Add: フレンドサーバー (#61)

* Fix mastodon version

* テーブル作成

* Wip: フレンドサーバーフォローの承認を受信

* Wip: フレンド申請拒否を受信

* Wip: フォローリクエストを受理

* Wip: 相手からのフォロー・アンフォローを受理

* 普通のフォローとフレンドサーバーのフォローを区別するテストを追加

* ドメインブロックによるフォロー拒否

* ドメインブロックしたあと、申請中のフォロリクを取り下げる処理

* スタブに条件を追加

* Wip: 相手からのDelete信号に対応

* DB定義が消えていたので修正

* Wip: ローカル公開投稿をフレンドに送信する処理など

* Wip: 未収載＋誰でもの投稿をフレンドに送る設定

* Wip: ローカル公開をそのまま送信する設定を考慮

* Fix test

* Wip: 他サーバーからのローカル公開投稿の受け入れ

* Wip: Web画面作成

* Fix test

* Wip: ローカル公開を連合TLに流す

* Wip: フレンドサーバーの削除ボタン

* Wip: メール通知や設定のテストなど

* Wip: 翻訳を作成

* Fix: 却下されたあとフォローボタンが表示されない問題

* Wip: 編集できない問題

* 有効にしていないフレンドサーバーをリストで無効表示

app/controllers/admin/domain_blocks_controller.rb

@@ -89,17 +89,17 @@ module Admin
 
     def update_params
       params.require(:domain_block).permit(:severity, :reject_media, :reject_favourite, :reject_reply, :reject_reply_exclude_followers, :reject_send_not_public_searchability, :reject_send_public_unlisted, :reject_send_dissubscribable, :reject_send_media, :reject_send_sensitive, :reject_hashtag,
-                                           :reject_straight_follow, :reject_new_follow, :detect_invalid_subscription, :reject_reports, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous)
+                                           :reject_straight_follow, :reject_new_follow, :reject_friend, :detect_invalid_subscription, :reject_reports, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous)
     end
 
     def resource_params
       params.require(:domain_block).permit(:domain, :severity, :reject_media, :reject_favourite, :reject_reply, :reject_reply_exclude_followers, :reject_send_not_public_searchability, :reject_send_public_unlisted, :reject_send_dissubscribable, :reject_send_media, :reject_send_sensitive, :reject_hashtag,
-                                           :reject_straight_follow, :reject_new_follow, :detect_invalid_subscription, :reject_reports, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous)
+                                           :reject_straight_follow, :reject_new_follow, :reject_friend, :detect_invalid_subscription, :reject_reports, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous)
     end
 
     def form_domain_block_batch_params
       params.require(:form_domain_block_batch).permit(domain_blocks_attributes: [:enabled, :domain, :severity, :reject_media, :reject_favourite, :reject_reply, :reject_reply_exclude_followers, :reject_send_not_public_searchability, :reject_send_public_unlisted, :reject_send_dissubscribable, :reject_send_media,
-                                                                                 :reject_send_sensitive, :reject_hashtag, :reject_straight_follow, :reject_new_follow, :detect_invalid_subscription, :reject_reports, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous])
+                                                                                 :reject_send_sensitive, :reject_hashtag, :reject_straight_follow, :reject_new_follow, :reject_friend, :detect_invalid_subscription, :reject_reports, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous])
     end
 
     def action_from_button

app/controllers/admin/friend_servers_controller.rb

@@ -0,0 +1,89 @@
+# frozen_string_literal: true
+
+module Admin
+  class FriendServersController < BaseController
+    before_action :set_friend, except: [:index, :new, :create]
+    before_action :warn_signatures_not_enabled!, only: [:new, :edit, :create, :follow, :unfollow, :accept, :reject]
+
+    def index
+      authorize :friend_server, :update?
+      @friends = FriendDomain.all
+    end
+
+    def new
+      authorize :friend_server, :update?
+      @friend = FriendDomain.new
+    end
+
+    def edit
+      authorize :friend_server, :update?
+    end
+
+    def create
+      authorize :friend_server, :update?
+
+      @friend = FriendDomain.new(resource_params)
+
+      if @friend.save
+        @friend.follow!
+        redirect_to admin_friend_servers_path
+      else
+        render action: :new
+      end
+    end
+
+    def update
+      authorize :friend_server, :update?
+
+      if @friend.update(resource_params)
+        redirect_to admin_friend_servers_path
+      else
+        render action: :edit
+      end
+    end
+
+    def destroy
+      authorize :friend_server, :update?
+      @friend.destroy
+      redirect_to admin_friend_servers_path
+    end
+
+    def follow
+      authorize :friend_server, :update?
+      @friend.follow!
+      render action: :edit
+    end
+
+    def unfollow
+      authorize :friend_server, :update?
+      @friend.unfollow!
+      render action: :edit
+    end
+
+    def accept
+      authorize :friend_server, :update?
+      @friend.accept!
+      render action: :edit
+    end
+
+    def reject
+      authorize :friend_server, :update?
+      @friend.reject!
+      render action: :edit
+    end
+
+    private
+
+    def set_friend
+      @friend = FriendDomain.find(params[:id])
+    end
+
+    def resource_params
+      params.require(:friend_domain).permit(:domain, :inbox_url, :available, :pseudo_relay, :unlocked, :allow_all_posts)
+    end
+
+    def warn_signatures_not_enabled!
+      flash.now[:error] = I18n.t('admin.relays.signatures_not_enabled') if authorized_fetch_mode?
+    end
+  end
+end

app/controllers/api/v1/admin/domain_blocks_controller.rb

@@ -70,7 +70,7 @@ class Api::V1::Admin::DomainBlocksController < Api::BaseController
 
   def domain_block_params
     params.permit(:severity, :reject_media, :reject_favourite, :reject_reply, :reject_reply_exclude_followers, :reject_reports, :reject_send_not_public_searchability, :reject_send_public_unlisted, :reject_send_dissubscribable, :reject_send_media, :reject_send_sensitive, :reject_hashtag, :reject_straight_follow,
-                  :reject_new_follow, :detect_invalid_subscription, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous)
+                  :reject_new_follow, :reject_friend, :detect_invalid_subscription, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous)
   end
 
   def insert_pagination_headers
@@ -103,6 +103,6 @@ class Api::V1::Admin::DomainBlocksController < Api::BaseController
 
   def resource_params
     params.permit(:domain, :severity, :reject_media, :reject_favourite, :reject_reply, :reject_reply_exclude_followers, :reject_send_not_public_searchability, :reject_send_public_unlisted, :reject_send_dissubscribable, :reject_send_media, :reject_send_sensitive, :reject_hashtag, :reject_straight_follow,
-                  :reject_new_follow, :detect_invalid_subscription, :reject_reports, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous)
+                  :reject_new_follow, :reject_friend, :detect_invalid_subscription, :reject_reports, :private_comment, :public_comment, :obfuscate, :hidden, :hidden_anonymous)
   end
 end

app/lib/activitypub/activity/accept.rb

@@ -3,6 +3,7 @@
 class ActivityPub::Activity::Accept < ActivityPub::Activity
   def perform
     return accept_follow_for_relay if relay_follow?
+    return accept_follow_for_friend if friend_follow?
     return accept_follow!(follow_request_from_object) unless follow_request_from_object.nil?
 
