Support basic export of user accounts

Summary:
Depends on D18934. Ref T13046. Add support for the new export flow to a second application.

My goal here is mostly just to make sure that this is general enough to work in more than one place, and exporting user accounts seems plausible as a useful feature, although we do see occasional requests for this feature exactly (like <https://discourse.phabricator-community.org/t/users-export-to-csv/968>).

The exported data may not truly be useful for much (no disabled/admin/verified/MFA flags, no external account data, no email addresses for policy reasons) but we can expand it as use cases arise.

Test Plan: Exported user accounts in several formats.

Reviewers: amckinley

Reviewed By: amckinley

Maniphest Tasks: T13046

Differential Revision: https://secure.phabricator.com/D18935

src/applications/base/PhabricatorApplication.php

@@ -623,7 +623,7 @@ abstract class PhabricatorApplication
   }
 
   protected function getQueryRoutePattern($base = null) {
-    return $base.'(?:query/(?P<queryKey>[^/]+)/(?:(?P<queryAction>[^/]+)/))?';
+    return $base.'(?:query/(?P<queryKey>[^/]+)/(?:(?P<queryAction>[^/]+)/)?)?';
   }
 
   protected function getProfileMenuRouting($controller) {

src/applications/people/application/PhabricatorPeopleApplication.php

@@ -41,7 +41,7 @@ final class PhabricatorPeopleApplication extends PhabricatorApplication {
   public function getRoutes() {
     return array(
       '/people/' => array(
-        '(query/(?P<key>[^/]+)/)?' => 'PhabricatorPeopleListController',
+        $this->getQueryRoutePattern() => 'PhabricatorPeopleListController',
         'logs/(?:query/(?P<queryKey>[^/]+)/)?'
           => 'PhabricatorPeopleLogsController',
         'invite/' => array(

src/applications/people/controller/PhabricatorPeopleListController.php

@@ -16,7 +16,7 @@ final class PhabricatorPeopleListController
       PeopleBrowseUserDirectoryCapability::CAPABILITY);
 
     $controller = id(new PhabricatorApplicationSearchController())
-      ->setQueryKey($request->getURIData('key'))
+      ->setQueryKey($request->getURIData('queryKey'))
       ->setSearchEngine(new PhabricatorPeopleSearchEngine())
       ->setNavigation($this->buildSideNavView());
 

src/applications/people/query/PhabricatorPeopleSearchEngine.php

@@ -320,4 +320,41 @@ final class PhabricatorPeopleSearchEngine
     return $result;
   }
 
+  protected function newExportFields() {
+    return array(
+      id(new PhabricatorIDExportField())
+        ->setKey('id')
+        ->setLabel(pht('ID')),
+      id(new PhabricatorPHIDExportField())
+        ->setKey('phid')
+        ->setLabel(pht('PHID')),
+      id(new PhabricatorStringExportField())
+        ->setKey('username')
+        ->setLabel(pht('Username')),
+      id(new PhabricatorStringExportField())
+        ->setKey('realName')
+        ->setLabel(pht('Real Name')),
+      id(new PhabricatorEpochExportField())
+        ->setKey('created')
+        ->setLabel(pht('Date Created')),
+    );
+  }
+
+  public function newExport(array $users) {
+    $viewer = $this->requireViewer();
+
+    $export = array();
+    foreach ($users as $user) {
+      $export[] = array(
+        'id' => $user->getID(),
+        'phid' => $user->getPHID(),
+        'username' => $user->getUsername(),
+        'realName' => $user->getRealName(),
+        'created' => $user->getDateCreated(),
+      );
+    }
+
+    return $export;
+  }
+
 }

src/applications/search/controller/PhabricatorApplicationSearchController.php

@@ -396,10 +396,13 @@ final class PhabricatorApplicationSearchController
         ->setViewer($viewer)
         ->withQueryKeys(array($query_key))
         ->executeOne();
+    } else {
+      $saved_query = null;
+    }
+
     if (!$saved_query) {
       return new Aphront404Response();
     }
-    }
 
     $cancel_uri = $engine->getQueryResultsPageURI($query_key);