discourse/lib/oneboxer.rb

567 lines
18 KiB
Ruby

# frozen_string_literal: true
require 'uri'
Dir["#{Rails.root}/lib/onebox/engine/*_onebox.rb"].sort.each { |f| require f }
module Oneboxer
ONEBOX_CSS_CLASS = "onebox"
AUDIO_REGEX = /^\.(mp3|og[ga]|opus|wav|m4[abpr]|aac|flac)$/i
VIDEO_REGEX = /^\.(mov|mp4|webm|m4v|3gp|ogv|avi|mpeg|ogv)$/i
# keep reloaders happy
unless defined? Oneboxer::Result
Result = Struct.new(:doc, :changed) do
def to_html
doc.to_html
end
def changed?
changed
end
end
end
def self.ignore_redirects
@ignore_redirects ||= ['http://www.dropbox.com', 'http://store.steampowered.com', 'http://vimeo.com', 'https://www.youtube.com', Discourse.base_url]
end
def self.amazon_domains
amazon_suffixes = %w(com com.br ca cn fr de in it co.jp com.mx nl pl sa sg es se com.tr ae co.uk)
amazon_suffixes.collect { |suffix| "https://www.amazon.#{suffix}" }
end
def self.force_get_hosts
hosts = []
hosts += SiteSetting.force_get_hosts.split('|').collect { |domain| "https://#{domain}" }
hosts += SiteSetting.cache_onebox_response_body_domains.split('|').collect { |domain| "https://www.#{domain}" }
hosts += amazon_domains
hosts.uniq
end
def self.force_custom_user_agent_hosts
SiteSetting.force_custom_user_agent_hosts.split('|')
end
def self.allowed_post_types
@allowed_post_types ||= [Post.types[:regular], Post.types[:moderator_action]]
end
def self.preview(url, options = nil)
options ||= {}
invalidate(url) if options[:invalidate_oneboxes]
onebox_raw(url, options)[:preview]
end
def self.onebox(url, options = nil)
options ||= {}
invalidate(url) if options[:invalidate_oneboxes]
onebox_raw(url, options)[:onebox]
end
def self.cached_onebox(url)
if c = Discourse.cache.read(onebox_cache_key(url))
c[:onebox]
end
rescue => e
invalidate(url)
Rails.logger.warn("invalid cached onebox for #{url} #{e}")
""
end
def self.cached_preview(url)
if c = Discourse.cache.read(onebox_cache_key(url))
c[:preview]
end
rescue => e
invalidate(url)
Rails.logger.warn("invalid cached preview for #{url} #{e}")
""
end
def self.invalidate(url)
Discourse.cache.delete(onebox_cache_key(url))
Discourse.cache.delete(onebox_failed_cache_key(url))
end
def self.cache_response_body?(uri)
uri = URI.parse(uri) if uri.is_a?(String)
if SiteSetting.cache_onebox_response_body?
SiteSetting.cache_onebox_response_body_domains.split("|").any? { |domain| uri.hostname.ends_with?(domain) }
end
end
def self.cache_response_body(uri, response)
key = redis_cached_response_body_key(uri)
Discourse.redis.without_namespace.setex(key, 1.minutes.to_i, response)
end
def self.cached_response_body_exists?(uri)
key = redis_cached_response_body_key(uri)
Discourse.redis.without_namespace.exists(key).to_i > 0
end
def self.fetch_cached_response_body(uri)
key = redis_cached_response_body_key(uri)
Discourse.redis.without_namespace.get(key)
end
def self.redis_cached_response_body_key(uri)
"CACHED_RESPONSE_#{uri}"
end
# Parse URLs out of HTML, returning the document when finished.
def self.each_onebox_link(doc, extra_paths: [])
onebox_links = doc.css("a.#{ONEBOX_CSS_CLASS}", *extra_paths)
if onebox_links.present?
onebox_links.each do |link|
yield(link['href'], link) if link['href'].present?
end
end
doc
end
HTML5_BLOCK_ELEMENTS ||= %w{address article aside blockquote canvas center dd div dl dt fieldset figcaption figure footer form h1 h2 h3 h4 h5 h6 header hgroup hr li main nav noscript ol output p pre section table tfoot ul video}
def self.apply(string_or_doc, extra_paths: nil)
doc = string_or_doc
doc = Loofah.fragment(doc) if doc.is_a?(String)
changed = false
each_onebox_link(doc, extra_paths: extra_paths) do |url, element|
onebox, _ = yield(url, element)
next if onebox.blank?
