discourse/lib/post_revisor.rb

414 lines
11 KiB
Ruby

require "edit_rate_limiter"
class PostRevisor
# Helps us track changes to a topic.
#
# It's passed to `track_topic_fields` callbacks so they can record if they
# changed a value or not. This is needed for things like custom fields.
class TopicChanges
attr_reader :topic, :user
def initialize(topic, user)
@topic = topic
@user = user
@changed = {}
@errored = false
end
def errored?
@errored
end
def guardian
@guardian ||= Guardian.new(@user)
end
def record_change(field_name, previous_val, new_val)
return if previous_val == new_val
diff[field_name] = [previous_val, new_val]
end
def check_result(res)
@errored = true if !res
end
def diff
@diff ||= {}
end
end
POST_TRACKED_FIELDS = %w{raw cooked edit_reason user_id wiki post_type}
attr_reader :category_changed
def initialize(post, topic=nil)
@post = post
@topic = topic || post.topic
end
def self.tracked_topic_fields
@@tracked_topic_fields ||= {}
@@tracked_topic_fields
end
def self.track_topic_field(field, &block)
tracked_topic_fields[field] = block
# Define it in the serializer unless it already has been defined
unless PostRevisionSerializer.instance_methods(false).include?("#{field}_changes".to_sym)
PostRevisionSerializer.add_compared_field(field)
end
end
# Fields we want to record revisions for by default
track_topic_field(:title) do |tc, title|
tc.record_change('title', tc.topic.title, title)
tc.topic.title = title
end
track_topic_field(:category_id) do |tc, category_id|
tc.record_change('category_id', tc.topic.category_id, category_id)
tc.check_result(tc.topic.change_category_to_id(category_id))
end
# AVAILABLE OPTIONS:
# - revised_at: changes the date of the revision
# - force_new_version: bypass ninja-edit window
# - bypass_rate_limiter:
# - bypass_bump: do not bump the topic, even if last post
# - skip_validations: ask ActiveRecord to skip validations
def revise!(editor, fields, opts={})
@editor = editor
@fields = fields.with_indifferent_access
@opts = opts
@topic_changes = TopicChanges.new(@topic, editor)
# some normalization
@fields[:raw] = cleanup_whitespaces(@fields[:raw]) if @fields.has_key?(:raw)
@fields[:user_id] = @fields[:user_id].to_i if @fields.has_key?(:user_id)
@fields[:category_id] = @fields[:category_id].to_i if @fields.has_key?(:category_id)
# always reset edit_reason unless provided
@fields[:edit_reason] = nil unless @fields.has_key?(:edit_reason)
return false unless should_revise?
@post.acting_user = @editor
@topic.acting_user = @editor
@revised_at = @opts[:revised_at] || Time.now
@last_version_at = @post.last_version_at || Time.now
@version_changed = false
@post_successfully_saved = true
@validate_post = true
@validate_post = @opts[:validate_post] if @opts.has_key?(:validate_post)
@validate_post = !@opts[:skip_validations] if @opts.has_key?(:skip_validations)
@validate_topic = true
@validate_topic = @opts[:validate_topic] if @opts.has_key?(:validate_topic)
@validate_topic = !@opts[:validate_topic] if @opts.has_key?(:skip_validations)
Post.transaction do
revise_post
# TODO: these callbacks are being called in a transaction
# it is kind of odd, because the callback is called "before_edit"
# but the post is already edited at this point
# Trouble is that much of the logic of should I edit? is deeper
# down so yanking this in front of the transaction will lead to
# false positive.
plugin_callbacks
revise_topic
advance_draft_sequence
end
# WARNING: do not pull this into the transaction
# it can fire events in sidekiq before the post is done saving
# leading to corrupt state
post_process_post
update_topic_word_counts
alert_users
publish_changes
grant_badge
successfully_saved_post_and_topic
end
def cleanup_whitespaces(raw)
TextCleaner.normalize_whitespaces(raw).gsub(/\s+\z/, "")
end
def should_revise?
post_changed? || topic_changed?
end
def post_changed?
POST_TRACKED_FIELDS.each do |field|
return true if @fields.has_key?(field) && @fields[field] != @post.send(field)
end
false
end
def topic_changed?
PostRevisor.tracked_topic_fields.keys.any? {|f| @fields.has_key?(f)}
end
def revise_post
should_create_new_version? ? revise_and_create_new_version : revise
end
def should_create_new_version?
edited_by_another_user? || !ninja_edit? || owner_changed? || force_new_version?
end
def edited_by_another_user?
@post.last_editor_id != @editor.id
end
def ninja_edit?
@revised_at - @last_version_at <= SiteSetting.ninja_edit_window.to_i
end
def owner_changed?
@fields.has_key?(:user_id) && @fields[:user_id] != @post.user_id
end
def force_new_version?
