Proide application-based handle loads; load Slowvote handles from the application

Summary:
Ref T2715. This is pretty straightforward, I think. Notes:

  - Long term, I want to replace `PhabricatorObjectHandleData` with `PhabricatorObjectQuery` and `PhabricatorHandleQuery`. The former's name is a relic of old Facebook stuff and unusual now that everything else uses normal queries.
  - I simplified the amount of work applications need to do in order to populate handles. The should just need to set names and URIs in most cases.

Test Plan: Used `phid.lookup` and `phid.query` to load slowvote handles. Browsed around to load other handles.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2715

Differential Revision: https://secure.phabricator.com/D6508

src/__phutil_library_map__.php

@@ -1166,6 +1166,7 @@ phutil_register_library_map(array(
     'PhabricatorGlobalLock' => 'infrastructure/util/PhabricatorGlobalLock.php',
     'PhabricatorGlobalUploadTargetView' => 'applications/files/view/PhabricatorGlobalUploadTargetView.php',
     'PhabricatorHandleObjectSelectorDataView' => 'applications/phid/handle/view/PhabricatorHandleObjectSelectorDataView.php',
+    'PhabricatorHandleQuery' => 'applications/phid/query/PhabricatorHandleQuery.php',
     'PhabricatorHash' => 'infrastructure/util/PhabricatorHash.php',
     'PhabricatorHashTestCase' => 'infrastructure/util/__tests__/PhabricatorHashTestCase.php',
     'PhabricatorHeaderView' => 'view/layout/PhabricatorHeaderView.php',
@@ -3144,6 +3145,7 @@ phutil_register_library_map(array(
     'PhabricatorGestureExample' => 'PhabricatorUIExample',
     'PhabricatorGlobalLock' => 'PhutilLock',
     'PhabricatorGlobalUploadTargetView' => 'AphrontView',
+    'PhabricatorHandleQuery' => 'PhabricatorCursorPagedPolicyAwareQuery',
     'PhabricatorHashTestCase' => 'PhabricatorTestCase',
     'PhabricatorHeaderView' => 'AphrontView',
     'PhabricatorHelpController' => 'PhabricatorController',
@@ -3270,6 +3272,7 @@ phutil_register_library_map(array(
     'PhabricatorOAuthServerTestCase' => 'PhabricatorTestCase',
     'PhabricatorOAuthServerTestController' => 'PhabricatorOAuthServerController',
     'PhabricatorOAuthServerTokenController' => 'PhabricatorAuthController',
+    'PhabricatorObjectHandle' => 'PhabricatorPolicyInterface',
     'PhabricatorObjectHandleStatus' => 'PhabricatorObjectHandleConstants',
     'PhabricatorObjectItemListExample' => 'PhabricatorUIExample',
     'PhabricatorObjectItemListView' => 'AphrontTagView',

src/applications/phid/PhabricatorObjectHandle.php

@@ -1,6 +1,7 @@
 <?php
 
-final class PhabricatorObjectHandle {
+final class PhabricatorObjectHandle
+  implements PhabricatorPolicyInterface {
 
   private $uri;
   private $phid;
@@ -38,6 +39,9 @@ final class PhabricatorObjectHandle {
   }
 
   public function getName() {
+    if ($this->name === null) {
+      return pht('Unknown Object (%s)', $this->getTypeName());
+    }
     return $this->name;
   }
 
@@ -99,9 +103,8 @@ final class PhabricatorObjectHandle {
   }
 
   public function getTypeName() {
-    $types = PhabricatorPHIDType::getAllTypes();
+    if ($this->getPHIDType()) {
-    if (isset($types[$this->getType()])) {
+      return $this->getPHIDType()->getTypeName();
-      return $types[$this->getType()]->getTypeName();
     }
 
     static $map = array(
@@ -223,4 +226,27 @@ final class PhabricatorObjectHandle {
     return $name;
   }
 
+  protected function getPHIDType() {
+    $types = PhabricatorPHIDType::getAllTypes();
+    return idx($types, $this->getType());
+  }
+
+
+/* -(  PhabricatorPolicyInterface  )----------------------------------------- */
+
+
+  public function getCapabilities() {
+    return array(
+      PhabricatorPolicyCapability::CAN_VIEW,
+    );
+  }
+
+  public function getPolicy($capability) {
+    return PhabricatorPolicies::POLICY_PUBLIC;
+  }
+
+  public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
+    return false;
+  }
+
 }

src/applications/phid/handle/PhabricatorObjectHandleData.php

@@ -241,9 +241,23 @@ final class PhabricatorObjectHandleData {
   }
 
   public function loadHandles() {
-    $all_objects = $this->loadObjects();
 
-    $types = phid_group_by_type($this->phids);
+    $application_handles = id(new PhabricatorHandleQuery())
+      ->setViewer($this->viewer)
+      ->withPHIDs($this->phids)
+      ->execute();
+
+    // TODO: Move the rest of this into Applications.
+
+    $phid_map = array_fuse($this->phids);
+    foreach ($application_handles as $handle) {
+      if ($handle->isComplete()) {
+        unset($phid_map[$handle->getPHID()]);
+      }
+    }
+
+    $all_objects = $this->loadObjects();
+    $types = phid_group_by_type($phid_map);
 
     $handles = array();
 
