discourse/lib/post_creator.rb
Sam 29fac1ac18 PERF: improve performance of unread queries
Figuring out what unread topics a user has is a very expensive
operation over time.

Users can easily accumulate 10s of thousands of tracking state rows
(1 for every topic they ever visit)

When figuring out what a user has that is unread we need to join
the tracking state records to the topic table. This can very quickly
lead to cases where you need to scan through the entire topic table.

This commit optimises it so we always keep track of the "first" date
a user has unread topics. Then we can easily filter out all earlier
topics from the join.

We use pg functions, instead of nested queries here to assist the
planner.
2017-05-25 15:07:30 -04:00

510 lines
17 KiB
Ruby

# Responsible for creating posts and topics
#
require_dependency 'rate_limiter'
require_dependency 'topic_creator'
require_dependency 'post_jobs_enqueuer'
require_dependency 'distributed_mutex'
require_dependency 'has_errors'
class PostCreator
include HasErrors
attr_reader :opts
# Acceptable options:
#
# raw - raw text of post
# image_sizes - We can pass a list of the sizes of images in the post as a shortcut.
# invalidate_oneboxes - Whether to force invalidation of oneboxes in this post
# acting_user - The user performing the action might be different than the user
# who is the post "author." For example when copying posts to a new
# topic.
# created_at - Post creation time (optional)
# auto_track - Automatically track this topic if needed (default true)
# custom_fields - Custom fields to be added to the post, Hash (default nil)
# post_type - Whether this is a regular post or moderator post.
# no_bump - Do not cause this post to bump the topic.
# cooking_options - Options for rendering the text
# cook_method - Method of cooking the post.
# :regular - Pass through Markdown parser and strip bad HTML
# :raw_html - Perform no processing
# :raw_email - Imported from an email
# via_email - Mark this post as arriving via email
# raw_email - Full text of arriving email (to store)
# action_code - Describes a small_action post (optional)
# skip_jobs - Don't enqueue jobs when creation succeeds. This is needed if you
# wrap `PostCreator` in a transaction, as the sidekiq jobs could
# dequeue before the commit finishes. If you do this, be sure to
# call `enqueue_jobs` after the transaction is comitted.
#
# When replying to a topic:
# topic_id - topic we're replying to
# reply_to_post_number - post number we're replying to
#
# When creating a topic:
# title - New topic title
# archetype - Topic archetype
# is_warning - Is the topic a warning?
# category - Category to assign to topic
# target_usernames - comma delimited list of usernames for membership (private message)
# target_group_names - comma delimited list of groups for membership (private message)
# meta_data - Topic meta data hash
# created_at - Topic creation time (optional)
# pinned_at - Topic pinned time (optional)
# pinned_globally - Is the topic pinned globally (optional)
#
def initialize(user, opts)
# TODO: we should reload user in case it is tainted, should take in a user_id as opposed to user
# If we don't do this we introduce a rather risky dependency
@user = user
@opts = opts || {}
opts[:title] = pg_clean_up(opts[:title]) if opts[:title] && opts[:title].include?("\u0000")
opts[:raw] = pg_clean_up(opts[:raw]) if opts[:raw] && opts[:raw].include?("\u0000")
opts.delete(:reply_to_post_number) unless opts[:topic_id]
@guardian = opts[:guardian] if opts[:guardian]
@spam = false
end
def pg_clean_up(str)
str.gsub("\u0000", "")
end
# True if the post was considered spam
def spam?
@spam
end
def skip_validations?
@opts[:skip_validations]
end
def guardian
@guardian ||= Guardian.new(@user)
end
def valid?
