catstodon/app/lib/feed_manager.rb
Eugen Rochko ddd30f331c
Improve support for aspects/circles (#8950)
* Add silent column to mentions

* Save silent mentions in ActivityPub Create handler and optimize it

Move networking calls out of the database transaction

* Add "limited" visibility level masked as "private" in the API

Unlike DMs, limited statuses are pushed into home feeds. The access
control rules between direct and limited statuses is almost the same,
except for counter and conversation logic

* Ensure silent column is non-null, add spec

* Ensure filters don't check silent mentions for blocks/mutes

As those are "this person is also allowed to see" rather than "this
person is involved", therefore does not warrant filtering

* Clean up code

* Use Status#active_mentions to limit returned mentions

* Fix code style issues

* Use Status#active_mentions in Notification

And remove stream_entry eager-loading from Notification
2018-10-17 17:13:04 +02:00

305 lines
12 KiB
Ruby

# frozen_string_literal: true
require 'singleton'
class FeedManager
include Singleton
MAX_ITEMS = 400
# Must be <= MAX_ITEMS or the tracking sets will grow forever
REBLOG_FALLOFF = 40
def key(type, id, subtype = nil)
return "feed:#{type}:#{id}" unless subtype
"feed:#{type}:#{id}:#{subtype}"
end
def filter?(timeline_type, status, receiver_id)
if timeline_type == :home
filter_from_home?(status, receiver_id)
elsif timeline_type == :mentions
filter_from_mentions?(status, receiver_id)
else
false
end
end
def push_to_home(account, status)
return false unless add_to_feed(:home, account.id, status)
trim(:home, account.id)
PushUpdateWorker.perform_async(account.id, status.id, "timeline:#{account.id}") if push_update_required?("timeline:#{account.id}")
true
end
def unpush_from_home(account, status)
return false unless remove_from_feed(:home, account.id, status)
Redis.current.publish("timeline:#{account.id}", Oj.dump(event: :delete, payload: status.id.to_s))
true
end
def push_to_list(list, status)
return false if status.reply? && status.in_reply_to_account_id != status.account_id
return false unless add_to_feed(:list, list.id, status)
trim(:list, list.id)
PushUpdateWorker.perform_async(list.account_id, status.id, "timeline:list:#{list.id}") if push_update_required?("timeline:list:#{list.id}")
true
end
def unpush_from_list(list, status)
return false unless remove_from_feed(:list, list.id, status)
Redis.current.publish("timeline:list:#{list.id}", Oj.dump(event: :delete, payload: status.id.to_s))
true
end
def trim(type, account_id)
timeline_key = key(type, account_id)
reblog_key = key(type, account_id, 'reblogs')
# Remove any items past the MAX_ITEMS'th entry in our feed
redis.zremrangebyrank(timeline_key, '0', (-(FeedManager::MAX_ITEMS + 1)).to_s)
# Get the score of the REBLOG_FALLOFF'th item in our feed, and stop
# tracking anything after it for deduplication purposes.
falloff_rank = FeedManager::REBLOG_FALLOFF - 1
falloff_range = redis.zrevrange(timeline_key, falloff_rank, falloff_rank, with_scores: true)
falloff_score = falloff_range&.first&.last&.to_i || 0
# Get any reblogs we might have to clean up after.
redis.zrangebyscore(reblog_key, 0, falloff_score).each do |reblogged_id|
# Remove it from the set of reblogs we're tracking *first* to avoid races.
redis.zrem(reblog_key, reblogged_id)
# Just drop any set we might have created to track additional reblogs.
# This means that if this reblog is deleted, we won't automatically insert
# another reblog, but also that any new reblog can be inserted into the
# feed.
redis.del(key(type, account_id, "reblogs:#{reblogged_id}"))
end
end
def merge_into_timeline(from_account, into_account)
timeline_key = key(:home, into_account.id)
query = from_account.statuses.limit(FeedManager::MAX_ITEMS / 4)
if redis.zcard(timeline_key) >= FeedManager::MAX_ITEMS / 4
oldest_home_score = redis.zrange(timeline_key, 0, 0, with_scores: true)&.first&.last&.to_i || 0
query = query.where('id > ?', oldest_home_score)
end
query.each do |status|
