```ruby
class PlacementGroupController < ApplicationController
  before_action :check_privileges
  before_action :get_session_data
  after_action :cleanup_action
  after_action :set_session_data

  include Mixins::GenericListMixin
  include Mixins::GenericSessionMixin
  include Mixins::MoreShowActions
  include Mixins::GenericShowMixin
  include Mixins::EmsCommon
  include Mixins::BreadcrumbsMixin

  def self.display_methods
    %w[instances]
  end

  def breadcrumb_name(_model)
    _("Placement Groups")
  end

  def self.table_name
    @table_name ||= "placement_group"
  end

  def download_data
    assert_privileges('flavor_show_list')
    super
  end

  def download_summary_pdf
    assert_privileges('flavor_show')
    super
  end

  private

  def textual_group_list
    [%i[relationships properties], %i[tags]]
  end
  helper_method :textual_group_list

  def breadcrumbs_options
    {
      :breadcrumbs => [
        {:title => _("Compute")},
        {:title => _("Clouds")},
        {:title => _("Placement Groups"), :url => controller_url},
      ],
    }
  end

  menu_section :clo
  feature_for_actions "#{controller_name}_show_list", *ADV_SEARCH_ACTIONS
end
```

Use placement_group features to assert privileges
user
```ruby
class PlacementGroupController < ApplicationController
  before_action :check_privileges
  before_action :get_session_data
  after_action :cleanup_action
  after_action :set_session_data

  include Mixins::GenericListMixin
  include Mixins::GenericSessionMixin
  include Mixins::MoreShowActions
  include Mixins::GenericShowMixin
  include Mixins::EmsCommon
  include Mixins::BreadcrumbsMixin

  def self.display_methods
    %w[instances]
  end

  def breadcrumb_name(_model)
    _("Placement Groups")
  end

  def self.table_name
    @table_name ||= "placement_group"
  end

  def download_data
    assert_privileges('placement_group_view')
    super
  end

  def download_summary_pdf
    assert_privileges('placement_group_view')
    super
  end

  private

  def textual_group_list
    [%i[relationships properties], %i[tags]]
  end
  helper_method :textual_group_list

  def breadcrumbs_options
    {
      :breadcrumbs => [
        {:title => _("Compute")},
        {:title => _("Clouds")},
        {:title => _("Placement Groups"), :url => controller_url},
      ],
    }
  end

  menu_section :clo
  feature_for_actions "#{controller_name}_show_list", *ADV_SEARCH_ACTIONS
end
```
assistant