ActiveModel::Exporters

ActiveModel::Exporters aims to provide an easy way to export collections of ActiveModel or ActiveRecord objects. It's based on object-oriented development and inspired on active_model_serializers.

Installation

Add this line to your application's Gemfile:

gem 'active_model_exporters'

And then execute:

$ bundle

Or install it yourself as:

$ gem install active_model_exporters

Usage

Generate an exporter in app/exporters/post_exporter.rb:

class PostExporter < ActiveModel::Exporter
  attributes :id, :title, :content
end

In your controller:

class PostsController < ApplicationController
  def index
    @posts = Post.all

    respond_to do |format|
      format.csv { render csv: @posts }
      format.xls { render xls: @posts }
    end
  end
end

Custom exporter

To specify a custom exporter for each object, you can do the next in your controller:

render csv: @posts, exporter: OtherPostExporter

Custom filename

By default filename is the pluralized collection type. Example: posts.xls. To specify another, you can do the next:

render xls: @posts, filename: 'super_posts.xls'

Custom encode format

By default encode format is iso-8859-1. You can change it doing the next:

render csv: @posts, encode: 'UTF-8'

Computed properties

As ActiveModel::Serializers does, you can access the object being exported as object.

class UserExporter < ActiveModel::Exporter
  attributes :first_name, :last_name, :full_name

  def full_name
    "#{object.first_name} #{object.last_name}"
  end
end

Exporter scope

1. Default scope

As ActiveModel::Serializers does, you can access to the current user via scope.

class UserExporter < ActiveModel::Exporter
  attributes :name, :email

  def email
    object.email unless scope.admin?
  end
end

2. Explicit scope

In your controller, include the scope option:

render csv: @posts, scope: current_admin

3. Calling exportation_scope

In your controller, set the exportation scope:

class PostsController < ApplicationController
  exportation_scope :current_admin

  def index
    # Do something...
  end
end

Filter attributes

As ActiveModel::Serializers does, you can reject some attributes according to your business rules:

class UserExporter < ActiveModel::Exporter
  attributes :name, :email, :address

  def filter(attrs)
    if object.admin?
      attrs - [:address]
    else
      attrs
    end
  end
end

Rejected attributes will be blank in the downloaded file.

Headers

ActiveModel::Exporters uses I18n translations in file headers.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/alejandrodevs/active_model_exporters. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the ActiveModel::Exporters project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.