require 'mini_racer' require 'nokogiri' require 'erb' require_dependency 'url_helper' require_dependency 'excerpt_parser' require_dependency 'post' require_dependency 'discourse_tagging' require_dependency 'pretty_text/helpers' module PrettyText @mutex = Mutex.new @ctx_init = Mutex.new def self.app_root Rails.root end def self.find_file(root, filename) return filename if File.file?("#{root}#{filename}") es6_name = "#{filename}.js.es6" return es6_name if File.file?("#{root}#{es6_name}") js_name = "#{filename}.js" return js_name if File.file?("#{root}#{js_name}") erb_name = "#{filename}.js.es6.erb" return erb_name if File.file?("#{root}#{erb_name}") end def self.apply_es6_file(ctx, root_path, part_name) filename = find_file(root_path, part_name) if filename source = File.read("#{root_path}#{filename}") if filename =~ /\.erb$/ source = ERB.new(source).result(binding) end template = Tilt::ES6ModuleTranspilerTemplate.new {} transpiled = template.module_transpile(source, "#{Rails.root}/app/assets/javascripts/", part_name) ctx.eval(transpiled) else # Look for vendored stuff vendor_root = "#{Rails.root}/vendor/assets/javascripts/" filename = find_file(vendor_root, part_name) if filename ctx.eval(File.read("#{vendor_root}#{filename}")) end end end def self.ctx_load_manifest(ctx, name) manifest = File.read("#{Rails.root}/app/assets/javascripts/#{name}") root_path = "#{Rails.root}/app/assets/javascripts/" manifest.each_line do |l| l = l.chomp if l =~ /\/\/= require (\.\/)?(.*)$/ apply_es6_file(ctx, root_path, Regexp.last_match[2]) elsif l =~ /\/\/= require_tree (\.\/)?(.*)$/ path = Regexp.last_match[2] Dir["#{root_path}/#{path}/**"].sort.each do |f| apply_es6_file(ctx, root_path, f.sub(root_path, '')[1..-1].sub(/\.js.es6$/, '')) end end end end def self.create_es6_context ctx = MiniRacer::Context.new(timeout: 15000) ctx.eval("window = {}; window.devicePixelRatio = 2;") # hack to make code think stuff is retina if Rails.env.development? || Rails.env.test? ctx.attach("console.log", proc { |l| p l }) ctx.eval('window.console = console;') end ctx_load(ctx, "#{Rails.root}/app/assets/javascripts/discourse-loader.js") ctx_load(ctx, "vendor/assets/javascripts/lodash.js") ctx_load_manifest(ctx, "pretty-text-bundle.js") ctx_load_manifest(ctx, "markdown-it-bundle.js") root_path = "#{Rails.root}/app/assets/javascripts/" apply_es6_file(ctx, root_path, "discourse/lib/utilities") PrettyText::Helpers.instance_methods.each do |method| ctx.attach("__helpers.#{method}", PrettyText::Helpers.method(method)) end ctx.load("#{Rails.root}/lib/pretty_text/shims.js") ctx.eval("__setUnicode(#{Emoji.unicode_replacements_json})") to_load = [] DiscoursePluginRegistry.each_globbed_asset do |a| to_load << a if File.file?(a) && a =~ /discourse-markdown/ end to_load.uniq.each do |f| if f =~ /^.+assets\/javascripts\// root = Regexp.last_match[0] apply_es6_file(ctx, root, f.sub(root, '').sub(/\.js\.es6$/, '')) end end DiscoursePluginRegistry.vendored_pretty_text.each do |vpt| ctx.eval(File.read(vpt)) end ctx end def self.v8 return @ctx if @ctx # ensure we only init one of these @ctx_init.synchronize do return @ctx if @ctx @ctx = create_es6_context end @ctx end def self.reset_context @ctx_init.synchronize do @ctx&.dispose @ctx = nil end end def self.markdown(text, opts = {}) # we use the exact same markdown converter as the client # TODO: use the same extensions on both client and server (in particular the template for mentions) baked = nil text = text || "" protect do context = v8 paths = { baseUri: Discourse::base_uri, CDN: Rails.configuration.action_controller.asset_host, } if SiteSetting.enable_s3_uploads? if SiteSetting.s3_cdn_url.present? paths[:S3CDN] = SiteSetting.s3_cdn_url end paths[:S3BaseUrl] = Discourse.store.absolute_base_url end custom_emoji = {} Emoji.custom.map { |e| custom_emoji[e.name] = e.url } buffer = <<~JS __optInput = {}; __optInput.siteSettings = #{SiteSetting.client_settings_json}; __paths = #{paths.to_json}; __optInput.getURL = __getURL; __optInput.getCurrentUser = __getCurrentUser; __optInput.lookupAvatar = __lookupAvatar; __optInput.getTopicInfo = __getTopicInfo; __optInput.categoryHashtagLookup = __categoryLookup; __optInput.mentionLookup = __mentionLookup; __optInput.customEmoji = #{custom_emoji.to_json}; __optInput.emojiUnicodeReplacer = __emojiUnicodeReplacer; __optInput.lookupInlineOnebox = __lookupInlineOnebox; #{opts[:linkify] == false ? "__optInput.linkify = false;" : ""} __optInput.censoredWords = #{WordWatcher.words_for_action(:censor).join('|').to_json}; JS if opts[:topicId] buffer << "__optInput.topicId = #{opts[:topicId].to_i};\n" end if opts[:user_id] buffer << "__optInput.userId = #{opts[:user_id].to_i};\n" end buffer << "__textOptions = __buildOptions(__optInput);\n" buffer << ("__pt = new __PrettyText(__textOptions);") # Be careful disabling sanitization. We allow for custom emails if opts[:sanitize] == false buffer << ('__pt.disableSanitizer();') end opts = context.eval(buffer) DiscourseEvent.trigger(:markdown_context, context) baked = context.eval("__pt.cook(#{text.inspect})") end # if baked.blank? && !