Proper AP Notices (fixed #46)

Explorer now works both for local and remote URIs
Fixed various serious errors (most of them in Explorer
and some in AP Profiles)

ActivityPubPlugin.php

@@ -34,6 +34,9 @@ require_once __DIR__ . DIRECTORY_SEPARATOR . "utils" . DIRECTORY_SEPARATOR . "di
 require_once __DIR__ . DIRECTORY_SEPARATOR . "utils" . DIRECTORY_SEPARATOR . "explorer.php";
 require_once __DIR__ . DIRECTORY_SEPARATOR . "utils" . DIRECTORY_SEPARATOR . "postman.php";
 
+// So that this isn't hardcoded everywhere
+define('ACTIVITYPUB_BASE_INSTANCE_URI', common_root_url()."index.php/user/");
+
 /**
  * @category  Plugin
  * @package   GNUsocial
@@ -54,7 +57,7 @@ class ActivityPubPlugin extends Plugin
     public static function actor_uri($profile)
     {
         if ($profile->isLocal()) {
-            return common_root_url()."index.php/user/".$profile->getID();
+            return ACTIVITYPUB_BASE_INSTANCE_URI.$profile->getID();
         } else {
             return $profile->getUri();
         }
@@ -74,46 +77,30 @@ class ActivityPubPlugin extends Plugin
     }
 
     /**
-     * Get remote user's ActivityPub_profile via a identifier
+     * Returns a notice from its URL since GNU Social doesn't provide
+     * this functionality
      *
-     * @author GNU Social
      * @author Diogo Cordeiro <diogo@fc.up.pt>
-     * @param string $arg A remote user identifier
+     * @param string $url Notice's URL
-     * @return Activitypub_profile|null Valid profile in success | null otherwise
+     * @return Notice The Notice object
+     * @throws Exception This function or provides a Notice or fails with exception
      */
-    public static function pull_remote_profile($arg)
+    public static function get_local_notice_from_url($url)
     {
-        if (preg_match('!^((?:\w+\.)*\w+@(?:\w+\.)*\w+(?:\w+\-\w+)*\.\w+)$!', $arg)) {
-            // webfinger lookup
         try {
-                return Activitypub_profile::ensure_web_finger($arg);
+            return Notice::getByUri($data->object->inReplyTo);
         } catch (Exception $e) {
-                common_log(LOG_ERR, 'Webfinger lookup failed for ' .
-                                                $arg . ': ' . $e->getMessage());
-            }
-        }
-
-        // Look for profile URLs, with or without scheme:
-        $urls = array();
-        if (preg_match('!^https?://((?:\w+\.)*\w+(?:\w+\-\w+)*\.\w+(?:/\w+)+)$!', $arg)) {
-            $urls[] = $arg;
-        }
-        if (preg_match('!^((?:\w+\.)*\w+(?:\w+\-\w+)*\.\w+(?:/\w+)+)$!', $arg)) {
-            $schemes = array('http', 'https');
-            foreach ($schemes as $scheme) {
-                $urls[] = "$scheme://$arg";
-            }
-        }
-
-        foreach ($urls as $url) {
             try {
-                return Activitypub_profile::get_from_uri($url);
+                $candidate = Notice::getByID(intval(substr($url, strlen(common_local_url('shownotice', ['notice' => ''])))));
+                if ($candidate->getUrl() == $url) {
+                    return $candidate;
+                } else {
+                    throw new Exception("Notice not found.");
+                }
             } catch (Exception $e) {
-                common_log(LOG_ERR, 'Profile lookup failed for ' .
+                throw new Exception("Notice not found.");
-                                                $arg . ': ' . $e->getMessage());
             }
         }
-        return null;
     }
 
     /**
@@ -234,6 +221,49 @@ class ActivityPubPlugin extends Plugin
      *                   WebFinger Events                   *
      ********************************************************/
 
