class TopicRetriever def initialize(embed_url, opts=nil) @embed_url = embed_url @opts = opts || {} end def retrieve perform_retrieve unless (invalid_host? || retrieved_recently?) end private def invalid_host? SiteSetting.normalized_embeddable_host != URI(@embed_url).host rescue URI::InvalidURIError # An invalid URI is an invalid host true end def retrieved_recently? # We can disable the throttle for some users, such as staff return false if @opts[:no_throttle] # Throttle other users to once every 60 seconds retrieved_key = "retrieved:#{@embed_url}" if $redis.setnx(retrieved_key, "1") $redis.expire(retrieved_key, 60) return false end true end def perform_retrieve # It's possible another process or job found the embed already. So if that happened bail out. return if TopicEmbed.where(embed_url: @embed_url).exists? # First check RSS if that is enabled if SiteSetting.feed_polling_enabled? Jobs::PollFeed.new.execute({}) return if TopicEmbed.where(embed_url: @embed_url).exists? end fetch_http end def fetch_http user = User.find_by(username_lower: SiteSetting.embed_by_username.downcase) return if user.blank? TopicEmbed.import_remote(user, @embed_url) end end