app/controllers/statuses_controller.rb

   1 # frozen_string_literal: true
   2
   3 class StatusesController < ApplicationController
   4   include SignatureAuthentication
   5   include Authorization
   6
   7   ANCESTORS_LIMIT         = 40
   8   DESCENDANTS_LIMIT       = 60
   9   DESCENDANTS_DEPTH_LIMIT = 20
  10
  11   layout 'public'
  12
  13   before_action :set_account
  14   before_action :set_status
  15   before_action :set_instance_presenter
  16   before_action :set_link_headers
  17   before_action :check_account_suspension
  18   before_action :redirect_to_original, only: [:show]
  19   before_action :set_referrer_policy_header, only: [:show]
  20   before_action :set_cache_headers
  21
  22   def show
  23     respond_to do |format|
  24       format.html do
  25         @body_classes = 'with-modals'
  26
  27         set_ancestors
  28         set_descendants
  29
  30         render 'stream_entries/show'
  31       end
  32
  33       format.json do
  34         skip_session! unless @stream_entry.hidden?
  35
  36         render_cached_json(['activitypub', 'note', @status], content_type: 'application/activity+json', public: !@stream_entry.hidden?) do
  37           ActiveModelSerializers::SerializableResource.new(@status, serializer: ActivityPub::NoteSerializer, adapter: ActivityPub::Adapter)
  38         end
  39       end
  40     end
  41   end
  42
  43   def activity
  44     skip_session!
  45
  46     render_cached_json(['activitypub', 'activity', @status], content_type: 'application/activity+json', public: !@stream_entry.hidden?) do
  47       ActiveModelSerializers::SerializableResource.new(@status, serializer: ActivityPub::ActivitySerializer, adapter: ActivityPub::Adapter)
  48     end
  49   end
  50
  51   def embed
  52     raise ActiveRecord::RecordNotFound if @status.hidden?
  53
  54     skip_session!
  55     expires_in 180, public: true
  56     response.headers['X-Frame-Options'] = 'ALLOWALL'
  57     @autoplay = ActiveModel::Type::Boolean.new.cast(params[:autoplay])
  58
  59     render 'stream_entries/embed', layout: 'embedded'
  60   end
  61
  62   private
  63
  64   def create_descendant_thread(depth, statuses)
  65     if depth < DESCENDANTS_DEPTH_LIMIT
  66       { statuses: statuses }
  67     else
  68       next_status = statuses.pop
  69       { statuses: statuses, next_status: next_status }
  70     end
  71   end
  72
  73   def set_account
  74     @account = Account.find_local!(params[:account_username])
  75   end
  76
  77   def set_ancestors
  78     @ancestors     = @status.reply? ? cache_collection(@status.ancestors(ANCESTORS_LIMIT, current_account), Status) : []
  79     @next_ancestor = @ancestors.size < ANCESTORS_LIMIT ? nil : @ancestors.shift
  80   end
  81
  82   def set_descendants
  83     @max_descendant_thread_id   = params[:max_descendant_thread_id]&.to_i
  84     @since_descendant_thread_id = params[:since_descendant_thread_id]&.to_i
  85
  86     descendants = cache_collection(
  87       @status.descendants(
  88         DESCENDANTS_LIMIT,
  89         current_account,
  90         @max_descendant_thread_id,
  91         @since_descendant_thread_id,
  92         DESCENDANTS_DEPTH_LIMIT
  93       ),
  94       Status
  95     )
  96
  97     @descendant_threads = []
  98
  99     if descendants.present?
 100       statuses = [descendants.first]
 101       depth    = 1
 102
 103       descendants.drop(1).each_with_index do |descendant, index|
 104         if descendants[index].id == descendant.in_reply_to_id
 105           depth += 1
 106           statuses << descendant
 107         else
 108           @descendant_threads << create_descendant_thread(depth, statuses)
 109
 110           @descendant_threads.reverse_each do |descendant_thread|
 111             statuses = descendant_thread[:statuses]
 112
 113             index = statuses.find_index do |thread_status|
 114               thread_status.id == descendant.in_reply_to_id
 115             end
 116
 117             if index.present?
 118               depth += index - statuses.size
 119               break
 120             end
 121
 122             depth -= statuses.size
 123           end
 124
 125           statuses = [descendant]
 126         end
 127       end
 128
 129       @descendant_threads << create_descendant_thread(depth, statuses)
 130     end
 131
 132     @max_descendant_thread_id = @descendant_threads.pop[:statuses].first.id if descendants.size >= DESCENDANTS_LIMIT
 133   end
 134
 135   def set_link_headers
 136     response.headers['Link'] = LinkHeader.new(
 137       [
 138         [account_stream_entry_url(@account, @status.stream_entry, format: 'atom'), [%w(rel alternate), %w(type application/atom+xml)]],
 139         [ActivityPub::TagManager.instance.uri_for(@status), [%w(rel alternate), %w(type application/activity+json)]],
 140       ]
 141     )
 142   end
 143
 144   def set_status
 145     @status       = @account.statuses.find(params[:id])
 146     @stream_entry = @status.stream_entry
 147     @type         = @stream_entry.activity_type.downcase
 148
 149     authorize @status, :show?
 150   rescue Mastodon::NotPermittedError
 151     # Reraise in order to get a 404
 152     raise ActiveRecord::RecordNotFound
 153   end
 154
 155   def set_instance_presenter
 156     @instance_presenter = InstancePresenter.new
 157   end
 158
 159   def check_account_suspension
 160     gone if @account.suspended?
 161   end
 162
 163   def redirect_to_original
 164     redirect_to ::TagManager.instance.url_for(@status.reblog) if @status.reblog?
 165   end
 166
 167   def set_referrer_policy_header
 168     return if @status.public_visibility? || @status.unlisted_visibility?
 169     response.headers['Referrer-Policy'] = 'origin'
 170   end
 171 end