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  * @brief ActivityPub Protocol class
  16  * The ActivityPub Protocol is a message exchange protocol defined by the W3C.
  17  * https://www.w3.org/TR/activitypub/
  18  * https://www.w3.org/TR/activitystreams-core/
  19  * https://www.w3.org/TR/activitystreams-vocabulary/
  20  *
  21  * https://blog.joinmastodon.org/2018/06/how-to-implement-a-basic-activitypub-server/
  22  * https://blog.joinmastodon.org/2018/07/how-to-make-friends-and-verify-requests/
  23  *
  24  * Digest: https://tools.ietf.org/html/rfc5843
  25  * https://tools.ietf.org/html/draft-cavage-http-signatures-10#ref-15
  26  *
  27  * Mastodon implementation of supported activities:
  28  * https://github.com/tootsuite/mastodon/blob/master/app/lib/activitypub/activity.rb#L26
  29  *
  30  * Funkwhale:
  31  * http://docs-funkwhale-funkwhale-549-music-federation-documentation.preview.funkwhale.audio/federation/index.html
  32  *
  33  * To-do:
  34  * - Polling the outboxes for missing content?
  35  *
  36  * Missing parts from DFRN:
  37  * - Public Forum
  38  * - Private Forum
  39  * - Relocation
  40  */
  41 class ActivityPub
  42 {
  43         const PUBLIC_COLLECTION = 'https://www.w3.org/ns/activitystreams#Public';
  44         const CONTEXT = ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1',
  45                 ['vcard' => 'http://www.w3.org/2006/vcard/ns#',
  46                 'dfrn' => 'http://purl.org/macgirvin/dfrn/1.0/',
  47                 'diaspora' => 'https://diasporafoundation.org/ns/',
  48                 'litepub' => 'http://litepub.social/ns#',
  49                 'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers',
  50                 'sensitive' => 'as:sensitive', 'Hashtag' => 'as:Hashtag',
  51                 'directMessage' => 'litepub:directMessage']];
  52         const ACCOUNT_TYPES = ['Person', 'Organization', 'Service', 'Group', 'Application'];
  53         /**
  54          * Checks if the web request is done for the AP protocol
  55          *
  56          * @return bool is it AP?
  57          */
  58         public static function isRequest()
  59         {
  60                 return stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/activity+json') ||
  61                         stristr(defaults($_SERVER, 'HTTP_ACCEPT', ''), 'application/ld+json');
  62         }
  63
  64         /**
  65          * Fetches ActivityPub content from the given url
  66          *
  67          * @param string  $url content url
  68          * @param integer $uid User ID for the signature
  69          * @return array
  70          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  71          */
  72         public static function fetchContent($url, $uid = 0)
  73         {
  74                 if (!empty($uid)) {
  75                         return HTTPSignature::fetch($url, $uid);
  76                 }
  77
  78                 $curlResult = Network::curl($url, false, ['accept_content' => 'application/activity+json, application/ld+json']);
  79                 if (!$curlResult->isSuccess() || empty($curlResult->getBody())) {
  80                         return false;
  81                 }
  82
  83                 $content = json_decode($curlResult->getBody(), true);
  84
  85                 if (empty($content) || !is_array($content)) {
  86                         return false;
  87                 }
  88
  89                 return $content;
  90         }
  91
  92         private static function getAccountType($apcontact)
  93         {
  94                 $accounttype = -1;
  95
  96                 switch($apcontact['type']) {
  97                         case 'Person':
  98                                 $accounttype = User::ACCOUNT_TYPE_PERSON;
  99                                 break;
 100                         case 'Organization':
 101                                 $accounttype = User::ACCOUNT_TYPE_ORGANISATION;
 102                                 break;
 103                         case 'Service':
 104                                 $accounttype = User::ACCOUNT_TYPE_NEWS;
 105                                 break;
 106                         case 'Group':
 107                                 $accounttype = User::ACCOUNT_TYPE_COMMUNITY;
 108                                 break;
 109                         case 'Application':
 110                                 $accounttype = User::ACCOUNT_TYPE_RELAY;
 111                                 break;
 112                 }
 113
 114                 return $accounttype;
 115         }
 116
 117         /**
 118          * Fetches a profile from the given url into an array that is compatible to Probe::uri
 119          *
 120          * @param string  $url    profile url
 121          * @param boolean $update Update the profile
 122          * @return array
 123          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 124          * @throws \ImagickException
 125          */
 126         public static function probeProfile($url, $update = true)
 127         {
 128                 $apcontact = APContact::getByURL($url, $update);
 129                 if (empty($apcontact)) {
 130                         return false;
 131                 }
 132
 133                 $profile = ['network' => Protocol::ACTIVITYPUB];
 134                 $profile['nick'] = $apcontact['nick'];
 135                 $profile['name'] = $apcontact['name'];
 136                 $profile['guid'] = $apcontact['uuid'];
 137                 $profile['url'] = $apcontact['url'];
 138                 $profile['addr'] = $apcontact['addr'];
 139                 $profile['alias'] = $apcontact['alias'];
 140                 $profile['following'] = $apcontact['following'];
 141                 $profile['followers'] = $apcontact['followers'];
 142                 $profile['inbox'] = $apcontact['inbox'];
 143                 $profile['outbox'] = $apcontact['outbox'];
 144                 $profile['sharedinbox'] = $apcontact['sharedinbox'];
 145                 $profile['photo'] = $apcontact['photo'];
 146                 $profile['account-type'] = self::getAccountType($apcontact);
 147                 $profile['community'] = ($profile['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
 148                 // $profile['keywords']
 149                 // $profile['location']
 150                 $profile['about'] = $apcontact['about'];
 151                 $profile['batch'] = $apcontact['sharedinbox'];
 152                 $profile['notify'] = $apcontact['inbox'];
 153                 $profile['poll'] = $apcontact['outbox'];
 154                 $profile['pubkey'] = $apcontact['pubkey'];
 155                 $profile['baseurl'] = $apcontact['baseurl'];
 156
 157                 // Remove all "null" fields
 158                 foreach ($profile as $field => $content) {
 159                         if (is_null($content)) {
 160                                 unset($profile[$field]);
 161                         }
 162                 }
 163
 164                 return $profile;
 165         }
 166
 167         /**
 168          * Fetches activities from the outbox of a given profile and processes it
 169          *
 170          * @param string  $url
 171          * @param integer $uid User ID
 172          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 173          */
 174         public static function fetchOutbox($url, $uid)
 175         {
 176                 $data = self::fetchContent($url);
 177                 if (empty($data)) {
 178                         return;
 179                 }
 180
 181                 if (!empty($data['orderedItems'])) {
 182                         $items = $data['orderedItems'];
 183                 } elseif (!empty($data['first']['orderedItems'])) {
 184                         $items = $data['first']['orderedItems'];
 185                 } elseif (!empty($data['first'])) {
 186                         self::fetchOutbox($data['first'], $uid);
 187                         return;
 188                 } else {
 189                         $items = [];
 190                 }
 191
 192                 foreach ($items as $activity) {
 193                         $ldactivity = JsonLD::compact($activity);
 194                         ActivityPub\Receiver::processActivity($ldactivity, '', $uid, true);
 195                 }
 196         }
 197
 198         /**
 199          * Checks if the given contact url does support ActivityPub
 200          *
 201          * @param string  $url    profile url
 202          * @param boolean $update Update the profile
 203          * @return boolean
 204          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 205          * @throws \ImagickException
 206          */
 207         public static function isSupportedByContactUrl($url, $update = null)
 208         {
 209                 return !empty(APContact::getByURL($url, $update));
 210         }
 211 }