     case @object['type']
@@ -43,6 +44,18 @@ class ActivityPub::Activity::Accept < ActivityPub::Activity
     relay.present?
   end
 
+  def accept_follow_for_friend
+    friend.update!(active_state: :accepted)
+  end
+
+  def friend
+    @friend ||= FriendDomain.find_by(domain: @account.domain, active_follow_activity_id: object_uri, active_state: [:pending, :accepted]) if @account.domain.present?
+  end
+
+  def friend_follow?
+    friend.present?
+  end
+
   def target_uri
     @target_uri ||= value_or_id(@object['actor'])
   end

app/lib/activitypub/activity/create.rb

@@ -447,7 +447,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
 
   def related_to_local_activity?
     fetch? || followed_by_local_accounts? || requested_through_relay? ||
-      responds_to_followed_account? || addresses_local_accounts? || quote_local?
+      responds_to_followed_account? || addresses_local_accounts? || quote_local? || free_friend_domain?
   end
 
   def responds_to_followed_account?
@@ -502,6 +502,10 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     end
   end
 
+  def free_friend_domain?
+    FriendDomain.free_receivings.exists?(domain: @account.domain)
+  end
+
   def quote
     @quote ||= @object['quote'] || @object['quoteUrl'] || @object['quoteURL'] || @object['_misskey_quote']
   end

app/lib/activitypub/activity/delete.rb

@@ -4,6 +4,8 @@ class ActivityPub::Activity::Delete < ActivityPub::Activity
   def perform
     if @account.uri == object_uri
       delete_person
+    elsif object_uri == ActivityPub::TagManager::COLLECTIONS[:public]
+      delete_friend
     else
       delete_note
     end
@@ -42,6 +44,11 @@ class ActivityPub::Activity::Delete < ActivityPub::Activity
     end
   end
 
+  def delete_friend
+    friend = FriendDomain.find_by(domain: @account.domain)
+    friend&.destroy
+  end
+
   def forwarder
     @forwarder ||= ActivityPub::Forwarder.new(@account, @json, @status)
   end

app/lib/activitypub/activity/follow.rb

@@ -4,6 +4,8 @@ class ActivityPub::Activity::Follow < ActivityPub::Activity
   include Payloadable
 
   def perform
+    return request_follow_for_friend if friend_follow?
+
     target_account = account_from_uri(object_uri)
 
     return if target_account.nil? || !target_account.local? || delete_arrived_first?(@json['id'])
@@ -43,6 +45,36 @@ class ActivityPub::Activity::Follow < ActivityPub::Activity
     ActivityPub::DeliveryWorker.perform_async(json, target_account.id, @account.inbox_url)
   end
 
+  def request_follow_for_friend
+    already_accepted = false
+
+    if friend.present?
+      already_accepted = friend.they_are_accepted?
+      friend.update!(passive_state: :pending, passive_follow_activity_id: @json['id'])
+    else
+      @friend = FriendDomain.create!(domain: @account.domain, passive_state: :pending, passive_follow_activity_id: @json['id'])
+    end
+
+    if already_accepted || friend.unlocked || Setting.unlocked_friend
+      friend.accept!
+    else
+      # Notify for admin even if unlocked
+      notify_staff_about_pending_friend_server!
+    end
+  end
+
+  def friend
+    @friend ||= FriendDomain.find_by(domain: @account.domain) if @account.domain.present?
+  end
+
+  def friend_follow?
+    @json['object'] == ActivityPub::TagManager::COLLECTIONS[:public] && !block_friend?
+  end
+
+  def block_friend?
+    @block_friend ||= DomainBlock.reject_friend?(@account.domain) || DomainBlock.blocked?(@account.domain)
+  end
+
   def block_straight_follow?
     @block_straight_follow ||= DomainBlock.reject_straight_follow?(@account.domain)
   end
@@ -73,4 +105,12 @@ class ActivityPub::Activity::Follow < ActivityPub::Activity
   def instance_info
     @instance_info ||= InstanceInfo.find_by(domain: @account.domain)
   end
+
+  def notify_staff_about_pending_friend_server!
+    User.those_who_can(:manage_federation).includes(:account).find_each do |u|
+      next unless u.allows_pending_friend_server_emails?
+
+      AdminMailer.with(recipient: u.account).new_pending_friend_server(friend).deliver_later
+    end
+  end
 end

app/lib/activitypub/activity/reject.rb

@@ -3,6 +3,7 @@
 class ActivityPub::Activity::Reject < ActivityPub::Activity
   def perform
     return reject_follow_for_relay if relay_follow?
+    return reject_follow_for_friend if friend_follow?
     return follow_request_from_object.reject! unless follow_request_from_object.nil?
     return UnfollowService.new.call(follow_from_object.account, @account) unless follow_from_object.nil?
 