+    /**
+     * Get remote user's ActivityPub_profile via a identifier
+     *
+     * @author GNU Social
+     * @author Diogo Cordeiro <diogo@fc.up.pt>
+     * @param string $arg A remote user identifier
+     * @return Activitypub_profile|null Valid profile in success | null otherwise
+     */
+    public static function pull_remote_profile($arg)
+    {
+        if (preg_match('!^((?:\w+\.)*\w+@(?:\w+\.)*\w+(?:\w+\-\w+)*\.\w+)$!', $arg)) {
+            // webfinger lookup
+            try {
+                return Activitypub_profile::ensure_web_finger($arg);
+            } catch (Exception $e) {
+                common_log(LOG_ERR, 'Webfinger lookup failed for ' .
+                                                $arg . ': ' . $e->getMessage());
+            }
+        }
+
+        // Look for profile URLs, with or without scheme:
+        $urls = array();
+        if (preg_match('!^https?://((?:\w+\.)*\w+(?:\w+\-\w+)*\.\w+(?:/\w+)+)$!', $arg)) {
+            $urls[] = $arg;
+        }
+        if (preg_match('!^((?:\w+\.)*\w+(?:\w+\-\w+)*\.\w+(?:/\w+)+)$!', $arg)) {
+            $schemes = array('http', 'https');
+            foreach ($schemes as $scheme) {
+                $urls[] = "$scheme://$arg";
+            }
+        }
+
+        foreach ($urls as $url) {
+            try {
+                return Activitypub_profile::fromUri($url);
+            } catch (Exception $e) {
+                common_log(LOG_ERR, 'Profile lookup failed for ' .
+                                                $arg . ': ' . $e->getMessage());
+            }
+        }
+        return null;
+    }
+
     /**
     * Webfinger matches: @user@example.com or even @user--one.george_orwell@1984.biz
     *
@@ -357,7 +387,7 @@ class ActivityPubPlugin extends Plugin
                 $url = "$scheme://$target";
                 $this->log(LOG_INFO, "Checking profile address '$url'");
                 try {
-                    $aprofile = Activitypub_profile::get_from_uri($url);
+                    $aprofile = Activitypub_profile::fromUri($url);
                     $profile = $aprofile->local_profile();
                     $displayName = !empty($profile->nickname) && mb_strlen($profile->nickname) < mb_strlen($target) ?
                                         $profile->nickname : $target;
@@ -432,7 +462,7 @@ class ActivityPubPlugin extends Plugin
     {
         $aprofile = Activitypub_profile::getKV('profile_id', $profile->id);
         if ($aprofile instanceof Activitypub_profile) {
-            $uri = $aprofile->get_uri();
+            $uri = $aprofile->getUri();
             return false;
         }
         return true;
@@ -449,27 +479,9 @@ class ActivityPubPlugin extends Plugin
      */
     public function onStartGetProfileFromURI($uri, &$profile)
     {
-        // Don't want to do Web-based discovery on our own server,
-        // so we check locally first. This duplicates the functionality
-        // in the Profile class, since the plugin always runs before
-        // that local lookup, but since we return false it won't run double.
-
-        $user = User::getKV('uri', $uri);
-        if ($user instanceof User) {
-            $profile = $user->getProfile();
-            return false;
-        } else {
-            $group = User_group::getKV('uri', $uri);
-            if ($group instanceof User_group) {
-                $profile = $group->getProfile();
-                return false;
-            }
-        }
-
-        // Now, check remotely
         try {
-            $aprofile = Activitypub_profile::get_from_uri($uri);
+            $explorer = new Activitypub_explorer();
-            $profile = $aprofile->local_profile();
+            $profile = $explorer->lookup($uri)[0];
             return false;
         } catch (Exception $e) {
             return true; // It's not an ActivityPub profile as far as we know, continue event handling

actions/apactorfollowers.php

@@ -58,6 +58,10 @@ class apActorFollowersAction extends ManagedAction
             ActivityPubReturn::error('Invalid Actor URI.', 404);
         }
 
+        if (!$profile->isLocal()) {
+            ActivityPubReturn::error("This is not a local user.");
+        }
+
         if (!isset($_GET["page"])) {
             $page = 1;
         } else {
@@ -93,7 +97,7 @@ class apActorFollowersAction extends ManagedAction
         /* Get followers' URLs */
         $subs = array();
         while ($sub->fetch()) {
-            $subs[] = $sub->profileurl;
+            $subs[] = ActivityPubPlugin::actor_uri($sub);
         }
 