next if status.direct_visibility? || status.limited_visibility? || filter?(:home, status, into_account)
add_to_feed(:home, into_account.id, status)
end
trim(:home, into_account.id)
end
def unmerge_from_timeline(from_account, into_account)
timeline_key = key(:home, into_account.id)
oldest_home_score = redis.zrange(timeline_key, 0, 0, with_scores: true)&.first&.last&.to_i || 0
from_account.statuses.select('id, reblog_of_id').where('id > ?', oldest_home_score).reorder(nil).find_each do |status|
remove_from_feed(:home, into_account.id, status)
end
end
def clear_from_timeline(account, target_account)
timeline_key = key(:home, account.id)
timeline_status_ids = redis.zrange(timeline_key, 0, -1)
target_statuses = Status.where(id: timeline_status_ids, account: target_account)
target_statuses.each do |status|
unpush_from_home(account, status)
end
end
def populate_feed(account)
added = 0
limit = FeedManager::MAX_ITEMS / 2
max_id = nil
loop do
statuses = Status.as_home_timeline(account)
.paginate_by_max_id(limit, max_id)
break if statuses.empty?
statuses.each do |status|
next if filter_from_home?(status, account)
added += 1 if add_to_feed(:home, account.id, status)
end
break unless added.zero?
max_id = statuses.last.id
end
end
private
def redis
Redis.current
end
def push_update_required?(timeline_id)
redis.exists("subscribed:#{timeline_id}")
end
def blocks_or_mutes?(receiver_id, account_ids, context)
Block.where(account_id: receiver_id, target_account_id: account_ids).any? ||
(context == :home ? Mute.where(account_id: receiver_id, target_account_id: account_ids).any? : Mute.where(account_id: receiver_id, target_account_id: account_ids, hide_notifications: true).any?)
end
def filter_from_home?(status, receiver_id)
return false if receiver_id == status.account_id
return true if status.reply? && (status.in_reply_to_id.nil? || status.in_reply_to_account_id.nil?)
return true if phrase_filtered?(status, receiver_id, :home)
check_for_blocks = status.active_mentions.pluck(:account_id)
check_for_blocks.concat([status.account_id])
if status.reblog?
check_for_blocks.concat([status.reblog.account_id])
check_for_blocks.concat(status.reblog.active_mentions.pluck(:account_id))
end
return true if blocks_or_mutes?(receiver_id, check_for_blocks, :home)
if status.reply? && !status.in_reply_to_account_id.nil? # Filter out if it's a reply
should_filter = !Follow.where(account_id: receiver_id, target_account_id: status.in_reply_to_account_id).exists? # and I'm not following the person it's a reply to
should_filter &&= receiver_id != status.in_reply_to_account_id # and it's not a reply to me
should_filter &&= status.account_id != status.in_reply_to_account_id # and it's not a self-reply
return should_filter
elsif status.reblog? # Filter out a reblog
should_filter = Follow.where(account_id: receiver_id, target_account_id: status.account_id, show_reblogs: false).exists? # if the reblogger's reblogs are suppressed
should_filter ||= Block.where(account_id: status.reblog.account_id, target_account_id: receiver_id).exists? # or if the author of the reblogged status is blocking me
should_filter ||= AccountDomainBlock.where(account_id: receiver_id, domain: status.reblog.account.domain).exists? # or the author's domain is blocked
return should_filter
end
false
end
def filter_from_mentions?(status, receiver_id)
return true if receiver_id == status.account_id
return true if phrase_filtered?(status, receiver_id, :notifications)
# This filter is called from NotifyService, but already after the sender of
# the notification has been checked for mute/block. Therefore, it's not
# necessary to check the author of the toot for mute/block again
check_for_blocks = status.active_mentions.pluck(:account_id)
check_for_blocks.concat([status.in_reply_to_account]) if status.reply? && !status.in_reply_to_account_id.nil?
should_filter = blocks_or_mutes?(receiver_id, check_for_blocks, :mentions) # Filter if it's from someone I blocked, in reply to someone I blocked, or mentioning someone I blocked (or muted)
