Excelizer

Excelizer handles Excel files generation for your Rails models with the Spreadsheet gem, using an API similar to the awesome active_model_serializers.

Installation

Add this line to your application's Gemfile:

gem 'excelizer'

And then execute:

$ bundle

Or install it yourself as:

$ gem install excelizer

You will need to add this line to the config/initializers/mime_types.rb file:

Mime::Type.register "application/vnd.ms-excel", :xls

Usage

You should create a downloaders folder inside the app folder. You can define a downloader like this

class UserDownloader < Excelizer::Base
  attr_downloadable :name, :last_name, :email, :birth_date
end

It's possible to redefine attributes using the @model reference 

class UserDownloader < Excelizer::Base
  attr_downloadable :name, :last_name, :email, :birth_date

  def name
    @model.name.titleize
  end

end

Or even create new attributes. Keep in mind new attributes will be added at the end of the row, but you can explicitly define the position where they should be. In this example, phone_number will go before birth_date while favorite_color will go after it.

class UserDownloader < Excelizer::Base
  attr_downloadable :name, :last_name, :email, :phone_number, :birth_date

  def phone_number
    '51' + @model.mobile_phone
  end

  def favorite_color
    @model.favorite_color || 'orange'
  end

end

Now that we have a downloader, how do we actually use it? If you want to learn how to use it along ActiveAdmin, skip to the next section, if you just want to use the raw data, you can do this:

raw_data = UserDownloader.new.build_xls

You can optionally pass a collection as a parameter for scoped results:

raw_data = UserDownloader.new.build_xls(User.where(name: 'James'))

ActiveAdmin

The recommended way to use this gem along ActiveAdmin is using an action_item and a collection_action. Future releases won't need this ;)

ActiveAdmin.register User do

  collection_action :download_xls do
    send_data UserDownloader.new.build_xls,
              type: 'application/vnd.ms-excel',
              filename: "user_report.xls"
  end

  action_item only: [:index] do
    link_to "Download Excel", download_xls_admin_users_path
  end

end

Contributing

  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request

Acknowledgments

Brought to you by Arturo Puente and the team at Phantasia.

Phantasia

Changelog

0.1.0 Custom header support.
0.0.9 Adds support for Rails 4.
0.0.8 Safer attribute initialization.
0.0.7 First release. Codename: Bond

License

This project is released under the MIT license.