@topic = nil
@post = nil
if @user.suspended? && !skip_validations?
errors[:base] << I18n.t(:user_is_suspended)
return false
end
# Make sure none of the users have muted the creator
names = @opts[:target_usernames]
if names.present? && !skip_validations? && !@user.staff?
users = User.where(username: names.split(',').flatten).pluck(:id, :username).to_h
MutedUser.where(user_id: users.keys, muted_user_id: @user.id).pluck(:user_id).each do |m|
errors[:base] << I18n.t(:not_accepting_pms, username: users[m])
end
return false if errors[:base].present?
end
if new_topic?
topic_creator = TopicCreator.new(@user, guardian, @opts)
return false unless skip_validations? || validate_child(topic_creator)
else
@topic = Topic.find_by(id: @opts[:topic_id])
if (@topic.blank? || !guardian.can_create?(Post, @topic))
errors[:base] << I18n.t(:topic_not_found)
return false
end
end
setup_post
return true if skip_validations?
if @post.has_host_spam?
@spam = true
errors[:base] << I18n.t(:spamming_host)
return false
end
DiscourseEvent.trigger :before_create_post, @post
DiscourseEvent.trigger :validate_post, @post
post_validator = Validators::PostValidator.new(skip_topic: true)
post_validator.validate(@post)
valid = @post.errors.blank?
add_errors_from(@post) unless valid
valid
end
def create
if valid?
transaction do
build_post_stats
create_topic
save_post
extract_links
store_unique_post_key
track_topic
update_topic_stats
update_topic_auto_close
update_user_counts
create_embedded_topic
ensure_in_allowed_users if guardian.is_staff?
unarchive_message
@post.advance_draft_sequence
@post.save_reply_relationships
end
end
if @post && errors.blank?
# update counters etc.
@post.topic.reload
publish
track_latest_on_category
enqueue_jobs unless @opts[:skip_jobs]
BadgeGranter.queue_badge_grant(Badge::Trigger::PostRevision, post: @post)
trigger_after_events(@post)
auto_close unless @opts[:import_mode]
end
if @post || @spam
handle_spam unless @opts[:import_mode]
end
@post
end
def create!
create
if !self.errors.full_messages.empty?
raise ActiveRecord::RecordNotSaved.new("Failed to create post: #{self.errors.full_messages}")
end
@post
end
def enqueue_jobs
return unless @post && !@post.errors.present?
PostJobsEnqueuer.new(@post, @topic, new_topic?, {import_mode: @opts[:import_mode]}).enqueue_jobs
end
def self.track_post_stats
Rails.env != "test".freeze || @track_post_stats
end
def self.track_post_stats=(val)
@track_post_stats = val
end
def self.create(user, opts)
PostCreator.new(user, opts).create
end
def self.create!(user, opts)
PostCreator.new(user, opts).create!
end
def self.before_create_tasks(post)
set_reply_info(post)
post.word_count = post.raw.scan(/[[:word:]]+/).size
whisper = post.post_type == Post.types[:whisper]
post.post_number ||= Topic.next_post_number(post.topic_id, post.reply_to_post_number.present?, whisper)
cooking_options = post.cooking_options || {}
cooking_options[:topic_id] = post.topic_id
post.cooked ||= post.cook(post.raw, cooking_options.symbolize_keys)
post.sort_order = post.post_number
post.last_version_at ||= Time.now
end
def self.set_reply_info(post)
return unless post.reply_to_post_number.present?
reply_info = Post.where(topic_id: post.topic_id, post_number: post.reply_to_post_number)
.select(:user_id, :post_type)
.first
if reply_info.present?
