discourse/app/models/search_observer.rb

150 lines
4.8 KiB
Ruby

require_dependency 'search'
class SearchObserver < ActiveRecord::Observer
observe :topic, :post, :user, :category
def self.scrub_html_for_search(html)
HtmlScrubber.scrub(html)
end
def self.update_index(table, id, raw_data)
raw_data = Search.prepare_data(raw_data)
table_name = "#{table}_search_data"
foreign_key = "#{table}_id"
# insert some extra words for I.am.a.word so "word" is tokenized
search_data = raw_data.gsub(/\p{L}*\.\p{L}*/) do |with_dot|
split = with_dot.split(".")
if split.length > 1
with_dot + (" " << split[1..-1].join(" "))
else
with_dot
end
end
# for user login and name use "simple" lowercase stemmer
stemmer = table == "user" ? "simple" : Search.long_locale
# Would be nice to use AR here but not sure how to execut Postgres functions
# when inserting data like this.
rows = Post.exec_sql_row_count("UPDATE #{table_name}
SET
raw_data = :raw_data,
locale = :locale,
search_data = TO_TSVECTOR('#{stemmer}', :search_data)
WHERE #{foreign_key} = :id",
raw_data: raw_data,
search_data: search_data,
id: id,
locale: SiteSetting.default_locale)
if rows == 0
Post.exec_sql("INSERT INTO #{table_name}
(#{foreign_key}, search_data, locale, raw_data)
VALUES (:id, TO_TSVECTOR('#{stemmer}', :search_data), :locale, :raw_data)",
raw_data: raw_data,
search_data: search_data,
id: id,
locale: SiteSetting.default_locale)
end
rescue
# don't allow concurrency to mess up saving a post
end
def self.update_topics_index(topic_id, title, cooked)
search_data = title.dup << " " << scrub_html_for_search(cooked)[0...Topic::MAX_SIMILAR_BODY_LENGTH]
update_index('topic', topic_id, search_data)
end
def self.update_posts_index(post_id, cooked, title, category)
search_data = scrub_html_for_search(cooked) << " " << title.dup.force_encoding('UTF-8')
search_data << " " << category if category
update_index('post', post_id, search_data)
end
def self.update_users_index(user_id, username, name)
search_data = username.dup << " " << (name || "")
update_index('user', user_id, search_data)
end
def self.update_categories_index(category_id, name)
update_index('category', category_id, name)
end
def self.index(obj)
if obj.class == Post && obj.cooked_changed?
if obj.topic
category_name = obj.topic.category.name if obj.topic.category
SearchObserver.update_posts_index(obj.id, obj.cooked, obj.topic.title, category_name)
SearchObserver.update_topics_index(obj.topic_id, obj.topic.title, obj.cooked) if obj.is_first_post?
else
Rails.logger.warn("Orphan post skipped in search_observer, topic_id: #{obj.topic_id} post_id: #{obj.id} raw: #{obj.raw}")
end
end
if obj.class == User && (obj.username_changed? || obj.name_changed?)
SearchObserver.update_users_index(obj.id, obj.username_lower || '', obj.name ? obj.name.downcase : '')
end
if obj.class == Topic && obj.title_changed?
if obj.posts
post = obj.posts.find_by(post_number: 1)
if post
category_name = obj.category.name if obj.category
SearchObserver.update_posts_index(post.id, post.cooked, obj.title, category_name)
SearchObserver.update_topics_index(obj.id, obj.title, post.cooked)
end
end
end
if obj.class == Category && obj.name_changed?
SearchObserver.update_categories_index(obj.id, obj.name)
end
end
def after_save(object)
SearchObserver.index(object)
end
class HtmlScrubber < Nokogiri::XML::SAX::Document
attr_reader :scrubbed
def initialize
@scrubbed = ""
end
def self.scrub(html)
me = new
parser = Nokogiri::HTML::SAX::Parser.new(me)
begin
copy = "<div>"
copy << html unless html.nil?
copy << "</div>"
parser.parse(html) unless html.nil?
end
me.scrubbed
end
def start_element(name, attributes=[])
attributes = Hash[*attributes.flatten]
if attributes["alt"]
scrubbed << " "
scrubbed << attributes["alt"]
scrubbed << " "
end
if attributes["title"]
scrubbed << " "
scrubbed << attributes["title"]
scrubbed << " "
end
end
def characters(string)
scrubbed << " "
scrubbed << string
scrubbed << " "
end
end
end