parsed_onebox = Loofah.fragment(onebox)
next if parsed_onebox.children.blank?
changed = true
parent = element.parent
if parent&.node_name&.downcase == "p" &&
parsed_onebox.children.any? { |child| HTML5_BLOCK_ELEMENTS.include?(child.node_name.downcase) }
siblings = parent.children
element_idx = siblings.find_index(element)
before_idx = first_significant_element_index(siblings, element_idx - 1, -1)
after_idx = first_significant_element_index(siblings, element_idx + 1, +1)
if before_idx < 0 && after_idx >= siblings.size
parent.replace parsed_onebox
elsif before_idx < 0
parent.children = siblings[after_idx..siblings.size]
parent.add_previous_sibling(parsed_onebox)
elsif after_idx >= siblings.size
parent.children = siblings[0..before_idx]
parent.add_next_sibling(parsed_onebox)
else
parent_rest = parent.dup
parent.children = siblings[0..before_idx]
parent_rest.children = siblings[after_idx..siblings.size]
parent.add_next_sibling(parent_rest)
parent.add_next_sibling(parsed_onebox)
end
else
element.replace parsed_onebox
end
end
Result.new(doc, changed)
end
def self.first_significant_element_index(elements, index, step)
while index >= 0 && index < elements.size &&
(elements[index].node_name.downcase == "br" ||
(elements[index].node_name.downcase == "text" && elements[index].to_html.strip.blank?))
index = index + step
end
index
end
def self.is_previewing?(user_id)
Discourse.redis.get(preview_key(user_id)) == "1"
end
def self.preview_onebox!(user_id)
Discourse.redis.setex(preview_key(user_id), 1.minute, "1")
end
def self.onebox_previewed!(user_id)
Discourse.redis.del(preview_key(user_id))
end
def self.engine(url)
Onebox::Matcher.new(url, {
allowed_iframe_regexes: Onebox::Engine.origins_to_regexes(allowed_iframe_origins)
}).oneboxed
end
def self.recently_failed?(url)
Discourse.cache.read(onebox_failed_cache_key(url)).present?
end
def self.cache_failed!(url)
Discourse.cache.write(onebox_failed_cache_key(url), true, expires_in: 1.hour)
end
private
def self.preview_key(user_id)
"onebox:preview:#{user_id}"
end
def self.blank_onebox
{ preview: "", onebox: "" }
end
def self.onebox_cache_key(url)
"onebox__#{url}"
end
def self.onebox_failed_cache_key(url)
"onebox_failed__#{url}"
end
def self.onebox_raw(url, opts = {})
url = UrlHelper.escape_uri(url).to_s
local_onebox(url, opts) || external_onebox(url)
rescue => e
# no point warning here, just cause we have an issue oneboxing a url
# we can later hunt for failed oneboxes by searching logs if needed
Rails.logger.info("Failed to onebox #{url} #{e} #{e.backtrace}")
# return a blank hash, so rest of the code works
blank_onebox
end
def self.local_onebox(url, opts = {})
return unless route = Discourse.route_for(url)
html =
case route[:controller]
when "uploads" then local_upload_html(url)
when "topics" then local_topic_html(url, route, opts)
when "users" then local_user_html(url, route)
when "list" then local_category_html(url, route)
end
html = html.presence || "<a href='#{URI(url).to_s}'>#{URI(url).to_s}</a>"
{ onebox: html, preview: html }
end
def self.local_upload_html(url)
additional_controls = \
if SiteSetting.disable_onebox_media_download_controls
"controlslist='nodownload'"
else
""
end
case File.extname(URI(url).path || "")
when VIDEO_REGEX
<<~HTML
<div class="onebox video-onebox">
<video #{additional_controls} width="100%" height="100%" controls="">
<source src='#{url}'>
<a href='#{url}'>#{url}</a>
</video>
</div>
HTML
when AUDIO_REGEX
"<audio #{additional_controls} controls><source src='#{url}'><a href='#{url}'>#{url}</a></audio>"
end
end
def self.local_topic(url, route, opts)
if current_user = User.find_by(id: opts[:user_id])
if current_category = Category.find_by(id: opts[:category_id])
return unless Guardian.new(current_user).can_see_category?(current_category)
end
if current_topic = Topic.find_by(id: opts[:topic_id])
return unless Guardian.new(current_user).can_see_topic?(current_topic)
end
end
return unless topic = Topic.find_by(id: route[:id] || route[:topic_id])
return if topic.private_message?