         $res = [

actions/apactorfollowing.php

@@ -58,6 +58,10 @@ class apActorFollowingAction extends ManagedAction
             ActivityPubReturn::error('Invalid Actor URI.', 404);
         }
 
+        if (!$profile->isLocal()) {
+            ActivityPubReturn::error("This is not a local user.");
+        }
+
         if (!isset($_GET["page"])) {
             $page = 1;
         } else {
@@ -93,7 +97,7 @@ class apActorFollowingAction extends ManagedAction
         /* Get followed' URLs */
         $subs = array();
         while ($sub->fetch()) {
-            $subs[] = $sub->profileurl;
+            $subs[] = ActivityPubPlugin::actor_uri($sub);
         }
 
         $res = [

actions/apactorinbox.php

@@ -57,6 +57,10 @@ class apActorInboxAction extends ManagedAction
             ActivityPubReturn::error('Invalid Actor URI.', 404);
         }
 
+        if (!$profile->isLocal()) {
+            ActivityPubReturn::error("This is not a local user.");
+        }
+
         if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
             ActivityPubReturn::error("C2S not implemented just yet.");
         }

actions/apactorliked.php

@@ -58,6 +58,10 @@ class apActorLikedAction extends ManagedAction
             ActivityPubReturn::error('Invalid Actor URI.', 404);
         }
 
+        if (!$profile->isLocal()) {
+            ActivityPubReturn::error("This is not a local user.");
+        }
+
         $limit    = intval($this->trimmed('limit'));
         $since_id = intval($this->trimmed('since_id'));
         $max_id   = intval($this->trimmed('max_id'));

actions/inbox/Announce.php

@@ -30,7 +30,7 @@ if (!defined('GNUSOCIAL')) {
 }
 
 try {
-    Notice::getByUri($data->object->id)->repeat($actor_profile, "ActivityPub");
+    ActivityPubPlugin::get_local_notice_from_url($data->object->id)->repeat($actor_profile, "ActivityPub");
     ActivityPubReturn::answer("Notice repeated successfully.");
 } catch (Exception $e) {
     ActivityPubReturn::error($e->getMessage(), 403);

actions/inbox/Create.php

@@ -32,8 +32,10 @@ if (!defined('GNUSOCIAL')) {
 $valid_object_types = array("Note");
 
 // Validate data
-if (!isset($data->id)) {
+if (!isset($data->object->id)) {
-    ActivityPubReturn::error("Id not specified.");
+    ActivityPubReturn::error("Object ID not specified.");
+} elseif (!filter_var($data->object->id, FILTER_VALIDATE_URL)) {
+    ActivityPubReturn::error("Invalid Object ID.");
 }
 if (!(isset($data->object->type) && in_array($data->object->type, $valid_object_types))) {
     ActivityPubReturn::error("Invalid Object type.");
@@ -60,19 +62,19 @@ $act->actor = $actor_profile->asActivityObject();
 $act->context = new ActivityContext();
 
 // Is this a reply?
-if (isset($data->object->reply_to)) {
+if (isset($data->object->inReplyTo)) {
     try {
-        $reply_to = Notice::getByUri($data->object->reply_to);
+        $inReplyTo = ActivityPubPlugin::get_local_notice_from_url($data->object->inReplyTo);
     } catch (Exception $e) {
-        ActivityPubReturn::error("Invalid Object reply_to value.");
+        ActivityPubReturn::error("Invalid Object inReplyTo value.");
     }
-    $act->context->replyToID  = $reply_to->getUri();
+    $act->context->replyToID  = $inReplyTo->getUri();
-    $act->context->replyToUrl = $reply_to->getUrl();
+    $act->context->replyToUrl = $inReplyTo->getUrl();
 } else {
-    $reply_to = null;
+    $inReplyTo = null;
 }
 
-$act->context->attention = common_get_attentions($content, $actor_profile, $reply_to);
+$act->context->attention = common_get_attentions($content, $actor_profile, $inReplyTo);
 
