Add "--background" and "--count" flags to "bin/webhook call"

Summary:
See PHI1794, which reports an issue where a large number of queued webhook calls led to connection exhaustion. To make this easier to reproduce and test, add "--count" and "--background" flags to "bin/webhook call".

This primarily supports "bin/webook call ... --background --count 10000" to quickly fill the queue with a bunch of calls.

Test Plan: Ran `bin/webhook call` in foreground and background modes, with and without counts. Saw appropriate console and queue behavior.

Differential Revision: https://secure.phabricator.com/D21368

src/applications/herald/management/HeraldWebhookCallManagementWorkflow.php

@@ -28,6 +28,17 @@ final class HeraldWebhookCallManagementWorkflow
             'name' => 'secure',
             'help' => pht('Set the "secure" flag on the request.'),
           ),
+          array(
+            'name' => 'count',
+            'param' => 'N',
+            'help' => pht('Make a total of __N__ copies of the call.'),
+          ),
+          array(
+            'name' => 'background',
+            'help' => pht(
+              'Instead of making calls in the foreground, add the tasks '.
+              'to the daemon queue.'),
+          ),
         ));
   }
 
@@ -41,6 +52,17 @@ final class HeraldWebhookCallManagementWorkflow
           'Specify a webhook to call with "--id".'));
     }
 
+    $count = $args->getArg('count');
+    if ($count === null) {
+      $count = 1;
+    }
+
+    if ($count <= 0) {
+      throw new PhutilArgumentUsageException(
+        pht(
+          'Specified "--count" must be larger than 0.'));
+    }
+
     $hook = id(new HeraldWebhookQuery())
       ->setViewer($viewer)
       ->withIDs(array($id))
@@ -69,6 +91,8 @@ final class HeraldWebhookCallManagementWorkflow
       $object = head($objects);
     }
 
+    $is_background = $args->getArg('background');
+
     $xaction_query =
       PhabricatorApplicationTransactionQuery::newQueryForObject($object);
 
@@ -80,6 +104,22 @@ final class HeraldWebhookCallManagementWorkflow
 
     $application_phid = id(new PhabricatorHeraldApplication())->getPHID();
 
+    if ($is_background) {
+      echo tsprintf(
+        "%s\n",
+        pht(
+          'Queueing webhook calls...'));
+      $progress_bar = id(new PhutilConsoleProgressBar())
+        ->setTotal($count);
+    } else {
+      echo tsprintf(
+        "%s\n",
+        pht(
+          'Calling webhook...'));
+      PhabricatorWorker::setRunAllTasksInProcess(true);
+    }
+
+    for ($ii = 0; $ii < $count; $ii++) {
       $request = HeraldWebhookRequest::initializeNewWebhookRequest($hook)
         ->setObjectPHID($object->getPHID())
         ->setIsTestAction(true)
@@ -89,9 +129,11 @@ final class HeraldWebhookCallManagementWorkflow
         ->setTransactionPHIDs(mpull($xactions, 'getPHID'))
         ->save();
 
-    PhabricatorWorker::setRunAllTasksInProcess(true);
       $request->queueCall();
 
+      if ($is_background) {
+        $progress_bar->update(1);
+      } else {
         $request->reload();
 
         echo tsprintf(
@@ -99,6 +141,12 @@ final class HeraldWebhookCallManagementWorkflow
           pht(
             'Success, got HTTP %s from webhook.',
             $request->getErrorCode()));
+      }
+    }
+
+    if ($is_background) {
+      $progress_bar->done();
+    }
 
     return 0;
   }