mastodon/app/lib/feed_manager.rb
aschmitz eeaec39888 Allow hiding of reblogs from followed users (#5762)
* Allow hiding of reblogs from followed users

This adds a new entry to the account menu to allow users to hide
future reblogs from a user (and then if they've done that, to show
future reblogs instead).

This does not remove or add historical reblogs from/to the user's
timeline; it only affects new statuses.

The API for this operates by sending a "reblogs" key to the follow
endpoint. If this is sent when starting a new follow, it will be
respected from the beginning of the follow relationship (even if
the follow request must be approved by the followee). If this is
sent when a follow relationship already exists, it will simply
update the existing follow relationship. As with the notification
muting, this will now return an object ({reblogs: [true|false]}) or
false for each follow relationship when requesting relationship
information for an account. This should cause few issues due to an
object being truthy in many languages, but some modifications may
need to be made in pickier languages.

Database changes: adds a show_reblogs column (default true,
non-nullable) to the follows and follow_requests tables. Because
these are non-nullable, we use the existing MigrationHelpers to
perform this change without locking those tables, although the
tables are likely to be small anyway.

Tests included.

See also <https://github.com/glitch-soc/mastodon/pull/212>.

* Rubocop fixes

* Code review changes

* Test fixes

This patchset closes #648 and resolves #3271.

* Rubocop fix

* Revert reblogs defaulting in argument, fix tests

It turns out we needed this for the same reason we needed it in muting:
if nil gets passed in somehow (most usually by an API client not passing
any value), we need to detect and handle it.

We could specify a default in the parameter and then also catch nil, but
there's no great reason to duplicate the default value.
2017-11-28 15:00:35 +01:00

263 lines
10 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 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? || 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 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?)
check_for_mutes = [status.account_id]
check_for_mutes.concat([status.reblog.account_id]) if status.reblog?
return true if Mute.where(account_id: receiver_id, target_account_id: check_for_mutes).any?
check_for_blocks = status.mentions.pluck(:account_id)
check_for_blocks.concat([status.reblog.account_id]) if status.reblog?
return true if Block.where(account_id: receiver_id, target_account_id: check_for_blocks).any?
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
check_for_blocks = [status.account_id]
check_for_blocks.concat(status.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 = Block.where(account_id: receiver_id, target_account_id: check_for_blocks).any? # Filter if it's from someone I blocked, in reply to someone I blocked, or mentioning someone I blocked
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
# 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
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).sort.first
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