friendica/src/Protocol/ActivityPub.php
2020-07-29 05:12:16 +00:00

263 lines
7.9 KiB
PHP

<?php
/**
* @copyright Copyright (C) 2020, Friendica
*
* @license GNU AGPL version 3 or any later version
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
*/
namespace Friendica\Protocol;
use Friendica\Core\Protocol;
use Friendica\Database\DBA;
use Friendica\DI;
use Friendica\Model\APContact;
use Friendica\Model\User;
use Friendica\Util\HTTPSignature;
use Friendica\Util\JsonLD;
/**
* ActivityPub Protocol class
*
* The ActivityPub Protocol is a message exchange protocol defined by the W3C.
* https://www.w3.org/TR/activitypub/
* https://www.w3.org/TR/activitystreams-core/
* https://www.w3.org/TR/activitystreams-vocabulary/
*
* https://blog.joinmastodon.org/2018/06/how-to-implement-a-basic-activitypub-server/
* https://blog.joinmastodon.org/2018/07/how-to-make-friends-and-verify-requests/
*
* Digest: https://tools.ietf.org/html/rfc5843
* https://tools.ietf.org/html/draft-cavage-http-signatures-10#ref-15
*
* Mastodon implementation of supported activities:
* https://github.com/tootsuite/mastodon/blob/master/app/lib/activitypub/activity.rb#L26
*
* Funkwhale:
* http://docs-funkwhale-funkwhale-549-music-federation-documentation.preview.funkwhale.audio/federation/index.html
*
* To-do:
* - Polling the outboxes for missing content?
*
* Missing parts from DFRN:
* - Public Forum
* - Private Forum
* - Relocation
*/
class ActivityPub
{
const PUBLIC_COLLECTION = 'https://www.w3.org/ns/activitystreams#Public';
const CONTEXT = ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1',
['vcard' => 'http://www.w3.org/2006/vcard/ns#',
'dfrn' => 'http://purl.org/macgirvin/dfrn/1.0/',
'diaspora' => 'https://diasporafoundation.org/ns/',
'litepub' => 'http://litepub.social/ns#',
'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers',
'sensitive' => 'as:sensitive', 'Hashtag' => 'as:Hashtag',
'directMessage' => 'litepub:directMessage']];
const ACCOUNT_TYPES = ['Person', 'Organization', 'Service', 'Group', 'Application'];
/**
* Checks if the web request is done for the AP protocol
*
* @return bool is it AP?
*/
public static function isRequest()
{
return stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/activity+json') ||
stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/ld+json');
}
/**
* Fetches ActivityPub content from the given url
*
* @param string $url content url
* @param integer $uid User ID for the signature
* @return array
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function fetchContent(string $url, int $uid = 0)
{
if (empty($uid)) {
$user = User::getFirstAdmin(['uid']);
if (empty($user['uid'])) {
// When the system setup is missing an admin we just take the first user
$condition = ['verified' => true, 'blocked' => false, 'account_removed' => false, 'account_expired' => false];
$user = DBA::selectFirst('user', ['uid'], $condition);
}
if (!empty($user['uid'])) {
$uid = $user['uid'];
}
}
return HTTPSignature::fetch($url, $uid);
}
private static function getAccountType($apcontact)
{
$accounttype = -1;
switch($apcontact['type']) {
case 'Person':
$accounttype = User::ACCOUNT_TYPE_PERSON;
break;
case 'Organization':
$accounttype = User::ACCOUNT_TYPE_ORGANISATION;
break;
case 'Service':
$accounttype = User::ACCOUNT_TYPE_NEWS;
break;
case 'Group':
$accounttype = User::ACCOUNT_TYPE_COMMUNITY;
break;
case 'Application':
$accounttype = User::ACCOUNT_TYPE_RELAY;
break;
}
return $accounttype;
}
/**
* Fetches a profile from the given url into an array that is compatible to Probe::uri
*
* @param string $url profile url
* @param boolean $update Update the profile
* @return array
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
* @throws \ImagickException
*/
public static function probeProfile($url, $update = true)
{
$apcontact = APContact::getByURL($url, $update);
if (empty($apcontact)) {
return [];
}
$profile = ['network' => Protocol::ACTIVITYPUB];
$profile['nick'] = $apcontact['nick'];
$profile['name'] = $apcontact['name'];
$profile['guid'] = $apcontact['uuid'];
$profile['url'] = $apcontact['url'];
$profile['addr'] = $apcontact['addr'];
$profile['alias'] = $apcontact['alias'];
$profile['following'] = $apcontact['following'];
$profile['followers'] = $apcontact['followers'];
$profile['inbox'] = $apcontact['inbox'];
$profile['outbox'] = $apcontact['outbox'];
$profile['sharedinbox'] = $apcontact['sharedinbox'];
$profile['photo'] = $apcontact['photo'];
$profile['account-type'] = self::getAccountType($apcontact);
$profile['community'] = ($profile['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
// $profile['keywords']
// $profile['location']
$profile['about'] = $apcontact['about'];
$profile['batch'] = $apcontact['sharedinbox'];
$profile['notify'] = $apcontact['inbox'];
$profile['poll'] = $apcontact['outbox'];
$profile['pubkey'] = $apcontact['pubkey'];
$profile['subscribe'] = $apcontact['subscribe'];
$profile['baseurl'] = $apcontact['baseurl'];
$profile['gsid'] = $apcontact['gsid'];
// Remove all "null" fields
foreach ($profile as $field => $content) {
if (is_null($content)) {
unset($profile[$field]);
}
}
return $profile;
}
/**
* Fetches activities from the outbox of a given profile and processes it
*
* @param string $url
* @param integer $uid User ID
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function fetchOutbox($url, $uid)
{
$data = self::fetchContent($url, $uid);
if (empty($data)) {
return;
}
if (!empty($data['orderedItems'])) {
$items = $data['orderedItems'];
} elseif (!empty($data['first']['orderedItems'])) {
$items = $data['first']['orderedItems'];
} elseif (!empty($data['first'])) {
self::fetchOutbox($data['first'], $uid);
return;
} else {
$items = [];
}
foreach ($items as $activity) {
$ldactivity = JsonLD::compact($activity);
ActivityPub\Receiver::processActivity($ldactivity, '', $uid, true);
}
}
/**
* Fetch items from AP endpoints
*
* @param string $url Address of the endpoint
* @param integer $uid Optional user id
* @return array Endpoint items
*/
public static function fetchItems(string $url, int $uid = 0)
{
$data = self::fetchContent($url, $uid);
if (empty($data)) {
return [];
}
if (!empty($data['orderedItems'])) {
$items = $data['orderedItems'];
} elseif (!empty($data['first']['orderedItems'])) {
$items = $data['first']['orderedItems'];
} elseif (!empty($data['first']) && is_string($data['first']) && ($data['first'] != $url)) {
return self::fetchItems($data['first'], $uid);
} else {
return [];
}
if (!empty($data['next']) && is_string($data['next'])) {
$items = array_merge($items, self::fetchItems($data['next'], $uid));
}
return $items;
}
/**
* Checks if the given contact url does support ActivityPub
*
* @param string $url profile url
* @param boolean $update true = always update, false = never update, null = update when not found or outdated
* @return boolean
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
* @throws \ImagickException
*/
public static function isSupportedByContactUrl($url, $update = null)
{
return !empty(APContact::getByURL($url, $update));
}
}