@opts[:force_new_version] == true
end
def revise_and_create_new_version
@version_changed = true
@post.version += 1
@post.public_version += 1
@post.last_version_at = @revised_at
revise
perform_edit
bump_topic
end
def revise
update_post
update_topic if topic_changed?
create_or_update_revision
end
def update_post
prev_owner, new_owner = nil, nil
if @fields.has_key?("user_id") && @fields["user_id"] != @post.user_id
prev_owner = User.find_by_id(@post.user_id)
new_owner = User.find_by_id(@fields["user_id"])
UserAction.where( target_post_id: @post.id,
user_id: prev_owner.id,
action_type: [UserAction::NEW_TOPIC, UserAction::REPLY, UserAction::RESPONSE] )
.find_each { |ua| ua.destroy }
# UserActionObserver will create new UserAction records for the new owner
end
POST_TRACKED_FIELDS.each do |field|
@post.send("#{field}=", @fields[field]) if @fields.has_key?(field)
end
@post.last_editor_id = @editor.id
@post.word_count = @fields[:raw].scan(/\w+/).size if @fields.has_key?(:raw)
@post.self_edits += 1 if self_edit?
clear_flags_and_unhide_post
@post.extract_quoted_post_numbers
@post_successfully_saved = @post.save(validate: @validate_post)
@post.save_reply_relationships
# post owner changed
if prev_owner && new_owner && prev_owner != new_owner
likes = UserAction.where( target_post_id: @post.id,
user_id: prev_owner.id,
action_type: UserAction::WAS_LIKED ).update_all(user_id: new_owner.id)
prev_owner.user_stat.post_count -= 1
prev_owner.user_stat.topic_count -= 1 if @post.is_first_post?
prev_owner.user_stat.likes_received -= likes
prev_owner.user_stat.update_topic_reply_count
if @post.created_at == prev_owner.user_stat.first_post_created_at
prev_owner.user_stat.first_post_created_at = prev_owner.posts.order('created_at ASC').first.try(:created_at)
end
prev_owner.user_stat.save
new_owner.user_stat.post_count += 1
new_owner.user_stat.topic_count += 1 if @post.is_first_post?
new_owner.user_stat.likes_received += likes
new_owner.user_stat.update_topic_reply_count
new_owner.user_stat.save
end
end
def self_edit?
@editor == @post.user
end
def clear_flags_and_unhide_post
return unless editing_a_flagged_and_hidden_post?
PostAction.clear_flags!(@post, Discourse.system_user)
@post.unhide!
end
def editing_a_flagged_and_hidden_post?
self_edit? &&
@post.hidden &&
@post.hidden_reason_id == Post.hidden_reasons[:flag_threshold_reached]
end
def update_topic
Topic.transaction do
PostRevisor.tracked_topic_fields.each do |f, cb|
if !@topic_changes.errored? && @fields.has_key?(f)
cb.call(@topic_changes, @fields[f])
end
end
unless @topic_changes.errored?
@topic_changes.check_result(@topic.save(validate: @validate_topic))
end
end
end
def create_or_update_revision
# don't create an empty revision if something failed
return unless successfully_saved_post_and_topic
@version_changed ? create_revision : update_revision
end
def create_revision
modifications = post_changes.merge(@topic_changes.diff)
PostRevision.create!(
user_id: @post.last_editor_id,
post_id: @post.id,
number: @post.version,
modifications: modifications
)
end
def update_revision
return unless revision = PostRevision.find_by(post_id: @post.id, number: @post.version)
revision.user_id = @post.last_editor_id
modifications = post_changes.merge(@topic_changes.diff)
modifications.keys.each do |field|
if revision.modifications.has_key?(field)
old_value = revision.modifications[field][0]
new_value = modifications[field][1]
revision.modifications[field] = [old_value, new_value]
else
revision.modifications[field] = modifications[field]
end
end
revision.save if modifications.length
end
def post_changes
@post.previous_changes.slice(*POST_TRACKED_FIELDS)
end
def perform_edit
return if bypass_rate_limiter?
EditRateLimiter.new(@editor).performed!
end
def bypass_rate_limiter?
@opts[:bypass_rate_limiter] == true
end
def bump_topic
return if bypass_bump? || !is_last_post?
@topic.update_column(:bumped_at, Time.now)
TopicTrackingState.publish_latest(@topic)
end
def bypass_bump?
@opts[:bypass_bump] == true
end
def is_last_post?
!Post.where(topic_id: @topic.id)
.where("post_number > ?", @post.post_number)
.exists?
end
def plugin_callbacks
DiscourseEvent.trigger(:before_edit_post, @post)
DiscourseEvent.trigger(:validate_post, @post)
end
def revise_topic
return unless @post.post_number == 1
update_topic_excerpt
update_category_description
end
def update_topic_excerpt
excerpt = @post.excerpt(220, strip_links: true)
@topic.update_column(:excerpt, excerpt)
if @topic.archetype == "banner"
ApplicationController.banner_json_cache.clear
end
end
def update_category_description
return unless category = Category.find_by(topic_id: @topic.id)
body = @post.cooked
matches = body.scan(/\<p\>(.*)\<\/p\>/)
if matches && matches[0] && matches[0][0]
new_description = matches[0][0]
new_description = nil if new_description == I18n.t("category.replace_paragraph")
category.update_column(:description, new_description)
@category_changed = category
end
end
def advance_draft_sequence
@post.advance_draft_sequence
end
def post_process_post
@post.invalidate_oneboxes = true
@post.trigger_post_process
end
def update_topic_word_counts
Topic.exec_sql("UPDATE topics
SET word_count = (
SELECT SUM(COALESCE(posts.word_count, 0))
FROM posts
WHERE posts.topic_id = :topic_id
)
WHERE topics.id = :topic_id", topic_id: @topic.id)
end
def alert_users
PostAlerter.new.after_save_post(@post)
end
def publish_changes
@post.publish_change_to_clients!(:revised)
end
def grant_badge
BadgeGranter.queue_badge_grant(Badge::Trigger::PostRevision, post: @post)
end
def successfully_saved_post_and_topic
@post_successfully_saved && !@topic_changes.errored?
end
end