chinwagsocial/app/models/trends/base.rb
Eugen Rochko 6476f7e4da
Change trending statuses to only show one status from each account (#18181)
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