@@ -37,6 +38,18 @@ class ActivityPub::Activity::Reject < ActivityPub::Activity
     relay.present?
   end
 
+  def reject_follow_for_friend
+    friend.update!(active_state: :rejected)
+  end
+
+  def friend
+    @friend ||= FriendDomain.find_by(domain: @account.domain, active_follow_activity_id: object_uri, active_state: [:pending, :accepted]) if @account.domain.present?
+  end
+
+  def friend_follow?
+    friend.present?
+  end
+
   def target_uri
     @target_uri ||= value_or_id(@object['actor'])
   end

app/lib/activitypub/activity/undo.rb

@@ -87,6 +87,8 @@ class ActivityPub::Activity::Undo < ActivityPub::Activity
   end
 
   def undo_follow
+    return remove_follow_from_friend if friend_follow?
+
     target_account = account_from_uri(target_uri)
 
     return if target_account.nil? || !target_account.local?
@@ -100,6 +102,18 @@ class ActivityPub::Activity::Undo < ActivityPub::Activity
     end
   end
 
+  def remove_follow_from_friend
+    friend.update!(passive_state: :idle, passive_follow_activity_id: nil)
+  end
+
+  def friend
+    @friend ||= FriendDomain.find_by(domain: @account.domain) if @account.domain.present? && @object['object'] == ActivityPub::TagManager::COLLECTIONS[:public]
+  end
+
+  def friend_follow?
+    friend.present?
+  end
+
   def undo_like_original
     status = status_from_uri(target_uri)
 

app/lib/activitypub/parser/status_parser.rb

@@ -76,6 +76,8 @@ class ActivityPub::Parser::StatusParser
   def visibility
     if audience_to.any? { |to| ActivityPub::TagManager.instance.public_collection?(to) }
       :public
+    elsif audience_to.include?('LocalPublic')
+      :public_unlisted
     elsif audience_cc.any? { |cc| ActivityPub::TagManager.instance.public_collection?(cc) }
       :unlisted
     elsif audience_to.include?('as:LoginOnly') || audience_to.include?('LoginUser')
@@ -198,6 +200,8 @@ class ActivityPub::Parser::StatusParser
       :public
     elsif audience_searchable_by.include?('as:Limited')
       :limited
+    elsif audience_searchable_by.include?('LocalPublic')
+      :public_unlisted
     elsif audience_searchable_by.include?(@account.followers_url)
       :private
     else

app/lib/activitypub/tag_manager.rb

@@ -126,6 +126,12 @@ class ActivityPub::TagManager
     end
   end
 
+  def to_for_friend(status)
+    to = to(status)
+    to << 'LocalPublic' if status.public_unlisted_visibility?
+    to
+  end
+
   # Secondary audience of a status
   # Public statuses go out to followers as well
   # Unlisted statuses go to the public as well
@@ -147,7 +153,7 @@ class ActivityPub::TagManager
   end
 
   def cc_for_misskey(status)
-    if (status.account.user&.setting_reject_unlisted_subscription && status.visibility == 'unlisted') || (status.account.user&.setting_reject_public_unlisted_subscription && status.visibility == 'public_unlisted')
+    if (status.account.user&.setting_reject_unlisted_subscription && status.unlisted_visibility?) || (status.account.user&.setting_reject_public_unlisted_subscription && status.public_unlisted_visibility?)
       cc = cc_private_visibility(status)
       cc << uri_for(status.reblog.account) if status.reblog?
       return cc
@@ -251,6 +257,12 @@ class ActivityPub::TagManager
     searchable_by.concat(mentions_uris(status)).compact
   end
 
+  def searchable_by_for_friend(status)
+    searchable = searchable_by(status)
+    searchable << 'LocalPublic' if status.compute_searchability_local == 'public_unlisted'
+    searchable
+  end
+
   def account_searchable_by(account)
     case account.compute_searchability_activitypub
     when 'public'

app/lib/status_reach_finder.rb

@@ -21,6 +21,10 @@ class StatusReachFinder
     end
   end
 
+  def inboxes_for_friend
+    (reached_account_inboxes_for_friend + followers_inboxes_for_friend + friend_inboxes).uniq
+  end
+
   private
 
   def reached_account_inboxes
@@ -32,7 +36,7 @@ class StatusReachFinder
     elsif @status.limited_visibility?
       Account.where(id: mentioned_account_ids).where.not(domain: banned_domains).inboxes
     else
-      Account.where(id: reached_account_ids).where.not(domain: banned_domains).inboxes
+      Account.where(id: reached_account_ids).where.not(domain: banned_domains + friend_domains).inboxes
     end
   end
 
@@ -42,7 +46,17 @@ class StatusReachFinder
     elsif @status.limited_visibility?
       Account.where(id: mentioned_account_ids).where(domain: banned_domains_for_misskey).inboxes
     else
-      Account.where(id: reached_account_ids).where(domain: banned_domains_for_misskey).inboxes
+      Account.where(id: reached_account_ids).where(domain: banned_domains_for_misskey - friend_domains).inboxes
+    end
+  end
+
+  def reached_account_inboxes_for_friend
+    if @status.reblog?
+      []
+    elsif @status.limited_visibility?
+      Account.where(id: mentioned_account_ids).where.not(domain: banned_domains).inboxes
+    else
+      Account.where(id: reached_account_ids, domain: friend_domains).where.not(domain: banned_domains - friend_domains).inboxes
     end
   end
 
@@ -95,21 +109,31 @@ class StatusReachFinder
 
   def followers_inboxes
     if @status.in_reply_to_local_account? && distributable?
-      @status.account.followers.or(@status.thread.account.followers.not_domain_blocked_by_account(@status.account)).where.not(domain: banned_domains).inboxes
+      @status.account.followers.or(@status.thread.account.followers.not_domain_blocked_by_account(@status.account)).where.not(domain: banned_domains + friend_domains).inboxes
     elsif @status.direct_visibility? || @status.limited_visibility?
       []
     else
-      @status.account.followers.where.not(domain: banned_domains).inboxes
+      @status.account.followers.where.not(domain: banned_domains + friend_domains).inboxes
     end
   end
 
   def followers_inboxes_for_misskey
     if @status.in_reply_to_local_account? && distributable?
-      @status.account.followers.or(@status.thread.account.followers.not_domain_blocked_by_account(@status.account)).where(domain: banned_domains_for_misskey).inboxes
+      @status.account.followers.or(@status.thread.account.followers.not_domain_blocked_by_account(@status.account)).where(domain: banned_domains_for_misskey - friend_domains).inboxes
     elsif @status.direct_visibility? || @status.limited_visibility?
       []
     else
-      @status.account.followers.where(domain: banned_domains_for_misskey).inboxes
+      @status.account.followers.where(domain: banned_domains_for_misskey - friend_domains).inboxes
+    end
+  end
+
+  def followers_inboxes_for_friend
+    if @status.in_reply_to_local_account? && distributable?
+      @status.account.followers.or(@status.thread.account.followers.not_domain_blocked_by_account(@status.account)).where(domain: friend_domains).inboxes
+    elsif @status.direct_visibility? || @status.limited_visibility?
+      []
+    else
+      @status.account.followers.where(domain: friend_domains).inboxes
     end
   end
 
