chinwagsocial/app/models/trends/statuses.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

122 lines
3.2 KiB
Ruby

# frozen_string_literal: true
class Trends::Statuses < Trends::Base
PREFIX = 'trending_statuses'
self.default_options = {
threshold: 5,
review_threshold: 3,
score_halflife: 2.hours.freeze,
decay_threshold: 0.3,
}
class Query < Trends::Query
def filtered_for!(account)
@account = account
self
end
def filtered_for(account)
clone.filtered_for!(account)
end
private
def apply_scopes(scope)
if @account.nil?
scope
else
scope.not_excluded_by_account(@account).not_domain_blocked_by_account(@account)
end
end
end
def register(status, at_time = Time.now.utc)
add(status.proper, status.account_id, at_time) if eligible?(status.proper)
end
def add(status, _account_id, at_time = Time.now.utc)
# We rely on the total reblogs and favourites count, so we
# don't record which account did the what and when here
record_used_id(status.id, at_time)
end
def query
Query.new(key_prefix, klass)
end
def refresh(at_time = Time.now.utc)
statuses = Status.where(id: (recently_used_ids(at_time) + currently_trending_ids(false, -1)).uniq).includes(:account, :media_attachments)
calculate_scores(statuses, at_time)
end
def request_review
statuses = Status.where(id: currently_trending_ids(false, -1)).includes(:account)
statuses.filter_map do |status|
next unless would_be_trending?(status.id) && !status.trendable? && status.requires_review_notification?
status.account.touch(:requested_review_at)
status
end
end
protected
def key_prefix
PREFIX
end
def klass
Status
end
private
def eligible?(status)
status.public_visibility? && status.account.discoverable? && !status.account.silenced? && status.spoiler_text.blank? && !status.sensitive? && !status.reply?
end
def calculate_scores(statuses, at_time)
global_items = []
locale_items = Hash.new { |h, key| h[key] = [] }
statuses.each do |status|
expected = 1.0
observed = (status.reblogs_count + status.favourites_count).to_f
score = begin
if expected > observed || observed < options[:threshold]
0
else
((observed - expected)**2) / expected
end
end
decaying_score = score * (0.5**((at_time.to_f - status.created_at.to_f) / options[:score_halflife].to_f))
next unless decaying_score >= options[:decay_threshold]
global_items << { score: decaying_score, item: status }
locale_items[status.language] << { account_id: status.account_id, score: decaying_score, item: status } if valid_locale?(status.language)
end
replace_items('', global_items)
Trends.available_locales.each do |locale|
replace_items(":#{locale}", locale_items[locale])
end
end
def filter_for_allowed_items(items)
# Show only one status per account, pick the one with the highest score
# that's also eligible to trend
items.group_by { |item| item[:account_id] }.values.filter_map { |account_items| account_items.select { |item| item[:item].trendable? && item[:item].account.discoverable? }.max_by { |item| item[:score] } }
end
def would_be_trending?(id)
score(id) > score_at_rank(options[:review_threshold] - 1)
end
end