src/Protocol/ActivityPub.php

   1 <?php
   2 /**
   3  * @file src/Protocol/ActivityPub.php
   4  */
   5 namespace Friendica\Protocol;
   6
   7 use Friendica\Util\JsonLD;
   8 use Friendica\Util\Network;
   9 use Friendica\Core\Protocol;
  10 use Friendica\Model\APContact;
  11 use Friendica\Model\User;
  12 use Friendica\Util\HTTPSignature;
  13
  14 /**
  15  * ActivityPub Protocol class
  16  *
  17  * The ActivityPub Protocol is a message exchange protocol defined by the W3C.
  18  * https://www.w3.org/TR/activitypub/
  19  * https://www.w3.org/TR/activitystreams-core/
  20  * https://www.w3.org/TR/activitystreams-vocabulary/
  21  *
  22  * https://blog.joinmastodon.org/2018/06/how-to-implement-a-basic-activitypub-server/
  23  * https://blog.joinmastodon.org/2018/07/how-to-make-friends-and-verify-requests/
  24  *
  25  * Digest: https://tools.ietf.org/html/rfc5843
  26  * https://tools.ietf.org/html/draft-cavage-http-signatures-10#ref-15
  27  *
  28  * Mastodon implementation of supported activities:
  29  * https://github.com/tootsuite/mastodon/blob/master/app/lib/activitypub/activity.rb#L26
  30  *
  31  * Funkwhale:
  32  * http://docs-funkwhale-funkwhale-549-music-federation-documentation.preview.funkwhale.audio/federation/index.html
  33  *
  34  * To-do:
  35  * - Polling the outboxes for missing content?
  36  *
  37  * Missing parts from DFRN:
  38  * - Public Forum
  39  * - Private Forum
  40  * - Relocation
  41  */
  42 class ActivityPub
  43 {
  44         const PUBLIC_COLLECTION = 'https://www.w3.org/ns/activitystreams#Public';
  45         const CONTEXT = ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1',
  46                 ['vcard' => 'http://www.w3.org/2006/vcard/ns#',
  47                 'dfrn' => 'http://purl.org/macgirvin/dfrn/1.0/',
  48                 'diaspora' => 'https://diasporafoundation.org/ns/',
  49                 'litepub' => 'http://litepub.social/ns#',
  50                 'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers',
  51                 'sensitive' => 'as:sensitive', 'Hashtag' => 'as:Hashtag',
  52                 'directMessage' => 'litepub:directMessage']];
  53         const ACCOUNT_TYPES = ['Person', 'Organization', 'Service', 'Group', 'Application'];
  54         /**
  55          * Checks if the web request is done for the AP protocol
  56          *
  57          * @return bool is it AP?
  58          */
  59         public static function isRequest()
  60         {
  61                 return stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/activity+json') ||
  62                         stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/ld+json');
  63         }
  64
  65         /**
  66          * Fetches ActivityPub content from the given url
  67          *
  68          * @param string  $url content url
  69          * @param integer $uid User ID for the signature
  70          * @return array
  71          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  72          */
  73         public static function fetchContent($url, $uid = 0)
  74         {
  75                 if (!empty($uid)) {
  76                         return HTTPSignature::fetch($url, $uid);
  77                 }
  78
  79                 $curlResult = Network::curl($url, false, ['accept_content' => 'application/activity+json, application/ld+json']);
  80                 if (!$curlResult->isSuccess() || empty($curlResult->getBody())) {
  81                         return false;
  82                 }
  83
  84                 $content = json_decode($curlResult->getBody(), true);
  85
  86                 if (empty($content) || !is_array($content)) {
  87                         return false;
  88                 }
  89
  90                 return $content;
  91         }
  92
  93         private static function getAccountType($apcontact)
  94         {
  95                 $accounttype = -1;
  96
  97                 switch($apcontact['type']) {
  98                         case 'Person':
  99                                 $accounttype = User::ACCOUNT_TYPE_PERSON;
 100                                 break;
 101                         case 'Organization':
 102                                 $accounttype = User::ACCOUNT_TYPE_ORGANISATION;
 103                                 break;
 104                         case 'Service':
 105                                 $accounttype = User::ACCOUNT_TYPE_NEWS;
 106                                 break;
 107                         case 'Group':
 108                                 $accounttype = User::ACCOUNT_TYPE_COMMUNITY;
 109                                 break;
 110                         case 'Application':