@@ -121,6 +145,14 @@ class StatusReachFinder
     end
   end
 
+  def friend_inboxes
+    if @status.public_visibility? || @status.public_unlisted_visibility? || (@status.unlisted_visibility? && (@status.public_searchability? || @status.public_unlisted_searchability?))
+      DeliveryFailureTracker.without_unavailable(FriendDomain.distributables.pluck(:inbox_url))
+    else
+      []
+    end
+  end
+
   def distributable?
     @status.public_visibility? || @status.unlisted_visibility? || @status.public_unlisted_visibility?
   end
@@ -129,6 +161,13 @@ class StatusReachFinder
     @options[:unsafe]
   end
 
+  def friend_domains
+    return @friend_domains if defined?(@friend_domains)
+
+    @friend_domains = FriendDomain.deliver_locals.pluck(:domain)
+    @friend_domains -= UnavailableDomain.where(domain: @friend_domains).pluck(:domain)
+  end
+
   def banned_domains
     return @banned_domains if @banned_domains
 

app/mailers/admin_mailer.rb

@@ -35,6 +35,14 @@ class AdminMailer < ApplicationMailer
     end
   end
 
+  def new_pending_friend_server(friend_server)
+    @friend = friend_server
+
+    locale_for_account(@me) do
+      mail subject: default_i18n_subject(instance: @instance, domain: @friend.domain)
+    end
+  end
+
   def new_trends(links, tags, statuses)
     @links                  = links
     @tags                   = tags

app/models/concerns/has_user_settings.rb

@@ -263,6 +263,10 @@ module HasUserSettings
     settings['notification_emails.pending_account']
   end
 
+  def allows_pending_friend_server_emails?
+    settings['notification_emails.pending_friend_server']
+  end
+
   def allows_appeal_emails?
     settings['notification_emails.appeal']
   end

app/models/domain_block.rb

@@ -28,6 +28,7 @@
 #  hidden_anonymous                     :boolean          default(FALSE), not null
 #  detect_invalid_subscription          :boolean          default(FALSE), not null
 #  reject_reply_exclude_followers       :boolean          default(FALSE), not null
+#  reject_friend                        :boolean          default(FALSE), not null
 #
 
 class DomainBlock < ApplicationRecord
@@ -44,7 +45,16 @@ class DomainBlock < ApplicationRecord
 
   scope :matches_domain, ->(value) { where(arel_table[:domain].matches("%#{value}%")) }
   scope :with_user_facing_limitations, -> { where(hidden: false) }
-  scope :with_limitations, -> { where(severity: [:silence, :suspend]).or(where(reject_media: true)).or(where(reject_favourite: true)).or(where(reject_reply: true)).or(where(reject_reply_exclude_followers: true)).or(where(reject_new_follow: true)).or(where(reject_straight_follow: true)) }
+  scope :with_limitations, lambda {
+    where(severity: [:silence, :suspend])
+      .or(where(reject_media: true))
+      .or(where(reject_favourite: true))
+      .or(where(reject_reply: true))
+      .or(where(reject_reply_exclude_followers: true))
+      .or(where(reject_new_follow: true))
+      .or(where(reject_straight_follow: true))
+      .or(where(reject_friend: true))
+  }
   scope :by_severity, -> { order(Arel.sql('(CASE severity WHEN 0 THEN 1 WHEN 1 THEN 2 WHEN 2 THEN 0 END), domain')) }
 
   def to_log_human_identifier
@@ -68,6 +78,7 @@ class DomainBlock < ApplicationRecord
        reject_hashtag? ? :reject_hashtag : nil,
        reject_straight_follow? ? :reject_straight_follow : nil,
        reject_new_follow? ? :reject_new_follow : nil,
+       reject_friend? ? :reject_friend : nil,
        detect_invalid_subscription? ? :detect_invalid_subscription : nil,
        reject_reports? ? :reject_reports : nil].reject { |policy| policy == :noop || policy.nil? }
     end
@@ -110,6 +121,10 @@ class DomainBlock < ApplicationRecord
       !!rule_for(domain)&.reject_new_follow?
     end
 
+    def reject_friend?(domain)
+      !!rule_for(domain)&.reject_friend?
+    end
+
     def detect_invalid_subscription?(domain)
       !!rule_for(domain)&.detect_invalid_subscription?
     end

app/models/form/admin_settings.rb

@@ -48,6 +48,7 @@ class Form::AdminSettings
     enable_emoji_reaction
     check_lts_version_only
     enable_public_unlisted_visibility
+    unlocked_friend
   ).freeze
 
   INTEGER_KEYS = %i(
@@ -76,6 +77,7 @@ class Form::AdminSettings
     enable_emoji_reaction
     check_lts_version_only
     enable_public_unlisted_visibility
+    unlocked_friend
   ).freeze
 
