catstodon/app/controllers/statuses_controller.rb
Ben Lubar c3d1594576 Reduce server load caused by anonymous viewing. (#9059)
Do not start a session if the current user is not logged in for public-facing pages.

Mark pages that don't care about sessions as publicly cacheable.

Keep the max age as 0 so proxies and browsers will still try to retrieve an updated version but can still fall back to the stale version if the site is down or too slow.

Fixes #9035.
2019-03-17 15:39:25 +01:00

232 lines
7 KiB
Ruby

# frozen_string_literal: true
class StatusesController < ApplicationController
include SignatureAuthentication
include Authorization
ANCESTORS_LIMIT = 40
DESCENDANTS_LIMIT = 60
DESCENDANTS_DEPTH_LIMIT = 20
layout 'public'
before_action :set_account
before_action :set_status
before_action :set_instance_presenter
before_action :set_link_headers
before_action :check_account_suspension
before_action :redirect_to_original, only: [:show]
before_action :set_referrer_policy_header, only: [:show]
before_action :set_cache_headers
before_action :set_replies, only: [:replies]
content_security_policy only: :embed do |p|
p.frame_ancestors(false)
end
def show
respond_to do |format|
format.html do
mark_cacheable! unless user_signed_in?
@body_classes = 'with-modals'
set_ancestors
set_descendants
render 'stream_entries/show'
end
format.json do
mark_cacheable! unless @stream_entry.hidden?
render_cached_json(['activitypub', 'note', @status], content_type: 'application/activity+json', public: !@stream_entry.hidden?) do
ActiveModelSerializers::SerializableResource.new(@status, serializer: ActivityPub::NoteSerializer, adapter: ActivityPub::Adapter)
end
end
end
end
def activity
skip_session!
render_cached_json(['activitypub', 'activity', @status], content_type: 'application/activity+json', public: !@stream_entry.hidden?) do
ActiveModelSerializers::SerializableResource.new(@status, serializer: ActivityPub::ActivitySerializer, adapter: ActivityPub::Adapter)
end
end
def embed
raise ActiveRecord::RecordNotFound if @status.hidden?
skip_session!
expires_in 180, public: true
response.headers['X-Frame-Options'] = 'ALLOWALL'
@autoplay = ActiveModel::Type::Boolean.new.cast(params[:autoplay])
render 'stream_entries/embed', layout: 'embedded'
end
def replies
skip_session!
render json: replies_collection_presenter,
serializer: ActivityPub::CollectionSerializer,
adapter: ActivityPub::Adapter,
content_type: 'application/activity+json',
skip_activities: true
end
private
def replies_collection_presenter
page = ActivityPub::CollectionPresenter.new(
id: replies_account_status_url(@account, @status, page_params),
type: :unordered,
part_of: replies_account_status_url(@account, @status),
next: next_page,
items: @replies.map { |status| status.local ? status : status.id }
)
if page_requested?
page
else
ActivityPub::CollectionPresenter.new(
id: replies_account_status_url(@account, @status),
type: :unordered,
first: page
)
end
end
def create_descendant_thread(starting_depth, statuses)
depth = starting_depth + statuses.size
if depth < DESCENDANTS_DEPTH_LIMIT
{ statuses: statuses, starting_depth: starting_depth }
else
next_status = statuses.pop
{ statuses: statuses, starting_depth: starting_depth, next_status: next_status }
end
end
def set_account
@account = Account.find_local!(params[:account_username])
end
def set_ancestors
@ancestors = @status.reply? ? cache_collection(@status.ancestors(ANCESTORS_LIMIT, current_account), Status) : []
@next_ancestor = @ancestors.size < ANCESTORS_LIMIT ? nil : @ancestors.shift
end
def set_descendants
@max_descendant_thread_id = params[:max_descendant_thread_id]&.to_i
@since_descendant_thread_id = params[:since_descendant_thread_id]&.to_i
descendants = cache_collection(
@status.descendants(
DESCENDANTS_LIMIT,
current_account,
@max_descendant_thread_id,
@since_descendant_thread_id,
DESCENDANTS_DEPTH_LIMIT
),
Status
)
@descendant_threads = []
if descendants.present?
statuses = [descendants.first]
starting_depth = 0
descendants.drop(1).each_with_index do |descendant, index|
if descendants[index].id == descendant.in_reply_to_id
statuses << descendant
else
@descendant_threads << create_descendant_thread(starting_depth, statuses)
# The thread is broken, assume it's a reply to the root status
starting_depth = 0
# ... unless we can find its ancestor in one of the already-processed threads
@descendant_threads.reverse_each do |descendant_thread|
statuses = descendant_thread[:statuses]
index = statuses.find_index do |thread_status|
thread_status.id == descendant.in_reply_to_id
end
if index.present?
starting_depth = descendant_thread[:starting_depth] + index + 1
break
end
end
statuses = [descendant]
end
end
@descendant_threads << create_descendant_thread(starting_depth, statuses)
end
@max_descendant_thread_id = @descendant_threads.pop[:statuses].first.id if descendants.size >= DESCENDANTS_LIMIT
end
def set_link_headers
response.headers['Link'] = LinkHeader.new(
[
[account_stream_entry_url(@account, @status.stream_entry, format: 'atom'), [%w(rel alternate), %w(type application/atom+xml)]],
[ActivityPub::TagManager.instance.uri_for(@status), [%w(rel alternate), %w(type application/activity+json)]],
]
)
end
def set_status
@status = @account.statuses.find(params[:id])
@stream_entry = @status.stream_entry
@type = @stream_entry.activity_type.downcase
authorize @status, :show?
rescue Mastodon::NotPermittedError
# Reraise in order to get a 404
raise ActiveRecord::RecordNotFound
end
def set_instance_presenter
@instance_presenter = InstancePresenter.new
end
def check_account_suspension
gone if @account.suspended?
end
def redirect_to_original
redirect_to ::TagManager.instance.url_for(@status.reblog) if @status.reblog?
end
def set_referrer_policy_header
return if @status.public_visibility? || @status.unlisted_visibility?
response.headers['Referrer-Policy'] = 'origin'
end
def page_requested?
params[:page] == 'true'
end
def set_replies
@replies = page_params[:other_accounts] ? Status.where.not(account_id: @account.id) : @account.statuses
@replies = @replies.where(in_reply_to_id: @status.id, visibility: [:public, :unlisted])
@replies = @replies.paginate_by_min_id(DESCENDANTS_LIMIT, params[:min_id])
end
def next_page
last_reply = @replies.last
return if last_reply.nil?
same_account = last_reply.account_id == @account.id
return unless same_account || @replies.size == DESCENDANTS_LIMIT
same_account = false unless @replies.size == DESCENDANTS_LIMIT
replies_account_status_url(@account, @status, page: true, min_id: last_reply.id, other_accounts: !same_account)
end
def page_params
{ page: true, other_accounts: params[:other_accounts], min_id: params[:min_id] }.compact
end
end