format.csv { send_data UserDetail.order('id desc').first(20).to_csv }
    end
  end

In my view:

= link_to "Export CSV", export_call_center_user_details_path(format: "csv"), :class => "btn btn-default"

error:

Processing by CallCenter::UserDetailsController#export as CSV Completed 500 Internal Server Error in 5ms

A ActionView::MissingTemplate occurred in user_details#export:

Missing template call_center/user_details/export, application/export with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder, :coffee, :haml]}.

When i try remove line format.html so error:

Completed 406 Not Acceptable in 4ms (ActiveRecord: 0.3ms)

How to fix error above?

update

error:

Started GET "/call_center/user_details/export.csv" for 127.0.0.1 at 2016-06-20 16:10:32 +0700 Processing by CallCenter::UserDetailsController#export as CSV Admin Load (0.3ms) SELECT admins.* FROM admins WHERE admins.id = 3 LIMIT 1 Completed 500 Internal Server Error in 53ms
Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/_request.text.erb (0.8ms) Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/_title.text.erb (0.3ms)
Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/_session.text.erb (1.0ms)
Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/_title.text.erb (0.1ms) Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/_environment.text.erb (9.5ms)
Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/_title.text.erb (0.1ms)
Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/_backtrace.text.erb (0.5ms)
Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/_title.text.erb (0.1ms)
Rendered /home/thekop/.rvm/gems/ruby-2.1.4/gems/exception_notification-2.6.1/lib/exception_notifier/views/exception_notifier/exception_notification.text.erb (21.4ms)

Sent mail to [email protected] (1404ms) Date: Mon, 20 Jun 2016 16:10:33 +0700 From: xxx To: [email protected] Message-ID: <[email protected]> Subject: [xxx xxx] user_details#export (ActionView::MissingTemplate) "Missing template call_center/user_details/e... Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit

A ActionView::MissingTemplate occurred in user_details#export:

Missing template call_center/user_details/export, application/export with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder, :coffee, :haml]}. Searched in: * "/home/thekop/rails/xxx/app/views/templates/xxx" * "/home/thekop/rails/xxx/app/views" * "/home/thekop/.rvm/gems/ruby-2.1.4/gems/devise-3.5.2/app/views" * "/home/thekop/.rvm/gems/ruby-2.1.4/gems/twitter-bootstrap-rails-2.2.4/app/views"

actionpack (3.2.13) lib/action_view/path_set.rb:58:in `find'

Answer 1

The first thing we need to do is open up the config/application.rb file and add:

require 'csv'

below the line that says:

require 'rails/all'

Next, we need to add some code to the model that will export the data in the CSV format. Add the following code to the model you wish to export to CSV:

def self.as_csv
  CSV.generate do |csv|
    csv << column_names
    all.each do |item|
      csv << item.attributes.values_at(*column_names)
    end
  end
end

This code will export both the column headers as well as the data in the csv format and return the result.

Finally, we need to add a bit of extra code to our controller in order to return the CSV data to our user. Assuming your model and controller are named posts, add the following code to your posts controller:

def index
  @details = UserDetail.order('id desc').first(20)

  respond_to do |format|
    format.html
    format.csv { send_data @details.as_csv }
  end
end

Credits: Check