discourse/lib/site_setting_extension.rb

# frozen_string_literal: true

module SiteSettingExtension
  include SiteSettings::DeprecatedSettings
  include HasSanitizableFields

  # support default_locale being set via global settings
  # this also adds support for testing the extension and global settings
  # for site locale
  def self.extended(klass)
    if GlobalSetting.respond_to?(:default_locale) && GlobalSetting.default_locale.present?
      # protected
      klass.send :setup_shadowed_methods, :default_locale, GlobalSetting.default_locale
    end
  end

  # we need a default here to support defaults per locale
  def default_locale=(val)
    val = val.to_s
    raise Discourse::InvalidParameters.new(:value) unless LocaleSiteSetting.valid_value?(val)
    if val != self.default_locale
      add_override!(:default_locale, val)
      refresh!
      Discourse.request_refresh!
    end
  end

  def default_locale?
    true
  end

  # set up some sort of default so we can look stuff up
  def default_locale
    # note optimised cause this is called a lot so avoiding .presence which
    # adds 2 method calls
    locale = current[:default_locale]
    if locale && !locale.blank?
      locale
    else
      SiteSettings::DefaultsProvider::DEFAULT_LOCALE
    end
  end

  def has_setting?(v)
    defaults.has_setting?(v)
  end

  def supported_types
    SiteSettings::TypeSupervisor.supported_types
  end

  def types
    SiteSettings::TypeSupervisor.types
  end

  def listen_for_changes=(val)
    @listen_for_changes = val
  end

  def provider=(val)
    @provider = val
    refresh!
  end

  def provider
    @provider ||= SiteSettings::DbProvider.new(SiteSetting)
  end

  def mutex
    @mutex ||= Mutex.new
  end

  def current
    @containers ||= {}
    @containers[provider.current_site] ||= {}
  end

  def defaults
    @defaults ||= SiteSettings::DefaultsProvider.new(self)
  end

  def type_supervisor
    @type_supervisor ||= SiteSettings::TypeSupervisor.new(defaults)
  end

  def categories
    @categories ||= {}
  end

  def shadowed_settings
    @shadowed_settings ||= []
  end

  def hidden_settings
    @hidden_settings ||= []
  end

  def refresh_settings
    @refresh_settings ||= [:default_locale]
  end

  def client_settings
    @client_settings ||= [:default_locale]
  end

  def previews
    @previews ||= {}
  end

  def secret_settings
    @secret_settings ||= []
  end

  def plugins
    @plugins ||= {}
  end

  def setting(name_arg, default = nil, opts = {})
    name = name_arg.to_sym

    if name == :default_locale
      raise Discourse::InvalidParameters.new(
              "Other settings depend on default locale, you can not configure it like this",
            )
    end

    shadowed_val = nil

    mutex.synchronize do
      defaults.load_setting(name, default, opts.delete(:locale_default))

      categories[name] = opts[:category] || :uncategorized

      hidden_settings << name if opts[:hidden]

      if GlobalSetting.respond_to?(name)
        val = GlobalSetting.public_send(name)

        unless val.nil? || (val == "")
          shadowed_val = val
          hidden_settings << name
          shadowed_settings << name
        end
      end

      refresh_settings << name if opts[:refresh]

      client_settings << name.to_sym if opts[:client]

      previews[name] = opts[:preview] if opts[:preview]

      secret_settings << name if opts[:secret]

      plugins[name] = opts[:plugin] if opts[:plugin]

      type_supervisor.load_setting(
        name,
        opts.extract!(*SiteSettings::TypeSupervisor::CONSUMED_OPTS),
      )

      if !shadowed_val.nil?
        setup_shadowed_methods(name, shadowed_val)
      else
        setup_methods(name)
      end
    end
  end

  def settings_hash
    result = {}
    deprecated_settings = Set.new

    SiteSettings::DeprecatedSettings::SETTINGS.each { |s| deprecated_settings << s[0] }

    defaults.all.keys.each do |s|
      result[s] = if deprecated_settings.include?(s.to_s)
        public_send(s, warn: false).to_s
      else
        public_send(s).to_s
      end
    end

    result
  end

  def client_settings_json
    Discourse
      .cache
      .fetch(SiteSettingExtension.client_settings_cache_key, expires_in: 30.minutes) do
        client_settings_json_uncached
      end
  end

  def client_settings_json_uncached
    MultiJson.dump(
      Hash[
        *@client_settings
          .map do |name|
            value = self.public_send(name)
            type = type_supervisor.get_type(name)
            value = value.to_s if type == :upload
            value = value.map(&:to_s).join("|") if type == :uploaded_image_list