post.reply_to_user_id ||= reply_info.user_id
whisper_type = Post.types[:whisper]
post.post_type = whisper_type if reply_info.post_type == whisper_type
end
end
protected
def build_post_stats
if PostCreator.track_post_stats
draft_key = @topic ? "topic_#{@topic.id}" : "new_topic"
sequence = DraftSequence.current(@user, draft_key)
revisions = Draft.where(sequence: sequence,
user_id: @user.id,
draft_key: draft_key).pluck(:revisions).first || 0
@post.build_post_stat(
drafts_saved: revisions,
typing_duration_msecs: @opts[:typing_duration_msecs] || 0,
composer_open_duration_msecs: @opts[:composer_open_duration_msecs] || 0
)
end
end
def trigger_after_events(post)
DiscourseEvent.trigger(:topic_created, post.topic, @opts, @user) unless @opts[:topic_id]
DiscourseEvent.trigger(:post_created, post, @opts, @user)
end
def auto_close
if @post.topic.private_message? &&
!@post.topic.closed &&
SiteSetting.auto_close_messages_post_count > 0 &&
SiteSetting.auto_close_messages_post_count <= @post.topic.posts_count
@post.topic.update_status(:closed, true, Discourse.system_user,
message: I18n.t('topic_statuses.autoclosed_message_max_posts', count: SiteSetting.auto_close_messages_post_count))
elsif !@post.topic.private_message? &&
!@post.topic.closed &&
SiteSetting.auto_close_topics_post_count > 0 &&
SiteSetting.auto_close_topics_post_count <= @post.topic.posts_count
@post.topic.update_status(:closed, true, Discourse.system_user,
message: I18n.t('topic_statuses.autoclosed_topic_max_posts', count: SiteSetting.auto_close_topics_post_count))
end
end
def transaction(&blk)
Post.transaction do
if new_topic?
blk.call
else
# we need to ensure post_number is monotonically increasing with no gaps
# so we serialize creation to avoid needing rollbacks
DistributedMutex.synchronize("topic_id_#{@opts[:topic_id]}", &blk)
end
end
end
# You can supply an `embed_url` for a post to set up the embedded relationship.
# This is used by the wp-discourse plugin to associate a remote post with a
# discourse post.
def create_embedded_topic
return unless @opts[:embed_url].present?
embed = TopicEmbed.new(topic_id: @post.topic_id, post_id: @post.id, embed_url: @opts[:embed_url])
rollback_from_errors!(embed) unless embed.save
end
def handle_spam
if @spam
GroupMessage.create( Group[:moderators].name,
:spam_post_blocked,
{ user: @user,
limit_once_per: 24.hours,
message_params: {domains: @post.linked_hosts.keys.join(', ')} } )
elsif @post && errors.blank? && !skip_validations?
SpamRulesEnforcer.enforce!(@post)
end
end
def track_latest_on_category
return unless @post && @post.errors.count == 0 && @topic && @topic.category_id
Category.where(id: @topic.category_id).update_all(latest_post_id: @post.id)
Category.where(id: @topic.category_id).update_all(latest_topic_id: @topic.id) if @post.is_first_post?
end
def ensure_in_allowed_users
return unless @topic.private_message? && @topic.id
unless @topic.topic_allowed_users.where(user_id: @user.id).exists?
unless @topic.topic_allowed_groups.where('group_id IN (
SELECT group_id FROM group_users where user_id = ?
)',@user.id).exists?
@topic.topic_allowed_users.create!(user_id: @user.id)
end
end
end
def unarchive_message
return unless @topic.private_message? && @topic.id
UserArchivedMessage.where(topic_id: @topic.id).pluck(:user_id).each do |user_id|
UserArchivedMessage.move_to_inbox!(user_id, @topic.id)
end
GroupArchivedMessage.where(topic_id: @topic.id).pluck(:group_id).each do |group_id|
GroupArchivedMessage.move_to_inbox!(group_id, @topic.id)
end
end
private
# TODO: merge the similar function in TopicCreator and fix parameter naming for `category`
def find_category_id
@opts.delete(:category) if @opts[:archetype].present? && @opts[:archetype] == Archetype.private_message
category = if (@opts[:category].is_a? Integer) || (@opts[:category] =~ /^\d+$/)
Category.find_by(id: @opts[:category])
else
Category.find_by(name_lower: @opts[:category].try(:downcase))
end
category&.id
end
def create_topic
return if @topic
begin
topic_creator = TopicCreator.new(@user, guardian, @opts)
@topic = topic_creator.create
rescue ActiveRecord::Rollback
rollback_from_errors!(topic_creator)
end
@post.topic_id = @topic.id
@post.topic = @topic
if @topic && @topic.category && @topic.category.all_topics_wiki
@post.wiki = true
end
end
def update_topic_stats
attrs = {last_unread_at: @post.created_at}
if @post.post_type != Post.types[:whisper]
attrs[:last_posted_at] = @post.created_at
attrs[:last_post_user_id] = @post.user_id
attrs[:word_count] = (@topic.word_count || 0) + @post.word_count
attrs[:excerpt] = @post.excerpt(220, strip_links: true) if new_topic?