   UPLOAD_KEYS = %i(

app/models/friend_domain.rb

@@ -0,0 +1,163 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: friend_domains
+#
+#  id                         :bigint(8)        not null, primary key
+#  domain                     :string           default(""), not null
+#  inbox_url                  :string           default(""), not null
+#  active_state               :integer          default("idle"), not null
+#  passive_state              :integer          default("idle"), not null
+#  active_follow_activity_id  :string
+#  passive_follow_activity_id :string
+#  available                  :boolean          default(TRUE), not null
+#  pseudo_relay               :boolean          default(FALSE), not null
+#  unlocked                   :boolean          default(FALSE), not null
+#  allow_all_posts            :boolean          default(TRUE), not null
+#  created_at                 :datetime         not null
+#  updated_at                 :datetime         not null
+#
+
+class FriendDomain < ApplicationRecord
+  validates :domain, presence: true, uniqueness: true, if: :will_save_change_to_domain?
+  validates :inbox_url, presence: true, uniqueness: true, if: :will_save_change_to_inbox_url?
+
+  enum active_state: { idle: 0, pending: 1, accepted: 2, rejected: 3 }, _prefix: :i_am
+  enum passive_state: { idle: 0, pending: 1, accepted: 2, rejected: 3 }, _prefix: :they_are
+
+  scope :by_domain_and_subdomains, ->(domain) { where(domain: Instance.by_domain_and_subdomains(domain).select(:domain)) }
+  scope :enabled, -> { where(available: true) }
+  scope :mutuals, -> { enabled.where(active_state: :accepted, passive_state: :accepted) }
+  scope :distributables, -> { mutuals.where(pseudo_relay: true) }
+  scope :deliver_locals, -> { enabled.where(active_state: :accepted) }
+  scope :free_receivings, -> { mutuals.where(allow_all_posts: true) }
+
+  before_destroy :ensure_disabled
+  after_commit :set_default_inbox_url
+
+  def mutual?
+    i_am_accepted? && they_are_accepted?
+  end
+
+  def follow!
+    activity_id = ActivityPub::TagManager.instance.generate_uri_for(nil)
+    payload     = Oj.dump(follow_activity(activity_id))
+
+    update!(active_state: :pending, active_follow_activity_id: activity_id)
+    DeliveryFailureTracker.reset!(inbox_url)
+    ActivityPub::DeliveryWorker.perform_async(payload, some_local_account.id, inbox_url)
+  end
+
+  def unfollow!
+    activity_id = ActivityPub::TagManager.instance.generate_uri_for(nil)
+    payload     = Oj.dump(unfollow_activity(activity_id))
+
+    update!(active_state: :idle, active_follow_activity_id: nil)
+    DeliveryFailureTracker.reset!(inbox_url)
+    ActivityPub::DeliveryWorker.perform_async(payload, some_local_account.id, inbox_url)
+  end
+
+  def accept!
+    return if they_are_idle?
+
+    activity_id = passive_follow_activity_id
+    payload     = Oj.dump(accept_follow_activity(activity_id))
+
+    update!(passive_state: :accepted)
+    DeliveryFailureTracker.reset!(inbox_url)
+    ActivityPub::DeliveryWorker.perform_async(payload, some_local_account.id, inbox_url)
+  end
+
+  def reject!
+    return if they_are_idle?
+
+    activity_id = passive_follow_activity_id
+    payload     = Oj.dump(reject_follow_activity(activity_id))
+
+    update!(passive_state: :rejected, passive_follow_activity_id: nil)
+    DeliveryFailureTracker.reset!(inbox_url)
+    ActivityPub::DeliveryWorker.perform_async(payload, some_local_account.id, inbox_url)
+  end
+
+  private
+
+  def default_inbox_url
+    "https://#{domain}/inbox"
+  end
+
+  def delete_for_friend!
+    activity_id = ActivityPub::TagManager.instance.generate_uri_for(nil)
+    payload     = Oj.dump(delete_follow_activity(activity_id))
+
+    DeliveryFailureTracker.reset!(inbox_url)
+    ActivityPub::DeliveryWorker.perform_async(payload, some_local_account.id, inbox_url)
+  end
+
+  def follow_activity(activity_id)
+    {
+      '@context': ActivityPub::TagManager::CONTEXT,
+      id: activity_id,
+      type: 'Follow',
+      actor: ActivityPub::TagManager.instance.uri_for(some_local_account),
+      object: ActivityPub::TagManager::COLLECTIONS[:public],
+    }
+  end
+
+  def unfollow_activity(activity_id)
+    {
+      '@context': ActivityPub::TagManager::CONTEXT,
+      id: activity_id,
+      type: 'Undo',
+      actor: ActivityPub::TagManager.instance.uri_for(some_local_account),
+      object: {
+        id: active_follow_activity_id,
+        type: 'Follow',
+        actor: ActivityPub::TagManager.instance.uri_for(some_local_account),
+        object: ActivityPub::TagManager::COLLECTIONS[:public],
+      },
+    }
+  end
+
+  def accept_follow_activity(activity_id)
+    {
+      '@context': ActivityPub::TagManager::CONTEXT,
+      id: "#{activity_id}#accepts/friends",
+      type: 'Accept',
+      actor: ActivityPub::TagManager.instance.uri_for(some_local_account),
+      object: activity_id,
+    }
+  end
+
+  def reject_follow_activity(activity_id)
+    {
+      '@context': ActivityPub::TagManager::CONTEXT,
+      id: "#{activity_id}#rejects/friends",
+      type: 'Reject',
+      actor: ActivityPub::TagManager.instance.uri_for(some_local_account),
+      object: activity_id,
+    }
+  end
+
+  def delete_follow_activity(activity_id)
+    {
+      '@context': ActivityPub::TagManager::CONTEXT,
+      id: "#{activity_id}#delete/friends",
+      type: 'Delete',
+      actor: ActivityPub::TagManager.instance.uri_for(some_local_account),
+      object: ActivityPub::TagManager::COLLECTIONS[:public],
+    }
+  end
+
+  def some_local_account
+    @some_local_account ||= Account.representative
+  end
+
+  def ensure_disabled
+    delete_for_friend! unless i_am_idle? && they_are_idle?
+  end
+
+  def set_default_inbox_url
+    self.inbox_url = default_inbox_url if inbox_url.blank?
+  end
+end

app/models/instance.rb

@@ -20,6 +20,7 @@ class Instance < ApplicationRecord
     belongs_to :domain_allow
     belongs_to :unavailable_domain # skipcq: RB-RL1031
     belongs_to :instance_info
+    belongs_to :friend_domain
   end
 
   scope :searchable, -> { where.not(domain: DomainBlock.select(:domain)) }

app/models/public_feed.rb

@@ -19,7 +19,7 @@ class PublicFeed
   # @param [Integer] min_id
   # @return [Array<Status>]
   def get(limit, max_id = nil, since_id = nil, min_id = nil)
-    scope = local_only? ? public_scope : global_timeline_only_scope
+    scope = public_scope
 
     scope.merge!(without_replies_scope) unless with_replies?
     scope.merge!(without_reblogs_scope) unless with_reblogs?
@@ -70,10 +70,6 @@ class PublicFeed
     Status.with_public_visibility.joins(:account).merge(Account.without_suspended.without_silenced)
   end
 
