WIP: Implement FEP-7888 - conversation context

app/controllers/activitypub/contexts_controller.rb

@@ -2,15 +2,63 @@
 
 class ActivityPub::ContextsController < ActivityPub::BaseController
   before_action :set_conversation
+  before_action :set_items, only: :items
+
+  DESCENDANTS_LIMIT = 60
 
   def show
     expires_in 3.minutes, public: public_fetch_mode?
     render_with_cache json: @conversation, serializer: ActivityPub::ContextSerializer, adapter: ActivityPub::Adapter, content_type: 'application/activity+json'
   end
 
+  def items
+    expires_in 3.minutes, public: public_fetch_mode?
+    render_with_cache json: items_collection_presenter, serializer: ActivityPub::CollectionSerializer, adapter: ActivityPub::Adapter, content_type: 'application/activity+json'
+  end
+
   private
 
+  def account_required?
+    false
+  end
+
   def set_conversation
     @conversation = Conversation.local.find(params[:id])
   end
+
+  def set_items
+    @items = @conversation.statuses.distributable_visibility.paginate_by_min_id(DESCENDANTS_LIMIT, params[:min_id])
+  end
+
+  def items_collection_presenter
+    page = ActivityPub::CollectionPresenter.new(
+      id: context_items_url(@conversation, page_params),
+      type: :unordered,
+      part_of: context_items_url(@conversation),
+      next: next_page,
+      items: @items.map { |status| status.local? ? status : status.uri }
+    )
+
+    return page if page_requested?
+
+    ActivityPub::CollectionPresenter.new(
+      id: context_items_url(@conversation),
+      type: :unordered,
+      first: page
+    )
+  end
+
+  def page_requested?
+    truthy_param?(:page)
+  end
+
+  def next_page
+    return nil if @items.size < DESCENDANTS_LIMIT
+
+    context_items_url(@conversation, page: true, min_id: @items.last.id)
+  end
+
+  def page_params
+    params.permit(:page, :min_id)
+  end
 end

app/controllers/statuses_controller.rb

@@ -59,7 +59,7 @@ def set_link_headers
   def set_status
     @status = @account.statuses.find(params[:id])
 
-    if request.authorization.present? && request.authorization.match(/^Bearer /i)
+    if !@status.distributable? && request.authorization.present? && request.authorization.match(/^Bearer /i)
       raise Mastodon::NotPermittedError unless @status.capability_tokens.find_by(token: request.authorization.gsub(/^Bearer /i, ''))
     else
       authorize @status, :show?

app/lib/activitypub/tag_manager.rb

@@ -39,6 +39,8 @@ def uri_for(target)
     case target.object_type
     when :person
       target.instance_actor? ? instance_actor_url : account_url(target)
+    when :conversation
+      context_url(target)
     when :note, :comment, :activity
       return activity_account_status_url(target.account, target) if target.reblog?
 
@@ -68,6 +70,12 @@ def activity_uri_for(target)
     activity_account_status_url(target.account, target)
   end
 
+  def context_uri_for(target, page_params = nil)
+    raise ArgumentError, 'target must be a local activity' unless %i(note comment activity).include?(target.object_type) && target.local?
+
+    context_items_url(target.conversation, page_params)
+  end
+
   def replies_uri_for(target, page_params = nil)
     raise ArgumentError, 'target must be a local activity' unless %i(note comment activity).include?(target.object_type) && target.local?
 

app/models/user.rb

@@ -128,8 +128,6 @@ class User < ApplicationRecord
   scope :matches_ip, ->(value) { left_joins(:ips).where('user_ips.ip <<= ?', value).group('users.id') }
 
   before_validation :sanitize_role
-  before_validation :sanitize_time_zone
-  before_validation :sanitize_locale
   before_create :set_approved
   after_commit :send_pending_devise_notifications
   after_create_commit :trigger_webhooks

app/serializers/activitypub/context_serializer.rb

@@ -3,17 +3,38 @@
 class ActivityPub::ContextSerializer < ActivityPub::Serializer
   include RoutingHelper
 
-  attributes :id, :type, :inbox
+  attributes :id, :type, :first, :attributed_to
+
+  has_one :first, serializer: ActivityPub::CollectionSerializer
 
   def id
     ActivityPub::TagManager.instance.uri_for(object)
   end
 
+  def attributed_to
+    ActivityPub::TagManager.instance.uri_for(object.parent_account)
+  end
+
   def type
-    'Group'
+    'Collection'
   end
 
