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\Util\HTTPSignature;
  12
  13 /**
  14  * @brief ActivityPub Protocol class
  15  * The ActivityPub Protocol is a message exchange protocol defined by the W3C.
  16  * https://www.w3.org/TR/activitypub/
  17  * https://www.w3.org/TR/activitystreams-core/
  18  * https://www.w3.org/TR/activitystreams-vocabulary/
  19  *
  20  * https://blog.joinmastodon.org/2018/06/how-to-implement-a-basic-activitypub-server/
  21  * https://blog.joinmastodon.org/2018/07/how-to-make-friends-and-verify-requests/
  22  *
  23  * Digest: https://tools.ietf.org/html/rfc5843
  24  * https://tools.ietf.org/html/draft-cavage-http-signatures-10#ref-15
  25  *
  26  * Mastodon implementation of supported activities:
  27  * https://github.com/tootsuite/mastodon/blob/master/app/lib/activitypub/activity.rb#L26
  28  *
  29  * Funkwhale:
  30  * http://docs-funkwhale-funkwhale-549-music-federation-documentation.preview.funkwhale.audio/federation/index.html
  31  *
  32  * To-do:
  33  * - Polling the outboxes for missing content?
  34  *
  35  * Missing parts from DFRN:
  36  * - Public Forum
  37  * - Private Forum
  38  * - Relocation
  39  */
  40 class ActivityPub
  41 {
  42         const PUBLIC_COLLECTION = 'https://www.w3.org/ns/activitystreams#Public';
  43         const CONTEXT = ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1',
  44                 ['vcard' => 'http://www.w3.org/2006/vcard/ns#',
  45                 'dfrn' => 'http://purl.org/macgirvin/dfrn/1.0/',
  46                 'diaspora' => 'https://diasporafoundation.org/ns/',
  47                 'litepub' => 'http://litepub.social/ns#',
  48                 'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers',
  49                 'sensitive' => 'as:sensitive', 'Hashtag' => 'as:Hashtag',
  50                 'directMessage' => 'litepub:directMessage']];
  51         const ACCOUNT_TYPES = ['Person', 'Organization', 'Service', 'Group', 'Application'];
  52         /**
  53          * Checks if the web request is done for the AP protocol
  54          *
  55          * @return bool is it AP?
  56          */
  57         public static function isRequest()
  58         {
  59                 return stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/activity+json') ||
  60                         stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/ld+json');
  61         }
  62
  63         /**
  64          * Fetches ActivityPub content from the given url
  65          *
  66          * @param string  $url content url
  67          * @param integer $uid User ID for the signature
  68          * @return array
  69          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  70          */
  71         public static function fetchContent($url, $uid = 0)
  72         {
  73                 if (!empty($uid)) {
  74                         return HTTPSignature::fetch($url, $uid);
  75                 }
  76
  77                 $curlResult = Network::curl($url, false, $redirects, ['accept_content' => 'application/activity+json, application/ld+json']);
  78                 if (!$curlResult->isSuccess() || empty($curlResult->getBody())) {
  79                         return false;
  80                 }
  81
  82                 $content = json_decode($curlResult->getBody(), true);
  83
  84                 if (empty($content) || !is_array($content)) {
  85                         return false;
  86                 }
  87
  88                 return $content;
  89         }
  90
  91         /**
  92          * Fetches a profile from the given url into an array that is compatible to Probe::uri
  93          *
  94          * @param string  $url    profile url
  95          * @param boolean $update Update the profile
  96          * @return array
  97          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  98          * @throws \ImagickException
  99          */
 100         public static function probeProfile($url, $update = true)
 101         {
 102                 $apcontact = APContact::getByURL($url, $update);
 103                 if (empty($apcontact)) {
 104                         return false;
 105                 }
 106
 107                 $profile = ['network' => Protocol::ACTIVITYPUB];
 108                 $profile['nick'] = $apcontact['nick'];
 109                 $profile['name'] = $apcontact['name'];
 110                 $profile['guid'] = $apcontact['uuid'];
 111                 $profile['url'] = $apcontact['url'];
 112                 $profile['addr'] = $apcontact['addr'];
 113                 $profile['alias'] = $apcontact['alias'];
 114                 $profile['photo'] = $apcontact['photo'];
 115                 // $profile['community']
 116                 // $profile['keywords']
 117                 // $profile['location']
 118                 $profile['about'] = $apcontact['about'];
 119                 $profile['batch'] = $apcontact['sharedinbox'];
 120                 $profile['notify'] = $apcontact['inbox'];
 121                 $profile['poll'] = $apcontact['outbox'];
 122                 $profile['pubkey'] = $apcontact['pubkey'];
 123                 $profile['baseurl'] = $apcontact['baseurl'];
 124
 125                 // Remove all "null" fields
 126                 foreach ($profile as $field => $content) {
 127                         if (is_null($content)) {
 128                                 unset($profile[$field]);
 129                         }
 130                 }
 131
 132                 return $profile;
 133         }
 134
 135         /**
 136          * Fetches activities from the outbox of a given profile and processes it
 137          *
 138          * @param string  $url
 139          * @param integer $uid User ID
 140          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 141          */
 142         public static function fetchOutbox($url, $uid)
 143         {
 144                 $data = self::fetchContent($url);
 145                 if (empty($data)) {
 146                         return;
 147                 }
 148
 149                 if (!empty($data['orderedItems'])) {
 150                         $items = $data['orderedItems'];
 151                 } elseif (!empty($data['first']['orderedItems'])) {
 152                         $items = $data['first']['orderedItems'];
 153                 } elseif (!empty($data['first'])) {
 154                         self::fetchOutbox($data['first'], $uid);
 155                         return;
 156                 } else {
 157                         $items = [];
 158                 }
 159
 160                 foreach ($items as $activity) {
 161                         $ldactivity = JsonLD::compact($activity);
 162                         ActivityPub\Receiver::processActivity($ldactivity, '', $uid, true);
 163                 }
 164         }
 165 }