-  def global_timeline_only_scope
-    Status.with_global_timeline_visibility.joins(:account).merge(Account.without_suspended.without_silenced)
-  end
-
   def public_search_scope
     Status.with_public_search_visibility.joins(:account).merge(Account.without_suspended.without_silenced)
   end

app/models/status.rb

@@ -130,7 +130,6 @@ class Status < ApplicationRecord
   scope :without_reblogs, -> { where(statuses: { reblog_of_id: nil }) }
   scope :with_public_visibility, -> { where(visibility: [:public, :public_unlisted, :login]) }
   scope :with_public_search_visibility, -> { merge(where(visibility: [:public, :public_unlisted, :login]).or(Status.where(searchability: [:public, :public_unlisted]))) }
-  scope :with_global_timeline_visibility, -> { where(visibility: [:public, :login]) }
   scope :tagged_with, ->(tag_ids) { joins(:statuses_tags).where(statuses_tags: { tag_id: tag_ids }) }
   scope :excluding_silenced_accounts, -> { left_outer_joins(:account).where(accounts: { silenced_at: nil }) }
   scope :including_silenced_accounts, -> { left_outer_joins(:account).where.not(accounts: { silenced_at: nil }) }

app/models/user_settings.rb

@@ -80,6 +80,7 @@ class UserSettings
     setting :follow_request, default: true
     setting :report, default: true
     setting :pending_account, default: true
+    setting :pending_friend_server, default: true
     setting :trends, default: true
     setting :appeal, default: true
     setting :software_updates, default: 'critical', in: %w(none critical patch all)

app/policies/friend_server_policy.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class FriendServerPolicy < ApplicationPolicy
+  def update?
+    role.can?(:manage_federation)
+  end
+end

app/presenters/activitypub/activity_presenter.rb

@@ -4,13 +4,13 @@ class ActivityPub::ActivityPresenter < ActiveModelSerializers::Model
   attributes :id, :type, :actor, :published, :to, :cc, :virtual_object
 
   class << self
-    def from_status(status, use_bearcap: true, allow_inlining: true, for_misskey: false)
+    def from_status(status, use_bearcap: true, allow_inlining: true, for_misskey: false, for_friend: false)
       new.tap do |presenter|
         presenter.id        = ActivityPub::TagManager.instance.activity_uri_for(status)
         presenter.type      = status.reblog? ? 'Announce' : 'Create'
         presenter.actor     = ActivityPub::TagManager.instance.uri_for(status.account)
         presenter.published = status.created_at
-        presenter.to        = ActivityPub::TagManager.instance.to(status)
+        presenter.to        = for_friend ? ActivityPub::TagManager.instance.to_for_friend(status) : ActivityPub::TagManager.instance.to(status)
         presenter.cc        = for_misskey ? ActivityPub::TagManager.instance.cc_for_misskey(status) : ActivityPub::TagManager.instance.cc(status)
 
         presenter.virtual_object = begin

app/serializers/activitypub/activity_for_friend_serializer.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+class ActivityPub::ActivityForFriendSerializer < ActivityPub::Serializer
+  def self.serializer_for(model, options)
+    case model.class.name
+    when 'Status'
+      ActivityPub::NoteForFriendSerializer
+    when 'DeliverToDeviceService::EncryptedMessage'
+      ActivityPub::EncryptedMessageSerializer
+    else
+      super
+    end
+  end
+
+  attributes :id, :type, :actor, :published, :to, :cc
+
+  has_one :virtual_object, key: :object
+
+  def published
+    object.published.iso8601
+  end
+end

app/serializers/activitypub/note_for_friend_serializer.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class ActivityPub::NoteForFriendSerializer < ActivityPub::NoteSerializer
+  def to
+    ActivityPub::TagManager.instance.to_for_friend(object)
+  end
+
+  def searchable_by
+    ActivityPub::TagManager.instance.searchable_by_for_friend(object)
+  end
+end

app/services/block_domain_service.rb

@@ -24,6 +24,9 @@ class BlockDomainService < BaseService
       silence_accounts!
     elsif domain_block.suspend?
       suspend_accounts!
+      remove_friends!
+    elsif domain_block.reject_friend?
+      remove_friends!
     end
 
     DomainClearMediaWorker.perform_async(domain_block.id) if domain_block.reject_media?
@@ -41,6 +44,10 @@ class BlockDomainService < BaseService
     end
   end
 
+  def remove_friends!
+    blocked_friends.find_each(&:destroy)
+  end
+
   def blocked_domain
     domain_block.domain
   end
@@ -48,4 +55,8 @@ class BlockDomainService < BaseService
   def blocked_domain_accounts
     Account.by_domain_and_subdomains(blocked_domain)
   end
+
+  def blocked_friends
+    @blocked_friends ||= FriendDomain.by_domain_and_subdomains(blocked_domain)
+  end
 end

app/services/fan_out_on_write_service.rb

@@ -21,9 +21,6 @@ class FanOutOnWriteService < BaseService
     if broadcastable?
       fan_out_to_public_recipients!
       fan_out_to_public_streams!
-    elsif broadcastable_unlisted?
-      fan_out_to_public_recipients!
-      fan_out_to_public_unlisted_streams!
     elsif broadcastable_unlisted2?
       fan_out_to_unlisted_streams!
     end
@@ -75,11 +72,6 @@ class FanOutOnWriteService < BaseService
     broadcast_to_public_streams!
   end
 
-  def fan_out_to_public_unlisted_streams!
-    broadcast_to_hashtag_streams!
-    broadcast_to_public_unlisted_streams!
-  end
-
   def fan_out_to_unlisted_streams!
     broadcast_to_hashtag_streams!
   end
@@ -176,16 +168,6 @@ class FanOutOnWriteService < BaseService
     end
   end
 
-  def broadcast_to_public_unlisted_streams!
-    return if @status.reply? && @status.in_reply_to_account_id != @account.id
-
-    redis.publish(@status.local? ? 'timeline:public:local' : 'timeline:public:remote', anonymous_payload)
-
-    if @status.with_media?
-      redis.publish(@status.local? ? 'timeline:public:local:media' : 'timeline:public:remote:media', anonymous_payload)
-    end
-  end
-
   def deliver_to_conversation!
     AccountConversation.add_status(@account, @status) unless update?
   end
@@ -210,11 +192,7 @@ class FanOutOnWriteService < BaseService
   end
 
   def broadcastable?
-    (@status.public_visibility? || @status.login_visibility?) && !@status.reblog? && !@account.silenced?
-  end
-
-  def broadcastable_unlisted?
-    @status.public_unlisted_visibility? && !@status.reblog? && !@account.silenced?
+    (@status.public_visibility? || @status.public_unlisted_visibility? || @status.login_visibility?) && !@status.reblog? && !@account.silenced?
   end
 
   def broadcastable_unlisted2?

app/views/admin/domain_blocks/edit.html.haml

@@ -47,6 +47,9 @@
   .fields-group
     = f.input :reject_new_follow, as: :boolean, wrapper: :with_label, label: I18n.t('admin.domain_blocks.reject_new_follow'), hint: I18n.t('admin.domain_blocks.reject_new_follow_hint')
 