            [name, value]
          end
          .flatten
      ],
    )
  end

  # Retrieve all settings
  def all_settings(include_hidden: false)
    locale_setting_hash = {
      setting: "default_locale",
      default: SiteSettings::DefaultsProvider::DEFAULT_LOCALE,
      category: "required",
      description: description("default_locale"),
      type: SiteSetting.types[SiteSetting.types[:enum]],
      preview: nil,
      value: self.default_locale,
      valid_values: LocaleSiteSetting.values,
      translate_names: LocaleSiteSetting.translate_names?,
    }

    defaults
      .all(default_locale)
      .reject { |setting_name, _| !include_hidden && hidden_settings.include?(setting_name) }
      .map do |s, v|
        type_hash = type_supervisor.type_hash(s)
        default = defaults.get(s, default_locale).to_s

        value = public_send(s)
        value = value.map(&:to_s).join("|") if type_hash[:type].to_s == "uploaded_image_list"

        if type_hash[:type].to_s == "upload" && default.to_i < Upload::SEEDED_ID_THRESHOLD
          default = default_uploads[default.to_i]
        end

        opts = {
          setting: s,
          description: description(s),
          default: default,
          value: value.to_s,
          category: categories[s],
          preview: previews[s],
          secret: secret_settings.include?(s),
          placeholder: placeholder(s),
        }.merge!(type_hash)

        opts[:plugin] = plugins[s] if plugins[s]

        opts
      end
      .unshift(locale_setting_hash)
  end

  def description(setting)
    I18n.t("site_settings.#{setting}", base_path: Discourse.base_path)
  end

  def placeholder(setting)
    if !I18n.t("site_settings.placeholder.#{setting}", default: "").empty?
      I18n.t("site_settings.placeholder.#{setting}")
    elsif SiteIconManager.respond_to?("#{setting}_url")
      SiteIconManager.public_send("#{setting}_url")
    end
  end

  def self.client_settings_cache_key
    # NOTE: we use the git version in the key to ensure
    # that we don't end up caching the incorrect version
    # in cases where we are cycling unicorns
    "client_settings_json_#{Discourse.git_version}"
  end

  # refresh all the site settings
  def refresh!
    mutex.synchronize do
      ensure_listen_for_changes

      new_hash =
        Hash[
          *(
            defaults
              .db_all
              .map do |s|
                [s.name.to_sym, type_supervisor.to_rb_value(s.name, s.value, s.data_type)]
              end
              .to_a
              .flatten
          )
        ]

      defaults_view = defaults.all(new_hash[:default_locale])

      # add locale default and defaults based on default_locale, cause they are cached
      new_hash = defaults_view.merge!(new_hash)

      # add shadowed
      shadowed_settings.each { |ss| new_hash[ss] = GlobalSetting.public_send(ss) }

      changes, deletions = diff_hash(new_hash, current)

      changes.each { |name, val| current[name] = val }
      deletions.each { |name, _| current[name] = defaults_view[name] }
      uploads.clear

      clear_cache!
    end
  end

  def ensure_listen_for_changes
    return if @listen_for_changes == false

    unless @subscribed
      MessageBus.subscribe("/site_settings") do |message|
        process_message(message) if message.data["process"] != process_id
      end

      @subscribed = true
    end
  end

  def process_message(message)
    begin
      MessageBus.on_connect.call(message.site_id)
      refresh!
    ensure
      MessageBus.on_disconnect.call(message.site_id)
    end
  end

  def process_id
    @process_id ||= SecureRandom.uuid
  end

  def after_fork
    @process_id = nil
    ensure_listen_for_changes
  end

  def remove_override!(name)
    old_val = current[name]
    provider.destroy(name)
    current[name] = defaults.get(name, default_locale)

    return if current[name] == old_val

    clear_uploads_cache(name)
    clear_cache!
    if old_val != current[name]
      DiscourseEvent.trigger(:site_setting_changed, name, old_val, current[name])
    end
  end

  def add_override!(name, val)
    old_val = current[name]
    val, type = type_supervisor.to_db_value(name, val)

    sanitize_override = val.is_a?(String) && client_settings.include?(name)

    sanitized_val = sanitize_override ? sanitize_field(val) : val
    provider.save(name, sanitized_val, type)
    current[name] = type_supervisor.to_rb_value(name, sanitized_val)

    return if current[name] == old_val

    clear_uploads_cache(name)
    notify_clients!(name) if client_settings.include? name
    clear_cache!
    if old_val != current[name]
      DiscourseEvent.trigger(:site_setting_changed, name, old_val, current[name])
    end
  end

  def notify_changed!
    MessageBus.publish("/site_settings", process: process_id)
  end

  def notify_clients!(name)
    MessageBus.publish("/client_settings", name: name, value: self.public_send(name))
  end

  def requires_refresh?(name)
    refresh_settings.include?(name.to_sym)
  end

  HOSTNAME_SETTINGS ||= %w[
    disabled_image_download_domains
    blocked_onebox_domains
    exclude_rel_nofollow_domains
    blocked_email_domains
    allowed_email_domains
    allowed_spam_host_domains
  ]

  def filter_value(name, value)
    if HOSTNAME_SETTINGS.include?(name)
      value
        .split("|")
        .map do |url|
          url.strip!
          get_hostname(url)
        end
        .compact
        .uniq
        .join("|")
    else
      value
    end
  end