 $discovery = new Activitypub_explorer;
 if ($to_profiles == "https://www.w3.org/ns/activitystreams#Public") {
@@ -86,22 +88,43 @@ if (is_array($data->object->to)) {
         try {
             $to_profiles = array_merge($to_profiles, $discovery->lookup($to_url));
         } catch (Exception $e) {
-            // XXX: Invalid actor found, not sure how we handle those
+            // Invalid actor found, just let it go.
         }
     }
 } elseif (empty($data->object->to) || in_array($data->object->to, $public_to)) {
     // No need to do anything else at this point, let's just break out the if
 } else {
     try {
-        $to_profiles[]= $discovery->lookup($data->object->to);
+        $to_profiles = array_merge($to_profiles, $discovery->lookup($data->object->to));
     } catch (Exception $e) {
-        ActivityPubReturn::error("Invalid Actor.", 404);
+        // Invalid actor found, just let it go.
     }
 }
+// Generate Cc objects
+if (isset($data->object->cc) && is_array($data->object->cc)) {
+    // Remove duplicates from Cc actors set
+    array_unique($data->object->to);
+    foreach ($data->object->cc as $cc_url) {
+        try {
+            $to_profiles = array_merge($to_profiles, $discovery->lookup($cc_url));
+        } catch (Exception $e) {
+            // Invalid actor found, just let it go.
+        }
+    }
+} elseif (empty($data->object->cc) || in_array($data->object->cc, $public_to)) {
+    // No need to do anything else at this point, let's just break out the if
+} else {
+    try {
+        $to_profiles = array_merge($to_profiles, $discovery->lookup($data->object->cc));
+    } catch (Exception $e) {
+        // Invalid actor found, just let it go.
+    }
+}
+
 unset($discovery);
 
-foreach ($to_profiles as $to) {
+foreach ($to_profiles as $tp) {
-    $act->context->attention[ActivityPubPlugin::actor_uri($to)] = "http://activitystrea.ms/schema/1.0/person";
+    $act->context->attention[ActivityPubPlugin::actor_uri($tp)] = "http://activitystrea.ms/schema/1.0/person";
 }
 
 // Reject notice if it is too long (without the HTML)
@@ -116,7 +139,7 @@ ToSelector::fillActivity($this, $act, $options);
 
 $actobj = new ActivityObject();
 $actobj->type = ActivityObject::NOTE;
-$actobj->content = common_render_content($content, $actor_profile, $reply_to);
+$actobj->content = common_render_content($content, $actor_profile, $inReplyTo);
 
 // Finally add the activity object to our activity
 $act->objects[] = $actobj;

actions/inbox/Delete.php

@@ -30,7 +30,7 @@ if (!defined('GNUSOCIAL')) {
 }
 
 try {
-    $notice = Notice::getByUri($data->object->id);
+    $notice = ActivityPubPlugin::get_local_notice_from_url($data->object->id);
     $notice_to_array = Activitypub_notice::notice_to_array($notice);
     $notice->deleteAs($actor_profile);
     ActivityPubReturn::answer(Activitypub_delete::delete_to_array($notice_to_array));

actions/inbox/Like.php

@@ -34,8 +34,13 @@ if (!isset($data->object->id)) {
 }
 
 try {
-    Fave::addNew($actor_profile, Notice::getByUri($data->object->id));
+    try {
-    ActivityPubReturn::answer(Activitypub_like::like_to_array(Activitypub_notice::notice_to_array($data->actor, json_decode($data->object))));
+        $object_notice = ActivityPubPlugin::get_local_notice_from_url($data->object->id);
+    } catch (Exception $e) {
+        ActivityPubReturn::error("Invalid Object ID value.");
+    }
+    Fave::addNew($actor_profile, $object_notice);
+    ActivityPubReturn::answer(Activitypub_like::like_to_array($data->actor, Activitypub_notice::notice_to_array($object_notice)));
 } catch (Exception $e) {
     ActivityPubReturn::error($e->getMessage(), 403);
 }