should_filter ||= (status.account.silenced? && !Follow.where(account_id: receiver_id, target_account_id: status.account_id).exists?) # of if the account is silenced and I'm not following them
should_filter
end
def phrase_filtered?(status, receiver_id, context)
active_filters = Rails.cache.fetch("filters:#{receiver_id}") { CustomFilter.where(account_id: receiver_id).active_irreversible.to_a }.to_a
active_filters.select! { |filter| filter.context.include?(context.to_s) && !filter.expired? }
active_filters.map! do |filter|
if filter.whole_word
sb = filter.phrase =~ /\A[[:word:]]/ ? '\b' : ''
eb = filter.phrase =~ /[[:word:]]\z/ ? '\b' : ''
/(?mix:#{sb}#{Regexp.escape(filter.phrase)}#{eb})/
else
/#{Regexp.escape(filter.phrase)}/i
end
end
return false if active_filters.empty?
combined_regex = active_filters.reduce { |memo, obj| Regexp.union(memo, obj) }
status = status.reblog if status.reblog?
!combined_regex.match(Formatter.instance.plaintext(status)).nil? ||
(status.spoiler_text.present? && !combined_regex.match(status.spoiler_text).nil?)
end
# Adds a status to an account's feed, returning true if a status was
# added, and false if it was not added to the feed. Note that this is
# an internal helper: callers must call trim or push updates if
# either action is appropriate.
def add_to_feed(timeline_type, account_id, status)
timeline_key = key(timeline_type, account_id)
reblog_key = key(timeline_type, account_id, 'reblogs')
if status.reblog?
# If the original status or a reblog of it is within
# REBLOG_FALLOFF statuses from the top, do not re-insert it into
# the feed
rank = redis.zrevrank(timeline_key, status.reblog_of_id)
return false if !rank.nil? && rank < FeedManager::REBLOG_FALLOFF
reblog_rank = redis.zrevrank(reblog_key, status.reblog_of_id)
if reblog_rank.nil?
# This is not something we've already seen reblogged, so we
# can just add it to the feed (and note that we're
# reblogging it).
redis.zadd(timeline_key, status.id, status.id)
redis.zadd(reblog_key, status.id, status.reblog_of_id)
else
# Another reblog of the same status was already in the
# REBLOG_FALLOFF most recent statuses, so we note that this
# is an "extra" reblog, by storing it in reblog_set_key.
reblog_set_key = key(timeline_type, account_id, "reblogs:#{status.reblog_of_id}")
redis.sadd(reblog_set_key, status.id)
return false
end
else
# A reblog may reach earlier than the original status because of the
# delay of the worker deliverying the original status, the late addition
# by merging timelines, and other reasons.
# If such a reblog already exists, just do not re-insert it into the feed.
rank = redis.zrevrank(reblog_key, status.id)
return false unless rank.nil?
redis.zadd(timeline_key, status.id, status.id)
end
true
end
# Removes an individual status from a feed, correctly handling cases
# with reblogs, and returning true if a status was removed. As with
# `add_to_feed`, this does not trigger push updates, so callers must
# do so if appropriate.
def remove_from_feed(timeline_type, account_id, status)
timeline_key = key(timeline_type, account_id)
if status.reblog?
# 1. If the reblogging status is not in the feed, stop.
status_rank = redis.zrevrank(timeline_key, status.id)
return false if status_rank.nil?
# 2. Remove reblog from set of this status's reblogs.
reblog_set_key = key(timeline_type, account_id, "reblogs:#{status.reblog_of_id}")
redis.srem(reblog_set_key, status.id)
# 3. Re-insert another reblog or original into the feed if one
# remains in the set. We could pick a random element, but this
# set should generally be small, and it seems ideal to show the
# oldest potential such reblog.
other_reblog = redis.smembers(reblog_set_key).map(&:to_i).min
redis.zadd(timeline_key, other_reblog, other_reblog) if other_reblog
# 4. Remove the reblogging status from the feed (as normal)
# (outside conditional)
else
# If the original is getting deleted, no use for reblog references
redis.del(key(timeline_type, account_id, "reblogs:#{status.id}"))
end
redis.zrem(timeline_key, status.id)
end
end