masto-fe/app/models/trends/base.rb
Eugen Rochko 6476f7e4da
Change trending statuses to only show one status from each account ()
Calculate trends in temporary sets to avoid having to manage items
that go below the decay threshold while not having any moments
where a half-processed set is accessible to end-users
2022-04-29 22:42:42 +02:00

101 lines
2.8 KiB
Ruby

# frozen_string_literal: true
class Trends::Base
include Redisable
include LanguagesHelper
class_attribute :default_options
attr_reader :options
# @param [Hash] options
# @option options [Integer] :threshold Minimum amount of uses by unique accounts to begin calculating the score
# @option options [Integer] :review_threshold Minimum rank (lower = better) before requesting a review
# @option options [ActiveSupport::Duration] :max_score_cooldown For this amount of time, the peak score (if bigger than current score) is decayed-from
# @option options [ActiveSupport::Duration] :max_score_halflife How quickly a peak score decays
def initialize(options = {})
@options = self.class.default_options.merge(options)
end
def register(_status)
raise NotImplementedError
end
def add(*)
raise NotImplementedError
end
def refresh(*)
raise NotImplementedError
end
def request_review
raise NotImplementedError
end
def query
Trends::Query.new(key_prefix, klass)
end
def score(id, locale: nil)
redis.zscore([key_prefix, 'all', locale].compact.join(':'), id) || 0
end
def rank(id, locale: nil)
redis.zrevrank([key_prefix, 'allowed', locale].compact.join(':'), id)
end
def currently_trending_ids(allowed, limit)
redis.zrevrange(allowed ? "#{key_prefix}:allowed" : "#{key_prefix}:all", 0, limit.positive? ? limit - 1 : limit).map(&:to_i)
end
protected
def key_prefix
raise NotImplementedError
end
def recently_used_ids(at_time = Time.now.utc)
redis.smembers(used_key(at_time)).map(&:to_i)
end
def record_used_id(id, at_time = Time.now.utc)
redis.sadd(used_key(at_time), id)
redis.expire(used_key(at_time), 1.day.seconds)
end
def score_at_rank(rank)
redis.zrevrange("#{key_prefix}:allowed", 0, rank, with_scores: true).last&.last || 0
end
def replace_items(suffix, items)
tmp_prefix = "#{key_prefix}:tmp:#{SecureRandom.alphanumeric(6)}#{suffix}"
allowed_items = filter_for_allowed_items(items)
redis.pipelined do |pipeline|
items.each { |item| pipeline.zadd("#{tmp_prefix}:all", item[:score], item[:item].id) }
allowed_items.each { |item| pipeline.zadd("#{tmp_prefix}:allowed", item[:score], item[:item].id) }
rename_set(pipeline, "#{tmp_prefix}:all", "#{key_prefix}:all#{suffix}", items)
rename_set(pipeline, "#{tmp_prefix}:allowed", "#{key_prefix}:allowed#{suffix}", allowed_items)
end
end
def filter_for_allowed_items(items)
raise NotImplementedError
end
private
def used_key(at_time)
"#{key_prefix}:used:#{at_time.beginning_of_day.to_i}"
end
def rename_set(pipeline, from_key, to_key, set_items)
if set_items.empty?
pipeline.del(to_key)
else
pipeline.rename(from_key, to_key)
end
end
end