osem/app/controllers/admin/organizations_controller.rb

module Admin
  class OrganizationsController < Admin::BaseController
    load_and_authorize_resource :organization

    def index
      @organizations = Organization.all
    end

    def create
      @organization = Organization.new(organization_params)
      if @organization.save
        redirect_to admin_organizations_path,
                    notice: 'Organization successfully created'
      else
        redirect_to new_admin_organization_path,
                    error: @organization.errors.full_messages.join(', ')
      end
    end

    def new
      @organization = Organization.new
    end

    def edit; end

    def update
      if @organization.update_attributes(organization_params)
        redirect_to admin_organizations_path,
                    notice: 'Organization successfully updated'
      else
        redirect_to edit_admin_organization_path(@organization),
                    error: @organization.errors.full_messages.join(', ')
      end
    end

    def destroy
      if @organization.destroy
        redirect_to admin_organizations_path,
                    notice: 'Organization successfully destroyed'
      else
        redirect_to admin_organizations_path,
                    error: 'Organization cannot be destroyed'
      end
    end

    private

    def organization_params
      params.require(:organization).permit(:name, :description, :picture)
    end
  end
end