 111                                 $accounttype = User::ACCOUNT_TYPE_RELAY;
 112                                 break;
 113                 }
 114
 115                 return $accounttype;
 116         }
 117
 118         /**
 119          * Fetches a profile from the given url into an array that is compatible to Probe::uri
 120          *
 121          * @param string  $url    profile url
 122          * @param boolean $update Update the profile
 123          * @return array
 124          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 125          * @throws \ImagickException
 126          */
 127         public static function probeProfile($url, $update = true)
 128         {
 129                 $apcontact = APContact::getByURL($url, $update);
 130                 if (empty($apcontact)) {
 131                         return false;
 132                 }
 133
 134                 $profile = ['network' => Protocol::ACTIVITYPUB];
 135                 $profile['nick'] = $apcontact['nick'];
 136                 $profile['name'] = $apcontact['name'];
 137                 $profile['guid'] = $apcontact['uuid'];
 138                 $profile['url'] = $apcontact['url'];
 139                 $profile['addr'] = $apcontact['addr'];
 140                 $profile['alias'] = $apcontact['alias'];
 141                 $profile['following'] = $apcontact['following'];
 142                 $profile['followers'] = $apcontact['followers'];
 143                 $profile['inbox'] = $apcontact['inbox'];
 144                 $profile['outbox'] = $apcontact['outbox'];
 145                 $profile['sharedinbox'] = $apcontact['sharedinbox'];
 146                 $profile['photo'] = $apcontact['photo'];
 147                 $profile['account-type'] = self::getAccountType($apcontact);
 148                 $profile['community'] = ($profile['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
 149                 // $profile['keywords']
 150                 // $profile['location']
 151                 $profile['about'] = $apcontact['about'];
 152                 $profile['batch'] = $apcontact['sharedinbox'];
 153                 $profile['notify'] = $apcontact['inbox'];
 154                 $profile['poll'] = $apcontact['outbox'];
 155                 $profile['pubkey'] = $apcontact['pubkey'];
 156                 $profile['baseurl'] = $apcontact['baseurl'];
 157
 158                 // Remove all "null" fields
 159                 foreach ($profile as $field => $content) {
 160                         if (is_null($content)) {
 161                                 unset($profile[$field]);
 162                         }
 163                 }
 164
 165                 return $profile;
 166         }
 167
 168         /**
 169          * Fetches activities from the outbox of a given profile and processes it
 170          *
 171          * @param string  $url
 172          * @param integer $uid User ID
 173          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 174          */
 175         public static function fetchOutbox($url, $uid)
 176         {
 177                 $data = self::fetchContent($url);
 178                 if (empty($data)) {
 179                         return;
 180                 }
 181
 182                 if (!empty($data['orderedItems'])) {
 183                         $items = $data['orderedItems'];
 184                 } elseif (!empty($data['first']['orderedItems'])) {
 185                         $items = $data['first']['orderedItems'];
 186                 } elseif (!empty($data['first'])) {
 187                         self::fetchOutbox($data['first'], $uid);
 188                         return;
 189                 } else {
 190                         $items = [];
 191                 }
 192
 193                 foreach ($items as $activity) {
 194                         $ldactivity = JsonLD::compact($activity);
 195                         ActivityPub\Receiver::processActivity($ldactivity, '', $uid, true);
 196                 }
 197         }
 198
 199         /**
 200          * Checks if the given contact url does support ActivityPub
 201          *
 202          * @param string  $url    profile url
 203          * @param boolean $update true = always update, false = never update, null = update when not found or outdated
 204          * @return boolean
 205          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 206          * @throws \ImagickException
 207          */
 208         public static function isSupportedByContactUrl($url, $update = null)
 209         {
 210                 return !empty(APContact::getByURL($url, $update));
 211         }
 212 }