activitypub-academy/app/services/activitypub/fetch_remote_status_service.rb
Claire 3f9b28ce26
Add support for fetching Create and Announce activities by URI (#16383)
* Add support for fetching Create and Announce activities by URI

This should improve compatibility with ZAP and offer a way to fetch boosts,
which is currently not possible.

* Add tests
2021-10-21 01:14:04 +02:00

61 lines
1.8 KiB
Ruby

# frozen_string_literal: true
class ActivityPub::FetchRemoteStatusService < BaseService
include JsonLdHelper
# Should be called when uri has already been checked for locality
def call(uri, id: true, prefetched_body: nil, on_behalf_of: nil)
@json = begin
if prefetched_body.nil?
fetch_resource(uri, id, on_behalf_of)
else
body_to_json(prefetched_body, compare_id: id ? uri : nil)
end
end
return unless supported_context?
actor_id = nil
activity_json = nil
if expected_object_type?
actor_id = value_or_id(first_of_value(@json['attributedTo']))
activity_json = { 'type' => 'Create', 'actor' => actor_id, 'object' => @json }
elsif expected_activity_type?
actor_id = value_or_id(first_of_value(@json['actor']))
activity_json = @json
end
return if activity_json.nil? || !trustworthy_attribution?(@json['id'], actor_id)
actor = ActivityPub::TagManager.instance.uri_to_resource(actor_id, Account)
actor = ActivityPub::FetchRemoteAccountService.new.call(actor_id, id: true) if actor.nil? || needs_update?(actor)
return if actor.nil? || actor.suspended?
ActivityPub::Activity.factory(activity_json, actor).perform
end
private
def trustworthy_attribution?(uri, attributed_to)
return false if uri.nil? || attributed_to.nil?
Addressable::URI.parse(uri).normalized_host.casecmp(Addressable::URI.parse(attributed_to).normalized_host).zero?
end
def supported_context?
super(@json)
end
def expected_activity_type?
equals_or_includes_any?(@json['type'], %w(Create Announce))
end
def expected_object_type?
equals_or_includes_any?(@json['type'], ActivityPub::Activity::Create::SUPPORTED_TYPES + ActivityPub::Activity::Create::CONVERTED_TYPES)
end
def needs_update?(actor)
actor.possibly_stale?
end
end