mastodon/app/models/home_feed.rb

# frozen_string_literal: true

class HomeFeed < Feed
  def initialize(account)
    @account = account
    super(:home, account.id)
  end

  def async_refresh
    @async_refresh ||= AsyncRefresh.new(redis_regeneration_key)
  end

  def regenerating?
    async_refresh.running?
  rescue Redis::CommandError
    retry if upgrade_redis_key!
  end

  def regeneration_in_progress!
    @async_refresh = AsyncRefresh.create(redis_regeneration_key)
  rescue Redis::CommandError
    upgrade_redis_key!
  end

  def regeneration_finished!
    async_refresh.finish!
  rescue Redis::CommandError
    retry if upgrade_redis_key!
  end

  private

  def redis_regeneration_key
    @redis_regeneration_key = "account:#{@account.id}:regeneration"
  end

  def upgrade_redis_key!
    if redis.type(redis_regeneration_key) == 'string'
      redis.del(redis_regeneration_key)
      regeneration_in_progress!
      true
    end
  end
end