-  def inbox
-    account_inbox_url(object.parent_account)
+  def first
+    conversation_statuses = object.statuses[0..5]
+    last_status = conversation_statuses.last
+    conversation_statuses = conversation_statuses.pluck(:id, :uri)
+    last_id = conversation_statuses.last&.first
+    has_more = object.statuses.count > ActivityPub::ContextsController::DESCENDANTS_LIMIT
+
+    next_page = if has_more
+                  last_id ? ActivityPub::TagManager.instance.context_uri_for(last_status, page: true, min_id: last_id) : ActivityPub::TagManager.instance.context_uri_for(last_status, page: true, only_other_accounts: true)
+                end
+
+    ActivityPub::CollectionPresenter.new(
+      type: :unordered,
+      part_of: ActivityPub::TagManager.instance.uri_for(object),
+      items: conversation_statuses.map(&:second),
+      next: next_page
+    )
   end
 end

app/serializers/activitypub/note_serializer.rb

@@ -18,6 +18,7 @@ class ActivityPub::NoteSerializer < ActivityPub::Serializer
   has_many :virtual_attachments, key: :attachment
   has_many :virtual_tags, key: :tag
 
+  has_one :context
   has_one :replies, serializer: ActivityPub::CollectionSerializer, if: :local?
   has_one :likes, serializer: ActivityPub::CollectionSerializer, if: :local?
   has_one :shares, serializer: ActivityPub::CollectionSerializer, if: :local?
@@ -158,6 +159,7 @@ def conversation
 
   def context
     return if object.conversation.nil?
+    return if object.conversation.parent_status.nil?
 
     ActivityPub::TagManager.instance.uri_for(object.conversation)
   end

config/routes.rb

@@ -143,7 +143,9 @@ def redirect_with_vary(path)
   end
 
   resource :inbox, only: [:create], module: :activitypub
-  resources :contexts, only: [:show], module: :activitypub
+  resources :contexts, only: [:show], module: :activitypub do
+    resources :items, only: [:index], module: :activitypub
+  end
 
   constraints(encoded_path: /%40.*/) do
     get '/:encoded_path', to: redirect { |params|

spec/controllers/activitypub/contexts_controller_spec.rb

@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe ActivityPub::ContextsController do
+  let(:user) { Fabricate(:user) }
+  let(:conversation) { Fabricate(:conversation) }
+
+  before do
+    allow(controller).to receive(:signed_request_actor).and_return(nil)
+  end
+
+  describe 'GET #show' do
+    context 'with few statuses' do
+      before do
+        3.times do
+          Fabricate(:status, visibility: :private, account: user.account, conversation: conversation)
+        end
+      end
+
+      it 'does not include a next page link' do
+        get :show, params: { id: conversation.id }
+        json = JSON.parse(response.body)
+        expect(json['first']['next']).to be_nil
+      end
+    end
+
+    context 'with many statuses' do
+      before do
+        (ActivityPub::ContextsController::DESCENDANTS_LIMIT + 1).times do
+          Fabricate(:status, visibility: :private, account: user.account, conversation: conversation)
+        end
+      end
+
+      it 'includes a next page link' do
+        get :show, params: { id: conversation.id }
+        json = JSON.parse(response.body)
+        expect(json['first']['next']).to_not be_nil
+      end
+    end
+  end
+end

spec/fabricators/conversation_fabricator.rb

@@ -1,3 +1,5 @@
 # frozen_string_literal: true
 
-Fabricator(:conversation)
+Fabricator(:conversation) do
+  parent_account { Fabricate(:account) }
+end

spec/serializers/activitypub/note_serializer_spec.rb

@@ -7,11 +7,11 @@
 
   let!(:account) { Fabricate(:account) }
   let!(:other) { Fabricate(:account) }
-  let!(:parent) { Fabricate(:status, account: account, visibility: :public, language: 'zh-TW') }
-  let!(:reply_by_account_first) { Fabricate(:status, account: account, thread: parent, visibility: :public) }
-  let!(:reply_by_account_next) { Fabricate(:status, account: account, thread: parent, visibility: :public) }
-  let!(:reply_by_other_first) { Fabricate(:status, account: other, thread: parent, visibility: :public) }
-  let!(:reply_by_account_third) { Fabricate(:status, account: account, thread: parent, visibility: :public) }
+  let!(:parent) { Fabricate(:status, account: account, visibility: :private, language: 'zh-TW') }
+  let!(:reply_by_account_first) { Fabricate(:status, account: account, thread: parent, visibility: :private) }
+  let!(:reply_by_account_next) { Fabricate(:status, account: account, thread: parent, visibility: :private) }
+  let!(:reply_by_other_first) { Fabricate(:status, account: other, thread: parent, visibility: :private) }
+  let!(:reply_by_account_third) { Fabricate(:status, account: account, thread: parent, visibility: :private) }
   let!(:reply_by_account_visibility_direct) { Fabricate(:status, account: account, thread: parent, visibility: :direct) }
 
   it 'has the expected shape and replies collection' do
@@ -22,16 +22,17 @@
       'contentMap' => include({
         'zh-TW' => a_kind_of(String),
       }),
+      'context' => ActivityPub::TagManager.instance.uri_for(parent.conversation),
       'replies' => replies_collection_values,
     })
   end
 
   def replies_collection_values
     include(
-      'type' => eql('Collection'),
+      'type' => 'Collection',
       'first' => include(
-        'type' => eql('CollectionPage'),
-        'items' => reply_items
+        'type' => 'CollectionPage',
+        'items' => []
       )
     )
   end