attrs[:bumped_at] = @post.created_at unless @post.no_bump
end
@topic.update_attributes(attrs)
end
def update_topic_auto_close
topic_timer = @topic.public_topic_timer
if topic_timer &&
topic_timer.based_on_last_post &&
topic_timer.duration > 0
@topic.set_or_create_timer(TopicTimer.types[:close],
topic_timer.duration,
based_on_last_post: topic_timer.based_on_last_post
)
end
end
def setup_post
@opts[:raw] = TextCleaner.normalize_whitespaces(@opts[:raw] || '').gsub(/\s+\z/, "")
post = Post.new(raw: @opts[:raw],
topic_id: @topic.try(:id),
user: @user,
reply_to_post_number: @opts[:reply_to_post_number])
# Attributes we pass through to the post instance if present
[:post_type, :no_bump, :cooking_options, :image_sizes, :acting_user, :invalidate_oneboxes, :cook_method, :via_email, :raw_email, :action_code].each do |a|
post.send("#{a}=", @opts[a]) if @opts[a].present?
end
post.extract_quoted_post_numbers
post.created_at = Time.zone.parse(@opts[:created_at].to_s) if @opts[:created_at].present?
if fields = @opts[:custom_fields]
post.custom_fields = fields
end
@post = post
end
def save_post
@post.disable_rate_limits! if skip_validations?
saved = @post.save(validate: !skip_validations?)
rollback_from_errors!(@post) unless saved
end
def store_unique_post_key
@post.store_unique_post_key
end
def update_user_counts
return if @opts[:import_mode]
@user.create_user_stat if @user.user_stat.nil?
if @user.user_stat.first_post_created_at.nil?
@user.user_stat.first_post_created_at = @post.created_at
end
unless @post.topic.private_message?
@user.user_stat.post_count += 1
@user.user_stat.topic_count += 1 if @post.is_first_post?
end
# We don't count replies to your own topics
if !@opts[:import_mode] && @user.id != @topic.user_id
@user.user_stat.update_topic_reply_count
end
@user.user_stat.save!
@user.update_attributes(last_posted_at: @post.created_at)
end
def publish
return if @opts[:import_mode]
return unless @post.post_number > 1
@post.publish_change_to_clients! :created
end
def extract_links
TopicLink.extract_from(@post)
QuotedPost.extract_from(@post)
end
def track_topic
return if @opts[:auto_track] == false
unless @user.user_option.disable_jump_reply?
TopicUser.change(@post.user_id,
@topic.id,
posted: true,
last_read_post_number: @post.post_number,
highest_seen_post_number: @post.post_number)
# assume it took us 5 seconds of reading time to make a post
PostTiming.record_timing(topic_id: @post.topic_id,
user_id: @post.user_id,
post_number: @post.post_number,
msecs: 5000)
end
if @user.staged
TopicUser.auto_notification_for_staging(@user.id, @topic.id, TopicUser.notification_reasons[:auto_watch])
elsif @user.user_option.notification_level_when_replying === NotificationLevels.topic_levels[:watching]
TopicUser.auto_notification(@user.id, @topic.id, TopicUser.notification_reasons[:created_post], NotificationLevels.topic_levels[:watching])
elsif @user.user_option.notification_level_when_replying === NotificationLevels.topic_levels[:regular]
TopicUser.auto_notification(@user.id, @topic.id, TopicUser.notification_reasons[:created_post], NotificationLevels.topic_levels[:regular])
else
TopicUser.auto_notification(@user.id, @topic.id, TopicUser.notification_reasons[:created_post], NotificationLevels.topic_levels[:tracking])
end
end
def new_topic?
@opts[:topic_id].blank?
end
end