+  .fields-group
+    = f.input :reject_friend, as: :boolean, wrapper: :with_label, label: I18n.t('admin.domain_blocks.reject_friend'), hint: I18n.t('admin.domain_blocks.reject_friend_hint')
+
   .fields-group
     = f.input :detect_invalid_subscription, as: :boolean, wrapper: :with_label, label: I18n.t('admin.domain_blocks.detect_invalid_subscription'), hint: I18n.t('admin.domain_blocks.detect_invalid_subscription_hint')
 

app/views/admin/domain_blocks/new.html.haml

@@ -47,6 +47,9 @@
   .fields-group
     = f.input :reject_new_follow, as: :boolean, wrapper: :with_label, label: I18n.t('admin.domain_blocks.reject_new_follow'), hint: I18n.t('admin.domain_blocks.reject_new_follow_hint')
 
+  .fields-group
+    = f.input :reject_friend, as: :boolean, wrapper: :with_label, label: I18n.t('admin.domain_blocks.reject_friend'), hint: I18n.t('admin.domain_blocks.reject_friend_hint')
+
   .fields-group
     = f.input :detect_invalid_subscription, as: :boolean, wrapper: :with_label, label: I18n.t('admin.domain_blocks.detect_invalid_subscription'), hint: I18n.t('admin.domain_blocks.detect_invalid_subscription_hint')
 

app/views/admin/friend_servers/_friend_domain.html.haml

@@ -0,0 +1,41 @@
+%tr
+  %td
+    - unless friend.available
+      %span.negative-hint
+        = fa_icon('times')
+        = ' '
+        = t 'admin.friend_servers.disabled'
+    %samp= friend.domain
+  %td
+    - if friend.i_am_accepted?
+      %span.positive-hint
+        = fa_icon('check')
+        = ' '
+        = t 'admin.friend_servers.enabled'
+    - elsif friend.i_am_pending?
+      = fa_icon('hourglass')
+      = ' '
+      = t 'admin.friend_servers.pending'
+    - else
+      %span.negative-hint
+        = fa_icon('times')
+        = ' '
+        = t 'admin.friend_servers.disabled'
+  %td
+    - if friend.they_are_accepted?
+      %span.positive-hint
+        = fa_icon('check')
+        = ' '
+        = t 'admin.friend_servers.enabled'
+    - elsif friend.they_are_pending?
+      = fa_icon('hourglass')
+      = ' '
+      = t 'admin.friend_servers.pending'
+    - else
+      %span.negative-hint
+        = fa_icon('times')
+        = ' '
+        = t 'admin.friend_servers.disabled'
+  %td
+    = table_link_to 'pencil', t('admin.friend_servers.edit_friend'),   edit_admin_friend_server_path(friend)
+    = table_link_to 'times', t('admin.friend_servers.delete'), admin_friend_server_path(friend), method: :delete, data: { confirm: t('admin.accounts.are_you_sure') }

app/views/admin/friend_servers/_friend_fields.html.haml

@@ -0,0 +1,20 @@
+%p= t 'admin.friend_servers.edit.description'
+%hr.spacer/
+
+.fields-group
+  = f.input :domain, as: :string, wrapper: :with_label, required: true, disabled: !friend.id.nil?, label: t('admin.friend_servers.edit.domain')
+
+.fields-group
+  = f.input :inbox_url, as: :string, wrapper: :with_label, label: t('admin.friend_servers.edit.inbox_url'), hint: t('admin.friend_servers.edit.inbox_url_hint')
+
+.fields-group
+  = f.input :available, as: :boolean, wrapper: :with_label, label: t('admin.friend_servers.edit.available')
+
+.fields-group
+  = f.input :pseudo_relay, as: :boolean, wrapper: :with_label, label: t('admin.friend_servers.edit.pseudo_relay')
+
+.fields-group
+  = f.input :unlocked, as: :boolean, wrapper: :with_label, label: t('admin.friend_servers.edit.unlocked')
+
+.fields-group
+  = f.input :allow_all_posts, as: :boolean, wrapper: :with_label, label: t('admin.friend_servers.edit.allow_all_posts')

app/views/admin/friend_servers/edit.html.haml

@@ -0,0 +1,52 @@
+- content_for :page_title do
+  = t('admin.friend_servers.edit_friend')
+
+= simple_form_for @friend, url: admin_friend_server_path(@friend), method: :put do |f|
+  = render 'shared/error_messages', object: @friend
+  = render 'friend_fields', f: f, friend: @friend
+
+  .fields-group
+    %h4= t('admin.friend_servers.active_status')
+    .fields-group
+      - if @friend.i_am_accepted?
+        %span.positive-hint
+          = fa_icon('check')
+          = ' '
+          = t 'admin.friend_servers.enabled'
+      - elsif @friend.i_am_pending?
+        = fa_icon('hourglass')
+        = ' '
+        = t 'admin.friend_servers.pending'
+      - else
+        %span.negative-hint
+          = fa_icon('times')
+          = ' '
+          = t 'admin.friend_servers.disabled'
+      .action-buttons
+        %div
+          = link_to t('admin.friend_servers.follow'), follow_admin_friend_server_path(@friend), class: 'button', method: :post, data: { confirm: t('admin.accounts.are_you_sure') } if @friend.i_am_idle? || @friend.i_am_rejected?
+          = link_to t('admin.friend_servers.unfollow'), unfollow_admin_friend_server_path(@friend), class: 'button', method: :post, data: { confirm: t('admin.accounts.are_you_sure') } if @friend.i_am_pending? || @friend.i_am_accepted?
+
+    %h4= t('admin.friend_servers.passive_status')
+    .fields-gtoup
+      - if @friend.they_are_accepted?
+        %span.positive-hint
+          = fa_icon('check')
+          = ' '
+          = t 'admin.friend_servers.enabled'
+      - elsif @friend.they_are_pending?
+        = fa_icon('hourglass')
+        = ' '
+        = t 'admin.friend_servers.pending'
+      - else
+        %span.negative-hint
+          = fa_icon('times')
+          = ' '
+          = t 'admin.friend_servers.disabled'
+      .action-buttons
+        %div
+          = link_to t('admin.friend_servers.accept'), accept_admin_friend_server_path(@friend), class: 'button', method: :post, data: { confirm: t('admin.accounts.are_you_sure') } if @friend.they_are_pending?
+          = link_to t('admin.friend_servers.reject'), reject_admin_friend_server_path(@friend), class: 'button', method: :post, data: { confirm: t('admin.accounts.are_you_sure') } if @friend.they_are_pending?
+
+  .actions
+    = f.button :button, t('generic.save_changes'), type: :submit