if current_category.blank? || current_category.id != topic.category_id
return unless Guardian.new.can_see_topic?(topic)
end
topic
end
def self.local_topic_html(url, route, opts)
return unless topic = local_topic(url, route, opts)
post_number = route[:post_number].to_i
post = post_number > 1 ?
topic.posts.where(post_number: post_number).first :
topic.ordered_posts.first
return if !post || post.hidden || !allowed_post_types.include?(post.post_type)
if post_number > 1 && opts[:topic_id] == topic.id
excerpt = post.excerpt(SiteSetting.post_onebox_maxlength)
excerpt.gsub!(/[\r\n]+/, " ")
excerpt.gsub!("[/quote]", "[quote]") # don't break my quote
quote = "[quote=\"#{post.user.username}, topic:#{topic.id}, post:#{post.post_number}\"]\n#{excerpt}\n[/quote]"
PrettyText.cook(quote)
else
args = {
topic_id: topic.id,
post_number: post.post_number,
avatar: PrettyText.avatar_img(post.user.avatar_template_url, "tiny"),
original_url: url,
title: PrettyText.unescape_emoji(CGI::escapeHTML(topic.title)),
category_html: CategoryBadge.html_for(topic.category),
quote: PrettyText.unescape_emoji(post.excerpt(SiteSetting.post_onebox_maxlength)),
}
template = template("discourse_topic_onebox")
Mustache.render(template, args)
end
end
def self.local_user_html(url, route)
username = route[:username] || ""
if user = User.find_by(username_lower: username.downcase)
name = user.name if SiteSetting.enable_names
args = {
user_id: user.id,
username: user.username,
avatar: PrettyText.avatar_img(user.avatar_template, "extra_large"),
name: name,
bio: user.user_profile.bio_excerpt(230),
location: Onebox::Helpers.sanitize(user.user_profile.location),
joined: I18n.t('joined'),
created_at: user.created_at.strftime(I18n.t('datetime_formats.formats.date_only')),
website: user.user_profile.website,
website_name: UserSerializer.new(user).website_name,
original_url: url
}
Mustache.render(template("discourse_user_onebox"), args)
else
nil
end
end
def self.local_category_html(url, route)
return unless route[:category_slug_path_with_id]
category = Category.find_by_slug_path_with_id(route[:category_slug_path_with_id])
if Guardian.new.can_see_category?(category)
args = {
url: category.url,
name: category.name,
color: category.color,
logo_url: category.uploaded_logo&.url,
description: category.description,
has_subcategories: category.subcategories.present?,
subcategories: category.subcategories.collect { |sc| { name: sc.name, color: sc.color, url: sc.url } }
}
Mustache.render(template("discourse_category_onebox"), args)
end
end
def self.blocked_domains
SiteSetting.blocked_onebox_domains.split("|")
end
def self.preserve_fragment_url_hosts
@preserve_fragment_url_hosts ||= ['http://github.com']
end
def self.allowed_iframe_origins
allowed = SiteSetting.allowed_onebox_iframes.split("|")
if allowed.include?("*")
allowed = Onebox::Engine.all_iframe_origins
end
allowed += SiteSetting.allowed_iframes.split("|")
end
def self.external_onebox(url, available_strategies = nil)
Discourse.cache.fetch(onebox_cache_key(url), expires_in: 1.day) do
uri = URI(url)
available_strategies ||= Oneboxer.ordered_strategies(uri.hostname)
strategy = available_strategies.shift
fd = FinalDestination.new(url, get_final_destination_options(url, strategy))
uri = fd.resolve
if fd.status != :resolved
args = { link: url }
if fd.status == :invalid_address
args[:error_message] = I18n.t("errors.onebox.invalid_address", hostname: fd.hostname)
elsif (fd.status_code || uri.nil?) && available_strategies.present?
