+ try {
+ $this->oprofile = Ostatus_profile::getActorProfile($this->activity);
+ if (!$this->oprofile instanceof Ostatus_profile) {
+ throw new UnknownUriException($this->activity->actor->id);
+ }
+ } catch (UnknownUriException $e) {
+ // Apparently we didn't find the Profile object based on our URI,
+ // so OStatus doesn't have it with this URI in ostatus_profile.
+ // Try to look it up again, remote side may have changed from http to https
+ // or maybe publish an acct: URI now instead of an http: URL.
+ //
+ // Steps:
+ // 1. Check the newly received URI. Who does it say it is?
+ // 2. Compare these alleged identities to our local database.
+ // 3. If we found any locally stored identities, ask it about its aliases.
+ // 4. Do any of the aliases from our known identity match the recently introduced one?
+ //
+ // Example: We have stored http://example.com/user/1 but this URI says https://example.com/user/1
+ common_debug('No local Profile object found for a magicsigned activity author URI: '.$e->object_uri);
+ $disco = new Discovery();
+ $xrd = $disco->lookup($e->object_uri);
+ // Step 1: We got a bunch of discovery data for https://example.com/user/1 which includes
+ // aliases https://example.com/user and hopefully our original http://example.com/user/1 too
+ $all_ids = array_merge(array($xrd->subject), $xrd->aliases);
+
+ if (!in_array($e->object_uri, $all_ids)) {
+ common_debug('The activity author URI we got was not listed itself when doing discovery on it.');
+ throw $e;
+ }
+
+ // Go through each reported alias from lookup to see if we know this already
+ foreach ($all_ids as $aliased_uri) {
+ $oprofile = Ostatus_profile::getKV('uri', $aliased_uri);
+ if (!$oprofile instanceof Ostatus_profile) {
+ continue; // unknown locally, check the next alias
+ }
+ // Step 2: We found the alleged http://example.com/user/1 URI in our local database,
+ // but this can't be trusted yet because anyone can publish any alias.
+ common_debug('Found a local Ostatus_profile for "'.$e->object_uri.'" with this URI: '.$aliased_uri);
+
+ // We found an existing OStatus profile, but is it really the same? Do a callback to the URI's origin
+ // Step 3: lookup our previously known http://example.com/user/1 webfinger etc.
+ $xrd = $disco->lookup($oprofile->getUri()); // getUri returns ->uri, which we filtered on earlier
+ $doublecheck_aliases = array_merge(array($xrd->subject), $xrd->aliases);
+ common_debug('Trying to match known "'.$aliased_uri.'" against its returned aliases: '.implode(' ', $doublecheck_aliases));
+ // if we find our original URI here, it is a legitimate alias
+ // Step 4: Is the newly introduced https://example.com/user/1 URI in the list of aliases
+ // presented by http://example.com/user/1 (i.e. do they both say they are the same identity?)
+ if (in_array($e->object_uri, $doublecheck_aliases)) {
+ $oprofile->updateUriKeys($e->object_uri, DiscoveryHints::fromXRD($xrd));
+ $this->oprofile = $oprofile;
+ break; // don't iterate through aliases anymore
+ }
+ }
+
+ // We might end up here after $all_ids is iterated through without a $this->oprofile value,
+ if (!$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);
+ }