[TheFreeNetwork] Do not allow lower priority protocols to handle remote actors already handled by the higher ones

lib/exceptions/alreadyhandledexception.php

@@ -0,0 +1,40 @@
+<?php
+// This file is part of GNU social - https://www.gnu.org/software/social
+//
+// GNU social 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.
+//
+// GNU social 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 GNU social.  If not, see <http://www.gnu.org/licenses/>.
+/**
+ * Class for exception thrown when something was already handled.
+ * Useful to use as a lock when handling a same something in different queues and only one should be attended
+ *
+ * @category  Exception
+ * @author    Diogo Cordeiro <diogo@fc.up.pt>
+ * @copyright 2020 Free Software Foundation, Inc http://www.fsf.org
+ * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
+ */
+
+defined('GNUSOCIAL') || die();
+
+/**
+ * Exception thrown when something was already handled.
+ *
+ * @copyright 2019 Free Software Foundation, Inc http://www.fsf.org
+ * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
+ */
+class AlreadyHandledException extends ServerException
+{
+    public function __construct($msg)
+    {
+        parent::__construct($msg, 202);
+    }
+}

modules/TheFreeNetwork/EVENTS.txt

@@ -1,7 +1,7 @@
 StartTFNLookup: tries to locate a duplicated remote profile by URI; federation plugins must trigger this event before profile insertion
 @param string $uri URI of the remote profile to be inserted
 @param string $class profile class of the federation protocol that triggered the event
-@param int|null &$profile_id profile ID associated with the duplicated remote profile found
+@param int|null &$profile_id profile ID associated with the duplicated remote profile found, throws AlreadyHandledException to warn that the duplicate has priority
 
 EndTFNLookup: deletes a previous duplicated remote profile found; federation plugins must trigget this event after successfully inserting a new profile
 @param string $class profile class of the federation protocol that triggered the event

modules/TheFreeNetwork/README.md

@@ -4,7 +4,7 @@ Making this possible essentially consists in not allowing duplication of remote
 and to ensure that each profile is handled by one and only one federation protocol at a time.
 
 Each newly added federation protocol **must** support all the already supported functionalities by the other federation
-protocols, otherwise this module will be moving between FullFeaturedFederationProtocolProfile and LackyFederationProtocolProfile all the time.
+protocols, otherwise if the LackyFederationProtocolProfile is preferred, the remote actors using it will be limited.
 
 You **must** feed this Module with the list of preferences for each federation protocol, more on that in the following section.
 

modules/TheFreeNetwork/TheFreeNetworkModule.php

@@ -42,6 +42,7 @@ class TheFreeNetworkModule extends Module
     const MODULE_VERSION = '0.1.0alpha0';
 
     public $protocols = null; // protocols TFN should handle
+    public $priority = []; // protocols preferences
 
     private $lrdd = false; // whether LRDD plugin is active or not
 
@@ -56,9 +57,12 @@ class TheFreeNetworkModule extends Module
         // require needed classes
         $plugin_dir = dirname(__DIR__, 2) . DIRECTORY_SEPARATOR . 'plugins';
 
+        $p = 0;
         foreach ($this->protocols as $protocol => $class) {
+            $this->priority[$class] = $p++;
             require_once $plugin_dir . DIRECTORY_SEPARATOR . $protocol . DIRECTORY_SEPARATOR . 'classes' . DIRECTORY_SEPARATOR . $class . '.php';
         }
+        unset($p);
 
         // $lrdd flag
         $this->lrdd = PluginList::isPluginActive("LRDD");
@@ -74,25 +78,31 @@ class TheFreeNetworkModule extends Module
      * @param string $class profile class that triggered this event
      * @param int|null &$profile_id Profile:id associated with the remote entity found
      * @return bool hook flag
+     * @throws AlreadyHandledException Do not allow to create a profile if a preferred protocol already has one
      */
     public function onStartTFNLookup(string $uri, string $class, int &$profile_id = null): bool
     {
-        $profile_id = $this->lookup($uri, $class);
+        [$profile_id, $cls] = $this->lookup($uri, $class);
 
         if (is_null($profile_id)) {
             $perf = common_config('performance', 'high');
 
             if (!$perf && $this->lrdd) {
                 // Force lookup with online resources
-                $profile_id = $this->lookup($uri, $class, true);
+                [$profile_id, $cls] = $this->lookup($uri, $class, true);
             }
         }
 
+        // Lower means higher priority
+        if ($this->priority[$cls] < $this->priority[$class]) {
+            throw new AlreadyHandledException("TheFreeNetworkModule->AlreadyHandled: $cls is preferred over $class");
+        }
+
         return false;
     }
 
     /**
-     * A new remote profile was sucessfully added, delete
+     * A new remote profile was successfully added, delete
      * other remotes associated with the same Profile entity.
      *
      * @param string $class profile class that triggered this event
@@ -146,9 +156,9 @@ class TheFreeNetworkModule extends Module
      * @param string $uri
      * @param string $class
      * @param bool $online
-     * @return int|null Profile:id associated with the remote entity found
+     * @return null|array [Profile:id, class] associated with the remote entity found
      */
-    private function lookup(string $uri, string $class, bool $online = false): ?int
+    private function lookup(string $uri, string $class, bool $online = false): ?array
     {
         if ($online) {
             $this->log(LOG_INFO, 'Searching with online resources for a remote profile with URI: ' . $uri);
@@ -169,7 +179,7 @@ class TheFreeNetworkModule extends Module
                     $profile = $cls::getKV('uri', $alias);
                     if ($profile instanceof $cls) {
                         $this->log(LOG_INFO, 'Found a remote ' . $cls . ' associated with Profile:' . $profile->getID());
-                        return $profile->getID();
+                        return [$profile->getID(), $cls];
                     }
                 }
             }

plugins/ActivityPub/classes/Activitypub_profile.php

@@ -285,8 +285,6 @@ class Activitypub_profile extends Managed_DataObject
         }
 
         $aprofile->created = $aprofile->modified = common_sql_now();
-
-        $aprofile = new Activitypub_profile;
         $aprofile->profile_id = $profile->getID();
         $aprofile->uri = $url;
         $aprofile->nickname = $profile->getNickname();

plugins/ActivityPub/lib/postman.php

@@ -49,7 +49,7 @@ class Activitypub_postman
      * Create a postman to deliver something to someone
      *
      * @param Profile $from sender Profile
-     * @param array $to receiver Profiles
+     * @param array $to receiver AProfiles
      * @throws Exception
      * @author Diogo Cordeiro <diogo@fc.up.pt>
      */

plugins/OStatus/lib/salmonaction.php

@@ -287,7 +287,13 @@ class SalmonAction extends Action
             if (!$this->oprofile instanceof Ostatus_profile) {
                 common_debug("We do not have a local profile to connect to this activity's author. Let's create one.");
                 // ensureActivityObjectProfile throws exception on failure
-                $this->oprofile = Ostatus_profile::ensureActivityObjectProfile($this->activity->actor);
+                try {
+                    $this->oprofile = Ostatus_profile::ensureActivityObjectProfile($this->activity->actor);
+                } catch (AlreadyHandledException $e) {
+                    // Some other federation protocol is handling this profile, let it go.
+                    common_debug('SalmonAction found that this actor already was handled by another federation protocol: ' . $e->getMessage());
+                    return;
+                }
             }
         }