app/views/admin/friend_servers/index.html.haml

@@ -0,0 +1,21 @@
+- content_for :page_title do
+  = t('admin.friend_servers.title')
+
+.simple_form
+  %p.hint= t('admin.friend_servers.description_html')
+  = link_to @friends.empty? ? t('admin.friend_servers.setup') : t('admin.friend_servers.add_new'), new_admin_friend_server_path, class: 'block-button'
+
+- unless @friends.empty?
+  %hr.spacer
+
+  .table-wrapper
+    %table.table
+      %thead
+        %tr
+          %th= t('admin.friend_servers.domain')
+          %th= t('admin.friend_servers.active_status')
+          %th= t('admin.friend_servers.passive_status')
+          %th
+      %tbody
+        - @friends.each do |friend|
+          = render 'friend_domain', friend: friend

app/views/admin/friend_servers/new.html.haml

@@ -0,0 +1,9 @@
+- content_for :page_title do
+  = t('admin.friend_servers.add_new')
+
+= simple_form_for @friend, url: admin_friend_servers_path do |f|
+  = render 'shared/error_messages', object: @friend
+  = render 'friend_fields', f: f, friend: @friend
+
+  .actions
+    = f.button :button, t('admin.friend_servers.save_and_enable'), type: :submit

app/views/admin/settings/discovery/show.html.haml

@@ -45,6 +45,11 @@
   .fields-group
     = f.input :enable_public_unlisted_visibility, as: :boolean, wrapper: :with_label, kmyblue: true, hint: false
 
+  %h4= t('admin.settings.discovery.friend_servers')
+
+  .fields-group
+    = f.input :unlocked_friend, as: :boolean, wrapper: :with_label, kmyblue: true, hint: false
+
   %h4= t('admin.settings.discovery.publish_statistics')
 
   .fields-group

app/views/admin_mailer/new_pending_friend_server.text.erb

@@ -0,0 +1,5 @@
+<%= raw t('application_mailer.salutation', name: display_name(@me)) %>
+
+<%= raw t('admin_mailer.new_pending_friend_server.body', domain: @friend.domain) %>
+
+<%= raw t('application_mailer.view')%> <%= admin_friend_servers_url %>

app/views/settings/preferences/notifications/show.html.haml

@@ -22,13 +22,14 @@
     .fields-group
       = ff.input :always_send_emails, wrapper: :with_label, label: I18n.t('simple_form.labels.defaults.setting_always_send_emails'), hint: I18n.t('simple_form.hints.defaults.setting_always_send_emails')
 
-    - if current_user.can?(:manage_reports, :manage_appeals, :manage_users, :manage_taxonomies) || (SoftwareUpdate.check_enabled? && current_user.can?(:view_devops))
+    - if current_user.can?(:manage_reports, :manage_appeals, :manage_users, :manage_taxonomies, :manage_federation) || (SoftwareUpdate.check_enabled? && current_user.can?(:view_devops))
       %h4= t 'notifications.administration_emails'
 
       .fields-group
         = ff.input :'notification_emails.report', wrapper: :with_label, label: I18n.t('simple_form.labels.notification_emails.report') if current_user.can?(:manage_reports)
         = ff.input :'notification_emails.appeal', as: :boolean, wrapper: :with_label, label: I18n.t('simple_form.labels.notification_emails.appeal') if current_user.can?(:manage_appeals)
         = ff.input :'notification_emails.pending_account', wrapper: :with_label, label: I18n.t('simple_form.labels.notification_emails.pending_account') if current_user.can?(:manage_users)
+        = ff.input :'notification_emails.pending_friend_server', as: :boolean, wrapper: :with_label, kmyblue: true, label: I18n.t('simple_form.labels.notification_emails.pending_friend_server') if current_user.can?(:manage_federation)
         = ff.input :'notification_emails.trends', wrapper: :with_label, label: I18n.t('simple_form.labels.notification_emails.trending_tag') if current_user.can?(:manage_taxonomies)
 
       - if SoftwareUpdate.check_enabled? && current_user.can?(:view_devops)

app/workers/activitypub/distribution_worker.rb

@@ -22,6 +22,10 @@ class ActivityPub::DistributionWorker < ActivityPub::RawDistributionWorker
     @inboxes_for_misskey ||= status_reach_finder.inboxes_for_misskey
   end
 
+  def inboxes_for_friend
+    @inboxes_for_friend ||= status_reach_finder.inboxes_for_friend
+  end
+
   def status_reach_finder
     @status_reach_finder ||= StatusReachFinder.new(@status)
   end
@@ -34,6 +38,10 @@ class ActivityPub::DistributionWorker < ActivityPub::RawDistributionWorker
     @payload_for_misskey ||= Oj.dump(serialize_payload(activity_for_misskey, ActivityPub::ActivityForMisskeySerializer, signer: @account))
   end
 
+  def payload_for_friend
+    @payload_for_friend ||= Oj.dump(serialize_payload(activity_for_friend, ActivityPub::ActivityForFriendSerializer, signer: @account))
+  end
+
   def activity
     ActivityPub::ActivityPresenter.from_status(@status)
   end
@@ -42,6 +50,10 @@ class ActivityPub::DistributionWorker < ActivityPub::RawDistributionWorker
     ActivityPub::ActivityPresenter.from_status(@status, for_misskey: true)
   end
 
+  def activity_for_friend
+    ActivityPub::ActivityPresenter.from_status(@status, for_friend: true)
+  end
+
   def options
     { 'synchronize_followers' => @status.private_visibility? }
   end

app/workers/activitypub/raw_distribution_worker.rb

@@ -29,6 +29,12 @@ class ActivityPub::RawDistributionWorker
       end
     end
 
+    unless inboxes_for_friend.empty?
+      ActivityPub::DeliveryWorker.push_bulk(inboxes_for_friend, limit: 1_000) do |inbox_url|
+        [payload_for_friend, source_account_id, inbox_url, options]
+      end
+    end
+
     return if inboxes.empty?
 
     ActivityPub::DeliveryWorker.push_bulk(inboxes, limit: 1_000) do |inbox_url|
@@ -44,6 +50,10 @@ class ActivityPub::RawDistributionWorker
     payload
   end
 
+  def payload_for_friend
+    payload
+  end
+
   def source_account_id
     @account.id
   end
@@ -56,6 +66,10 @@ class ActivityPub::RawDistributionWorker
     []
   end
 
+  def inboxes_for_friend
+    []
+  end
+
   def options
     {}
   end