# Try a different oneboxing strategy, if we have any options left:
return external_onebox(url, available_strategies)
elsif fd.status_code
args[:error_message] = I18n.t("errors.onebox.error_response", status_code: fd.status_code)
end
error_box = blank_onebox
error_box[:preview] = preview_error_onebox(args)
return error_box
end
return blank_onebox if uri.blank? || blocked_domains.any? { |hostname| uri.hostname.match?(hostname) }
onebox_options = {
max_width: 695,
sanitize_config: Onebox::DiscourseOneboxSanitizeConfig::Config::DISCOURSE_ONEBOX,
allowed_iframe_origins: allowed_iframe_origins,
hostname: GlobalSetting.hostname,
facebook_app_access_token: SiteSetting.facebook_app_access_token,
disable_media_download_controls: SiteSetting.disable_onebox_media_download_controls,
body_cacher: self,
content_type: fd.content_type
}
onebox_options[:cookie] = fd.cookie if fd.cookie
user_agent_override = SiteSetting.cache_onebox_user_agent if Oneboxer.cache_response_body?(url) && SiteSetting.cache_onebox_user_agent.present?
onebox_options[:user_agent] = user_agent_override if user_agent_override
r = Onebox.preview(uri.to_s, onebox_options)
result = {
onebox: WordWatcher.censor(r.to_s),
preview: WordWatcher.censor(r&.placeholder_html.to_s)
}
# NOTE: Call r.errors after calling placeholder_html
if r.errors.any?
error_keys = r.errors.keys
skip_if_only_error = [:image]
unless error_keys.length == 1 && skip_if_only_error.include?(error_keys.first)
missing_attributes = error_keys.map(&:to_s).sort.join(I18n.t("word_connector.comma"))
error_message = I18n.t("errors.onebox.missing_data", missing_attributes: missing_attributes, count: error_keys.size)
args = r.verified_data.merge(error_message: error_message)
if result[:preview].blank?
result[:preview] = preview_error_onebox(args)
else
doc = Nokogiri::HTML5::fragment(result[:preview])
aside = doc.at('aside')
if aside
# Add an error message to the preview that was returned
error_fragment = preview_error_onebox_fragment(args)
aside.add_child(error_fragment)
result[:preview] = doc.to_html
end
end
end
end
Oneboxer.cache_preferred_strategy(uri.hostname, strategy)
result
end
end
def self.preview_error_onebox(args, is_fragment = false)
args[:title] ||= args[:link] if args[:link]
args[:error_message] = PrettyText.unescape_emoji(args[:error_message]) if args[:error_message]
template_name = is_fragment ? "preview_error_fragment_onebox" : "preview_error_onebox"
Mustache.render(template(template_name), args)
end
def self.preview_error_onebox_fragment(args)
preview_error_onebox(args, true)
end
def self.template(template_name)
@template_cache ||= {}
@template_cache[template_name] ||= begin
full_path = "#{Rails.root}/lib/onebox/templates/#{template_name}.mustache"
File.read(full_path)
end
end
def self.ordered_strategies(hostname)
all = strategies.keys
preferred = Oneboxer.preferred_strategy(hostname)
all.insert(0, all.delete(preferred)) if all.include?(preferred)
all
end
def self.strategies
{
default: {}, # don't override anything by default
force_get_and_ua: {
force_get_host: true,
force_custom_user_agent_host: true,
},
}
end
def self.cache_preferred_strategy(hostname, strategy)
return if strategy == :default
key = redis_oneboxer_strategy_key(hostname)
Discourse.redis.without_namespace.setex(key, 2.weeks.to_i, strategy.to_s)
end
def self.clear_preferred_strategy!(hostname)
key = redis_oneboxer_strategy_key(hostname)
Discourse.redis.without_namespace.del(key)
end
def self.preferred_strategy(hostname)
key = redis_oneboxer_strategy_key(hostname)
Discourse.redis.without_namespace.get(key)&.to_sym
end
def self.redis_oneboxer_strategy_key(hostname)
"ONEBOXER_STRATEGY_#{hostname}"
end
def self.get_final_destination_options(url, strategy = nil)
fd_options = {
ignore_redirects: ignore_redirects,
ignore_hostnames: blocked_domains,
force_get_hosts: force_get_hosts,
force_custom_user_agent_hosts: force_custom_user_agent_hosts,
preserve_fragment_url_hosts: preserve_fragment_url_hosts,
timeout: 5
}
uri = URI(url)
if strategy.blank?
strategy = Oneboxer.ordered_strategies(uri.hostname).shift
end
if strategy && Oneboxer.strategies[strategy][:force_get_host]
fd_options[:force_get_hosts] = ["https://#{uri.hostname}"]
end
if strategy && Oneboxer.strategies[strategy][:force_custom_user_agent_host]
fd_options[:force_custom_user_agent_hosts] = ["https://#{uri.hostname}"]
end
user_agent_override = SiteSetting.cache_onebox_user_agent if Oneboxer.cache_response_body?(url) && SiteSetting.cache_onebox_user_agent.present?
fd_options[:default_user_agent] = user_agent_override if user_agent_override
fd_options
end
end