Implement PhabricatorDestructibleInterface for event triggers

Summary: Ref T6881. When stuff with triggers is destroyed, it should destroy the triggers.

Test Plan: Will test in Instances.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T6881

Differential Revision: https://secure.phabricator.com/D11435

src/__phutil_library_map__.php

@@ -5884,7 +5884,10 @@ phutil_register_library_map(array(
     'PhabricatorWorkerTaskData' => 'PhabricatorWorkerDAO',
     'PhabricatorWorkerTaskDetailController' => 'PhabricatorDaemonController',
     'PhabricatorWorkerTestCase' => 'PhabricatorTestCase',
-    'PhabricatorWorkerTrigger' => 'PhabricatorWorkerDAO',
+    'PhabricatorWorkerTrigger' => array(
+      'PhabricatorWorkerDAO',
+      'PhabricatorDestructibleInterface',
+    ),
     'PhabricatorWorkerTriggerEvent' => 'PhabricatorWorkerDAO',
     'PhabricatorWorkerTriggerPHIDType' => 'PhabricatorPHIDType',
     'PhabricatorWorkerTriggerQuery' => 'PhabricatorOffsetPagedQuery',

src/infrastructure/daemon/workers/storage/PhabricatorWorkerTrigger.php

@@ -1,7 +1,9 @@
 <?php
 
 final class PhabricatorWorkerTrigger
-  extends PhabricatorWorkerDAO {
+  extends PhabricatorWorkerDAO
+  implements
+    PhabricatorDestructibleInterface {
 
   protected $triggerVersion;
   protected $clockClass;
@@ -127,4 +129,22 @@ final class PhabricatorWorkerTrigger
     return $this;
   }
 
+
+/* -(  PhabricatorDestructibleInterface  )----------------------------------- */
+
+
+  public function destroyObjectPermanently(
+    PhabricatorDestructionEngine $engine) {
+
+    $this->openTransaction();
+      queryfx(
+        $this->establishConnection('w'),
+        'DELETE FROM %T WHERE triggerID = %d',
+        id(new PhabricatorWorkerTriggerEvent())->getTableName(),
+        $this->getID());
+
+      $this->delete();
+    $this->saveTransaction();
+  }
+
 }