actions/inbox/Undo.php

@@ -41,7 +41,7 @@ case "Like":
             if (!isset($data->object->object->id)) {
                 ActivityPubReturn::error("Notice ID was not specified.");
             }
-            Fave::removeEntry($actor_profile, Notice::getByUri($data->object->object->id));
+            Fave::removeEntry($actor_profile, ActivityPubPlugin::get_local_notice_from_url($data->object->object->id));
             // Notice disfavorited successfully.
             ActivityPubReturn::answer(
                     Activitypub_undo::undo_to_array(

classes/Activitypub_notice.php

@@ -34,7 +34,6 @@ if (!defined('GNUSOCIAL')) {
  *
  * @category  Plugin
  * @package   GNUsocial
- * @author    Daniel Supernault <danielsupernault@gmail.com>
  * @author    Diogo Cordeiro <diogo@fc.up.pt>
  * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
  * @link      http://www.gnu.org/software/social/
@@ -44,13 +43,13 @@ class Activitypub_notice extends Managed_DataObject
     /**
      * Generates a pretty notice from a Notice object
      *
-     * @author Daniel Supernault <danielsupernault@gmail.com>
      * @author Diogo Cordeiro <diogo@fc.up.pt>
      * @param Notice $notice
      * @return pretty array to be used in a response
      */
     public static function notice_to_array($notice)
     {
+        $profile = $notice->getProfile();
         $attachments = array();
         foreach ($notice->attachments() as $attachment) {
             $attachments[] = Activitypub_attachment::attachment_to_array($attachment);
@@ -63,7 +62,7 @@ class Activitypub_notice extends Managed_DataObject
             }
         }
 
-        $to = array();
+        $to = [];
         foreach ($notice->getAttentionProfiles() as $to_profile) {
             $to[] = $to_profile->getUri();
         }
@@ -72,16 +71,18 @@ class Activitypub_notice extends Managed_DataObject
         }
 
         $item = [
-                        'id'           => $notice->getUri(),
+                        'id'               => $notice->getUrl(),
                         'type'             => 'Note',
-                        'actor'        => $notice->getProfile()->getUrl(),
+                        'inReplyTo'        => empty($notice->reply_to) ? null : Notice::getById($notice->reply_to)->getUrl(),
                         'published'        => $notice->getCreated(),
-                        'to'           => $to,
-                        'content'      => $notice->getContent(),
                         'url'              => $notice->getUrl(),
-                        'reply_to'     => empty($notice->reply_to) ? null : Notice::getById($notice->reply_to)->getUri(),
+                        'atributedTo'      => ActivityPubPlugin::actor_uri($profile),
-                        'is_local'     => $notice->isLocal(),
+                        'to'               => $to,
+                        'atomUri'          => $notice->getUrl(),
+                        'inReplyToAtomUri' => empty($notice->reply_to) ? null : Notice::getById($notice->reply_to)->getUrl(),
                         'conversation'     => $notice->getConversationUrl(),
+                        'content'          => $notice->getContent(),
+                        'is_local'         => $notice->isLocal(),
                         'attachment'       => $attachments,
                         'tag'              => $tags
                 ];

classes/Activitypub_profile.php

@@ -41,6 +41,18 @@ if (!defined('GNUSOCIAL')) {
 class Activitypub_profile extends Managed_DataObject
 {
     public $__table = 'Activitypub_profile';
+    public $uri;                             // text()   not_null
+    public $profile_id;                      // int(4)  primary_key not_null
+    public $inboxuri;                        // text()   not_null
+    public $sharedInboxuri;                  // text()
+    public $nickname;                        // varchar(64)  multiple_key not_null
+    public $fullname;                        // text()
+    public $profileurl;                      // text()
+    public $homepage;                        // text()
+    public $bio;                             // text()  multiple_key
+    public $location;                        // text()
+    public $created;                         // datetime()   not_null
+    public $modified;                        // timestamp()   not_null default_CURRENT_TIMESTAMP
 