@@ -674,26 +688,6 @@ final class PhabricatorObjectHandleData {
           }
           break;
 
-
-        case PhabricatorSlowvotePHIDTypePoll::TYPECONST:
-          foreach ($phids as $phid) {
-            $handle = new PhabricatorObjectHandle();
-            $handle->setPHID($phid);
-            $handle->setType($type);
-            if (empty($objects[$phid])) {
-              $handle->setName('Unknown Slowvote');
-            } else {
-              $poll = $objects[$phid];
-              $handle->setName('V'.$poll->getID());
-              $handle->setFullName(
-                'V'.$poll->getID().': '.$poll->getQuestion());
-              $handle->setURI('/V'.$poll->getID());
-              $handle->setComplete(true);
-            }
-            $handles[$phid] = $handle;
-          }
-          break;
-
         case PhabricatorPHIDConstants::PHID_TYPE_MCRO:
           foreach ($phids as $phid) {
             $handle = new PhabricatorObjectHandle();
@@ -821,6 +815,6 @@ final class PhabricatorObjectHandleData {
       }
     }
 
-    return $handles;
+    return $handles + $application_handles;
   }
 }

src/applications/phid/query/PhabricatorHandleQuery.php

@@ -0,0 +1,66 @@
+<?php
+
+final class PhabricatorHandleQuery
+  extends PhabricatorCursorPagedPolicyAwareQuery {
+
+  private $phids;
+
+  public function withPHIDs(array $phids) {
+    $this->phids = $phids;
+    return $this;
+  }
+
+  public function loadPage() {
+    $types = PhabricatorPHIDType::getAllTypes();
+
+    $phids = $this->phids;
+    if (!$phids) {
+      return array();
+    }
+
+    $objects = id(new PhabricatorObjectQuery())
+      ->withPHIDs($phids)
+      ->setViewer($this->getViewer())
+      ->execute();
+
+    $groups = array();
+    foreach ($phids as $phid) {
+      $type = phid_get_type($phid);
+      $groups[$type][] = $phid;
+    }
+
+    $results = array();
+    foreach ($groups as $type => $phid_group) {
+      $handles = array();
+      foreach ($phid_group as $key => $phid) {
+        if (isset($handles[$phid])) {
+          unset($phid_group[$key]);
+          // The input had a duplicate PHID; just skip it.
+          continue;
+        }
+        $handles[$phid] = id(new PhabricatorObjectHandle())
+          ->setType($type)
+          ->setPHID($phid);
+        if (isset($objects[$phid])) {
+          $handles[$phid]->setComplete(true);
+        }
+      }
+
+      if (isset($types[$type])) {
+        $type_objects = array_select_keys($objects, $phid_group);
+        if ($type_objects) {
+          $have_object_phids = array_keys($type_objects);
+          $types[$type]->loadHandles(
+            $this,
+            array_select_keys($handles, $have_object_phids),
+            $type_objects);
+        }
+      }
+
+      $results += $handles;
+    }
+
+    return $results;
+  }
+
+}

src/applications/phid/type/PhabricatorPHIDType.php

@@ -12,7 +12,39 @@ abstract class PhabricatorPHIDType {
   abstract public function loadObjects(
     PhabricatorObjectQuery $query,
     array $phids);
-  abstract public function loadHandles(array $phids, array $objects);
+
+
+  /**
+   * Populate provided handles with application-specific data, like titles and
+   * URIs.
+   *
+   * NOTE: The `$handles` and `$objects` lists are guaranteed to be nonempty
+   * and have the same keys: subclasses are expected to load information only
+   * for handles with visible objects.
+   *
+   * Because of this guarantee, a safe implementation will typically look like*
+   *
+   *   foreach ($handles as $phid => $handle) {
+   *     $object = $objects[$phid];
+   *
+   *     $handle->setStuff($object->getStuff());
+   *     // ...
+   *   }
+   *
+   * In general, an implementation should call `setName()` and `setURI()` on
+   * each handle at a minimum. See @{class:PhabricatorObjectHandle} for other
+   * handle properties.
+   *
+   * @param PhabricatorHandleQuery          Issuing query object.
+   * @param list<PhabricatorObjectHandle>   Handles to populate with data.
+   * @param list<Object>                    Objects for these PHIDs loaded by
+   *                                        @{method:loadObjects()}.
+   * @return void
+   */
+  abstract public function loadHandles(
+    PhabricatorHandleQuery $query,
+    array $handles,
+    array $objects);
 
   public function canLoadNamedObject($name) {
     return false;

src/applications/slowvote/phid/PhabricatorSlowvotePHIDTypePoll.php

@@ -26,8 +26,18 @@ final class PhabricatorSlowvotePHIDTypePoll extends PhabricatorPHIDType {
       ->execute();
   }
 
-  public function loadHandles(array $phids, array $objects) {
+  public function loadHandles(
-    throw new Exception("TODO");
+    PhabricatorHandleQuery $query,
+    array $handles,
+    array $objects) {
+
+    foreach ($handles as $phid => $handle) {
+      $poll = $objects[$phid];
+
+      $handle->setName('V'.$poll->getID());
+      $handle->setFullName('V'.$poll->getID().': '.$poll->getQuestion());
+      $handle->setURI('/V'.$poll->getID());
+    }
   }
 
   public function canLoadNamedObject($name) {