  def set(name, value, options = nil)
    if has_setting?(name)
      value = filter_value(name, value)
      if options
        self.public_send("#{name}=", value, options)
      else
        self.public_send("#{name}=", value)
      end
      Discourse.request_refresh! if requires_refresh?(name)
    else
      raise Discourse::InvalidParameters.new(
              "Either no setting named '#{name}' exists or value provided is invalid",
            )
    end
  end

  def set_and_log(name, value, user = Discourse.system_user)
    if has_setting?(name)
      prev_value = public_send(name)
      set(name, value)
      value = prev_value = "[FILTERED]" if secret_settings.include?(name.to_sym)
      StaffActionLogger.new(user).log_site_setting_change(name, prev_value, value)
    else
      raise Discourse::InvalidParameters.new("No setting named '#{name}' exists")
    end
  end

  def get(name)
    if has_setting?(name)
      self.public_send(name)
    else
      raise Discourse::InvalidParameters.new("No setting named '#{name}' exists")
    end
  end

  if defined?(Rails::Console)
    # Convenience method for debugging site setting issues
    # Returns a hash with information about a specific setting
    def info(name)
      {
        resolved_value: get(name),
        default_value: defaults[name],
        global_override: GlobalSetting.respond_to?(name) ? GlobalSetting.public_send(name) : nil,
        database_value: provider.find(name)&.value,
        refresh?: refresh_settings.include?(name),
        client?: client_settings.include?(name),
        secret?: secret_settings.include?(name),
      }
    end
  end

  protected

  def clear_cache!
    Discourse.cache.delete(SiteSettingExtension.client_settings_cache_key)
    Site.clear_anon_cache!
  end

  def diff_hash(new_hash, old)
    changes = []
    deletions = []

    new_hash.each do |name, value|
      changes << [name, value] if !old.has_key?(name) || old[name] != value
    end

    old.each { |name, value| deletions << [name, value] unless new_hash.has_key?(name) }

    [changes, deletions]
  end

  def setup_shadowed_methods(name, value)
    clean_name = name.to_s.sub("?", "").to_sym

    define_singleton_method clean_name do
      value
    end

    define_singleton_method "#{clean_name}?" do
      value
    end

    define_singleton_method "#{clean_name}=" do |val|
      if value != val
        Rails.logger.warn(
          "An attempt was to change #{clean_name} SiteSetting to #{val} however it is shadowed so this will be ignored!",
        )
      end
      nil
    end
  end

  def setup_methods(name)
    clean_name = name.to_s.sub("?", "").to_sym

    if type_supervisor.get_type(name) == :uploaded_image_list
      define_singleton_method clean_name do
        uploads_list = uploads[name]
        return uploads_list if uploads_list

        if (value = current[name]).nil?
          refresh!
          value = current[name]
        end

        return [] if value.empty?

        value = value.split("|").map(&:to_i)
        uploads_list = Upload.where(id: value).to_a
        uploads[name] = uploads_list if uploads_list
      end
    elsif type_supervisor.get_type(name) == :upload
      define_singleton_method clean_name do
        upload = uploads[name]
        return upload if upload

        if (value = current[name]).nil?
          refresh!
          value = current[name]
        end

        value = value.to_i

        if value != Upload::SEEDED_ID_THRESHOLD
          upload = Upload.find_by(id: value)
          uploads[name] = upload if upload
        end
      end
    else
      define_singleton_method clean_name do
        if (c = current[name]).nil?
          refresh!
          current[name]
        else
          c
        end
      end
    end

    # Any group_list setting, e.g. personal_message_enabled_groups, will have
    # a getter defined with _map on the end, e.g. personal_message_enabled_groups_map,
    # to avoid having to manually split and convert to integer for these settings.
    if type_supervisor.get_type(name) == :group_list
      define_singleton_method("#{clean_name}_map") do
        self.public_send(clean_name).to_s.split("|").map(&:to_i)
      end
    end

    define_singleton_method "#{clean_name}?" do
      self.public_send clean_name
    end

    define_singleton_method "#{clean_name}=" do |val|
      add_override!(name, val)
    end
  end

  def get_hostname(url)
    host =
      begin
        URI.parse(url)&.host
      rescue URI::Error
        nil
      end

    host ||=
      begin
        URI.parse("http://#{url}")&.host
      rescue URI::Error
        nil
      end

    host.presence || url
  end

  private

  def default_uploads
    @default_uploads ||= {}

    @default_uploads[provider.current_site] ||= begin
      Upload.where("id < ?", Upload::SEEDED_ID_THRESHOLD).pluck(:id, :url).to_h
    end
  end

  def uploads
    @uploads ||= {}
    @uploads[provider.current_site] ||= {}
  end

  def clear_uploads_cache(name)
    if (
         type_supervisor.get_type(name) == :upload ||
           type_supervisor.get_type(name) == :uploaded_image_list
       ) && uploads.has_key?(name)
      uploads.delete(name)
    end
  end

  def logger
    Rails.logger
  end
end