     /**
      * Return table definition for Schema setup and DB_DataObject usage.
@@ -108,7 +120,7 @@ class Activitypub_profile extends Managed_DataObject
             'liked'             => common_local_url("apActorLiked", array("id" => $id)),
             'inbox'             => common_local_url("apActorInbox", array("id" => $id)),
             'preferredUsername' => $profile->getNickname(),
-            'name'              => $profile->getFullname(),
+            'name'              => $profile->getBestName(),
             'summary'           => ($desc = $profile->getDescription()) == null ? "" : $desc,
             'url'               => $profile->getUrl(),
             'manuallyApprovesFollowers' => false,
@@ -280,11 +292,33 @@ class Activitypub_profile extends Managed_DataObject
      * @author Diogo Cordeiro <diogo@fc.up.pt>
      * @return string URI
      */
-    public function get_uri()
+    public function getUri()
     {
         return $this->uri;
     }
 
+    /**
+     * Getter for url property
+     *
+     * @author Diogo Cordeiro <diogo@fc.up.pt>
+     * @return string URL
+     */
+    public function getUrl()
+    {
+        return $this->getUri();
+    }
+
+    /**
+     * Getter for id property
+     *
+     * @author Diogo Cordeiro <diogo@fc.up.pt>
+     * @return int32
+     */
+    public function getID()
+    {
+        return $this->profile_id;
+    }
+
     /**
      * Ensures a valid Activitypub_profile when provided with a valid URI.
      *
@@ -293,7 +327,7 @@ class Activitypub_profile extends Managed_DataObject
      * @return Activitypub_profile
      * @throws Exception if it isn't possible to return an Activitypub_profile
      */
-    public static function get_from_uri($url)
+    public static function fromUri($url)
     {
         $explorer = new Activitypub_explorer();
         $profiles_found = $explorer->lookup($url);
@@ -331,7 +365,7 @@ class Activitypub_profile extends Managed_DataObject
                 throw new Exception(_m('Not a valid webfinger address (via cache).'));
             }
             try {
-                return self::get_from_uri($uri);
+                return self::fromUri($uri);
             } catch (Exception $e) {
                 common_log(LOG_ERR, sprintf(__METHOD__ . ': Webfinger address cache inconsistent with database, did not find Activitypub_profile uri==%s', $uri));
                 self::cacheSet(sprintf('activitypub_profile:webfinger:%s', $addr), false);
@@ -372,8 +406,8 @@ class Activitypub_profile extends Managed_DataObject
             $profileUrl = $hints['profileurl'];
             try {
                 common_log(LOG_INFO, "Discovery on acct:$addr with profile URL $profileUrl");
-                $aprofile = self::get_from_uri($hints['profileurl']);
+                $aprofile = self::fromUri($hints['profileurl']);
-                self::cacheSet(sprintf('activitypub_profile:webfinger:%s', $addr), $aprofile->get_uri());
+                self::cacheSet(sprintf('activitypub_profile:webfinger:%s', $addr), $aprofile->getUri());
                 return $aprofile;
             } catch (Exception $e) {
                 common_log(LOG_WARNING, "Failed creating profile from profile URL '$profileUrl': " . $e->getMessage());

tests/Unit/ActivitypubProfileTest.php

@@ -49,11 +49,17 @@ class ProfileObjectTest extends TestCase
         /* Test get_inbox() */
         $this->assertTrue($aprofile->sharedInboxuri == $aprofile->get_inbox());
 
-        /* Test get_uri() */
+        /* Test getUri() */
-        $this->assertTrue($aprofile->uri == $aprofile->get_uri());
+        $this->assertTrue($aprofile->uri == $aprofile->getUri());
 
-        /* Test get_from_uri() */
+        /* Test getUrl() */
-        $this->assertTrue($this->compare_aprofiles($aprofile, \Activitypub_profile::get_from_uri($aprofile->uri)));
+        $this->assertTrue($profile->getUrl() == $aprofile->getUrl());
+
+        /* Test getID() */
+        $this->assertTrue($profile->getID() == $aprofile->getID());
+
+        /* Test fromUri() */
+        $this->assertTrue($this->compare_aprofiles($aprofile, \Activitypub_profile::fromUri($aprofile->uri)));
 