(opts || {})[:skip_blank_test] # # we may have a js engine issue # test = markdown("a", skip_blank_test: true) # if test.blank? # Rails.logger.warn("Markdown engine appears to have crashed, resetting context") # reset_context # opts ||= {} # opts = opts.dup # opts[:skip_blank_test] = true # baked = markdown(text, opts) # end # end baked end # leaving this here, cause it invokes v8, don't want to implement twice def self.avatar_img(avatar_template, size) protect do v8.eval("__utils.avatarImg({size: #{size.inspect}, avatarTemplate: #{avatar_template.inspect}}, __getURL);") end end def self.unescape_emoji(title) return title unless SiteSetting.enable_emoji? set = SiteSetting.emoji_set.inspect protect do v8.eval("__performEmojiUnescape(#{title.inspect}, { getURL: __getURL, emojiSet: #{set} })") end end def self.cook(text, opts = {}) options = opts.dup # we have a minor inconsistency options[:topicId] = opts[:topic_id] working_text = text.dup begin sanitized = markdown(working_text, options) rescue MiniRacer::ScriptTerminatedError => e if SiteSetting.censored_pattern.present? Rails.logger.warn "Post cooking timed out. Clearing the censored_pattern setting and retrying." SiteSetting.censored_pattern = nil sanitized = markdown(working_text, options) else raise e end end doc = Nokogiri::HTML.fragment(sanitized) if !options[:omit_nofollow] && SiteSetting.add_rel_nofollow_to_user_content add_rel_nofollow_to_user_content(doc) end if SiteSetting.enable_s3_uploads && SiteSetting.s3_cdn_url.present? add_s3_cdn(doc) end doc.to_html end def self.add_s3_cdn(doc) doc.css("img").each do |img| next unless img["src"] img["src"] = Discourse.store.cdn_url(img["src"]) end end def self.add_rel_nofollow_to_user_content(doc) whitelist = [] domains = SiteSetting.exclude_rel_nofollow_domains whitelist = domains.split('|') if domains.present? site_uri = nil doc.css("a").each do |l| href = l["href"].to_s begin uri = URI(href) site_uri ||= URI(Discourse.base_url) if !uri.host.present? || uri.host == site_uri.host || uri.host.ends_with?("." << site_uri.host) || whitelist.any? { |u| uri.host == u || uri.host.ends_with?("." << u) } # we are good no need for nofollow else l["rel"] = "nofollow noopener" end rescue URI::InvalidURIError, URI::InvalidComponentError # add a nofollow anyway l["rel"] = "nofollow noopener" end end end class DetectedLink < Struct.new(:url, :is_quote); end def self.extract_links(html) links = [] doc = Nokogiri::HTML.fragment(html) # remove href inside quotes & elided part doc.css("aside.quote a, .elided a").each { |a| a["href"] = "" } # extract all links doc.css("a").each do |a| if a["href"].present? && a["href"][0] != "#".freeze links << DetectedLink.new(a["href"], false) end end # extract quotes doc.css("aside.quote[data-topic]").each do |aside| if aside["data-topic"].present? url = "/t/topic/#{aside["data-topic"]}" url << "/#{aside["data-post"]}" if aside["data-post"].present? links << DetectedLink.new(url, true) end end # extract Youtube links doc.css("div[data-youtube-id]").each do |div| if div["data-youtube-id"].present? links << DetectedLink.new("https://www.youtube.com/watch?v=#{div['data-youtube-id']}", false) end end links end def self.excerpt(html, max_length, options = {}) # TODO: properly fix this HACK in ExcerptParser without introducing XSS doc = Nokogiri::HTML.fragment(html) strip_image_wrapping(doc) html = doc.to_html ExcerptParser.get_excerpt(html, max_length, options) end def self.strip_links(string) return string if string.blank? # If the user is not basic, strip links from their bio fragment = Nokogiri::HTML.fragment(string) fragment.css('a').each { |a| a.replace(a.inner_html) } fragment.to_html end # Given a Nokogiri doc, convert all links to absolute def self.make_all_links_absolute(doc) site_uri = nil doc.css("a").each do |link| href = link["href"].to_s begin uri = URI(href) site_uri ||= URI(Discourse.base_url) link["href"] = "#{site_uri}#{link['href']}" unless uri.host.present? rescue URI::InvalidURIError, URI::InvalidComponentError # leave it end end end def self.strip_image_wrapping(doc) doc.css(".lightbox-wrapper .meta").remove end def self.format_for_email(html, post = nil) doc = Nokogiri::HTML.fragment(html) DiscourseEvent.trigger(:reduce_cooked, doc, post) strip_image_wrapping(doc) make_all_links_absolute(doc) doc.to_html end protected class JavaScriptError < StandardError attr_accessor :message, :backtrace def initialize(message, backtrace) @message = message @backtrace = backtrace end end def self.protect rval = nil @mutex.synchronize do rval = yield end rval end def self.ctx_load(ctx, *files) files.each do |file| ctx.load(app_root + file) end end end