mastodon/app/controllers/follower_accounts_controller.rb

# frozen_string_literal: true

class FollowerAccountsController < ApplicationController
  include AccountControllerConcern

  def index
    @follows = Follow.where(target_account: @account).recent.page(params[:page]).per(FOLLOW_PER_PAGE).preload(:account)

    respond_to do |format|
      format.html

      format.json do
        render json: collection_presenter, serializer: ActivityPub::CollectionSerializer, adapter: ActivityPub::Adapter
      end
    end
  end

  private

  def collection_presenter
    ActivityPub::CollectionPresenter.new(
      id: account_followers_url(@account),
      type: :ordered,
      size: @account.followers_count,
      items: @follows.map { |f| ActivityPub::TagManager.instance.uri_for(f.account) }
    )
  end
end