         /* Remove Remote User Test 1 */
         $old_id = $profile->getID();
@@ -124,20 +130,28 @@ class ProfileObjectTest extends TestCase
 
     private function compare_aprofiles(\Activitypub_profile $a, \Activitypub_profile $b)
     {
-        if (($av = $a->get_uri()) != ($bv = $b->get_uri())) {
+        if (($av = $a->getUri()) != ($bv = $b->getUri())) {
             throw new Exception('Compare AProfiles 1 Fail: $a: '.$av.' is different from $b: '.$bv);
         }
 
-        if (($av = $a->profile_id) != ($bv = $b->profile_id)) {
+        if (($av = $a->getUrl()) != ($bv = $b->getUrl())) {
             throw new Exception('Compare AProfiles 2 Fail: $a: '.$av.' is different from $b: '.$bv);
         }
 
-        if (($av = $a->inboxuri) != ($bv = $b->inboxuri)) {
+        if (($av = $a->getID()) != ($bv = $b->getID())) {
             throw new Exception('Compare AProfiles 3 Fail: $a: '.$av.' is different from $b: '.$bv);
         }
 
+        if (($av = $a->profile_id) != ($bv = $b->profile_id)) {
+            throw new Exception('Compare AProfiles 4 Fail: $a: '.$av.' is different from $b: '.$bv);
+        }
+
+        if (($av = $a->inboxuri) != ($bv = $b->inboxuri)) {
+            throw new Exception('Compare AProfiles 5 Fail: $a: '.$av.' is different from $b: '.$bv);
+        }
+
         if (($av = $a->sharedInboxuri) != ($bv = $b->sharedInboxuri)) {
-            throw new Exception('Compare AProfiles 1 Fail: $a: '.$av.' is different from $b: '.$bv);
+            throw new Exception('Compare AProfiles 6 Fail: $a: '.$av.' is different from $b: '.$bv);
         }
 
         return true;

utils/explorer.php

@@ -32,7 +32,7 @@ if (!defined('GNUSOCIAL')) {
 /**
  * ActivityPub's own Explorer
  *
- * Allows to discovery new (or the same) ActivityPub profiles
+ * Allows to discovery new (or the same) Profiles (both local or remote)
  *
  * @category  Plugin
  * @package   GNUsocial
@@ -55,6 +55,7 @@ class Activitypub_explorer
      */
     public function lookup($url)
     {
+        common_debug("Explorer started now looking for ".$url);
         $this->discovered_actor_profiles = array();
 
         return $this->_lookup($url);
@@ -95,9 +96,6 @@ class Activitypub_explorer
         $headers[] = 'Accept: application/ld+json; profile="https://www.w3.org/ns/activitystreams"';
         $headers[] = 'User-Agent: GNUSocialBot v0.1 - https://gnu.io/social';
         $response  = $client->get($url, $headers);
-        if (!$response->isOk()) {
-            throw new Exception("Invalid Actor URL.");
-        }
         $res = json_decode($response->getBody(), JSON_UNESCAPED_SLASHES);
         if (self::validate_remote_response($res)) {
             $this->temp_res = $res;
@@ -108,7 +106,7 @@ class Activitypub_explorer
     }
 
     /**
-     * Get a local user profiles from its URL and joins it on
+     * Get a local user profile from its URL and joins it on
      * $this->discovered_actor_profiles
      *
      * @author Diogo Cordeiro <diogo@fc.up.pt>
@@ -117,6 +115,11 @@ class Activitypub_explorer
      */
     private function grab_local_user($uri, $online = false)
     {
+        if ($online) {
+            common_debug("Explorer is searching locally for ".$uri. " online.");
+        } else {
+            common_debug("Explorer is searching locally for ".$uri. " offline.");
+        }
         // Ensure proper remote URI
         // If an exception occurs here it's better to just leave everything
         // break than to continue processing
@@ -126,14 +129,31 @@ class Activitypub_explorer
 
         // Try standard ActivityPub route
         // Is this a known filthy little mudblood?
-        $aprofile = Activitypub_profile::getKV("uri", $uri);
+        $aprofile = self::get_aprofile_by_url($uri);
         if ($aprofile instanceof Activitypub_profile) {
             $profile = $aprofile->local_profile();
+            common_debug("Explorer found a local Aprofile for ".$uri);
+            // We found something!
+            $this->discovered_actor_profiles[]= $profile;
+            unset($this->temp_res); // IMPORTANT to avoid _dangerous_ noise in the Explorer system
+            return true;
+        } else {
+            common_debug("Explorer didn't find a local Aprofile for ".$uri);
+            // Well, maybe it is a pure blood?
+            // Iff, we are in the same instance:
+            $ACTIVITYPUB_BASE_INSTANCE_URI_length = strlen(ACTIVITYPUB_BASE_INSTANCE_URI);
+            if (substr($uri, 0, $ACTIVITYPUB_BASE_INSTANCE_URI_length) == ACTIVITYPUB_BASE_INSTANCE_URI) {
+                try {
+                    $profile = Profile::getByID(intval(substr($uri, $ACTIVITYPUB_BASE_INSTANCE_URI_length)));
 
                     // We found something!
                     $this->discovered_actor_profiles[]= $profile;
                     unset($this->temp_res); // IMPORTANT to avoid _dangerous_ noise in the Explorer system
                     return true;
+                } catch (Exception $e) {
+                    // Let the exception go on its merry way.
+                }
+            }
         }
 
         // If offline grabbing failed, attempt again with online resources
@@ -154,15 +174,13 @@ class Activitypub_explorer
      */
     private function grab_remote_user($url)
     {
+        common_debug("Explorer is grabbing a remote profile for ".$url);
         if (!isset($this->temp_res)) {
             $client    = new HTTPClient();
             $headers   = array();
             $headers[] = 'Accept: application/ld+json; profile="https://www.w3.org/ns/activitystreams"';
             $headers[] = 'User-Agent: GNUSocialBot v0.1 - https://gnu.io/social';
             $response  = $client->get($url, $headers);
-            if (!$response->isOk()) {
-                throw new Exception("Invalid Actor URL.");
-            }
             $res = json_decode($response->getBody(), JSON_UNESCAPED_SLASHES);
         } else {
             $res = $this->temp_res;
@@ -234,6 +252,32 @@ class Activitypub_explorer
         return true;
     }
 
+    /**
+     * Get a ActivityPub Profile from it's uri
+     * Unfortunately GNU Social cache is not truly reliable when handling
+     * potential ActivityPub remote profiles, as so it is important to use
+     * this hacky workaround (at least for now)
+     *
+     * @author Diogo Cordeiro <diogo@fc.up.pt>
+     * @param string $v URL
+     * @return boolean|Activitypub_profile false if fails | Aprofile object if successful
+     */
+    public static function get_aprofile_by_url($v)
+    {
+        $i = Managed_DataObject::getcached("Activitypub_profile", "uri", $v);
+        if (empty($i)) { // false = cache miss
+            $i = new Activitypub_profile;
+            $result = $i->get("uri", $v);
+            if ($result) {
+                // Hit!
+                $i->encache();
+            } else {
+                return false;
+            }
+        }
+        return $i;
+    }
+
     /**
      * Given a valid actor profile url returns its inboxes
      *

utils/postman.php

@@ -168,12 +168,12 @@ class Activitypub_postman
     public function create($notice)
     {
         $data = Activitypub_create::create_to_array(
-                    $notice->getUri(),
+                    $notice->getUrl(),
                     ActivityPubPlugin::actor_uri($this->actor),
-                    Activitypub_notice::notice_to_array($notice)
+                    array_merge(Activitypub_notice::notice_to_array($notice), ['cc' => common_local_url('apActorFollowers', ['id' => $this->actor->getID()]),])
                 );
         if (isset($notice->reply_to)) {
-            $data["object"]["reply_to"] = $notice->getParent()->getUri();
+            $data["object"]["reply_to"] = $notice->getParent()->getUrl();
         }
         $this->client->setBody(json_encode($data));
         foreach ($this->to_inbox() as $inbox) {