Add /F123 shortcut

Summary:
I wanted to point someone on a file uploaded to Phabricator and the normal link is just too long.

I guess that this also improves security. Because pointing someone to the file directly reveals the secret key used in /data/ and it can be served without auth?

We already use `{F123}` so there will be no conflicts in future because we wouldn't want to reuse it for something else.

I promote the link on /file/ - it adds one redirect but I think it's worth it. I also considered making the link from the File ID column but there are already too many links (with some duplicity).

Test Plan:
/file/
/F123 (redirect)
/F9999999999 (404)

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Koolvin

Differential Revision: https://secure.phabricator.com/D2380

src/__phutil_library_map__.php

@@ -630,6 +630,7 @@ phutil_register_library_map(array(
     'PhabricatorFileMacroListController' => 'applications/files/controller/macrolist',
     'PhabricatorFileProxyController' => 'applications/files/controller/proxy',
     'PhabricatorFileProxyImage' => 'applications/files/storage/proxyimage',
+    'PhabricatorFileShortcutController' => 'applications/files/controller/shortcut',
     'PhabricatorFileSideNavView' => 'applications/files/view/sidenav',
     'PhabricatorFileStorageBlob' => 'applications/files/storage/storageblob',
     'PhabricatorFileStorageConfigurationException' => 'applications/files/exception/configuration',
@@ -1556,6 +1557,7 @@ phutil_register_library_map(array(
     'PhabricatorFileMacroListController' => 'PhabricatorFileController',
     'PhabricatorFileProxyController' => 'PhabricatorFileController',
     'PhabricatorFileProxyImage' => 'PhabricatorFileDAO',
+    'PhabricatorFileShortcutController' => 'PhabricatorFileController',
     'PhabricatorFileSideNavView' => 'AphrontView',
     'PhabricatorFileStorageBlob' => 'PhabricatorFileDAO',
     'PhabricatorFileTransformController' => 'PhabricatorFileController',

src/aphront/default/configuration/AphrontDefaultApplicationConfiguration.php

@@ -39,6 +39,7 @@ class AphrontDefaultApplicationConfiguration
         '(?:(?P<subfilter>[^/]+)/)?' =>
           'PhabricatorDirectoryMainController',
       ),
+      '/F(?P<id>\d+)' => 'PhabricatorFileShortcutController',
       '/file/' => array(
         '' => 'PhabricatorFileListController',
         'filter/(?P<filter>\w+)/' => 'PhabricatorFileListController',

src/applications/files/controller/list/PhabricatorFileListController.php

@@ -246,7 +246,8 @@ final class PhabricatorFileListController extends PhabricatorFileController {
         phutil_render_tag(
           'a',
           array(
-            'href' => $file->getBestURI(),
+            // Don't use $file->getBestURI() to improve discoverability of /F.
+            'href' => '/F'.$file->getID(),
           ),
           ($name != '' ? phutil_escape_html($name) : '<em>no name</em>')),
         phutil_escape_html(number_format($file->getByteSize()).' bytes'),

src/applications/files/controller/shortcut/PhabricatorFileShortcutController.php

@@ -0,0 +1,36 @@
+<?php
+
+/*
+ * Copyright 2012 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+final class PhabricatorFileShortcutController
+  extends PhabricatorFileController {
+
+  private $id;
+
+  public function willProcessRequest(array $data) {
+    $this->id = $data['id'];
+  }
+
+  public function processRequest() {
+    $file = id(new PhabricatorFile())->load($this->id);
+    if (!$file) {
+      return new Aphront404Response();
+    }
+    return id(new AphrontRedirectResponse())->setURI($file->getBestURI());
+  }
+
+}

src/applications/files/controller/shortcut/__init__.php

@@ -0,0 +1,17 @@
+<?php
+/**
+ * This file is automatically generated. Lint this module to rebuild it.
+ * @generated
+ */
+
+
+
+phutil_require_module('phabricator', 'aphront/response/404');
+phutil_require_module('phabricator', 'aphront/response/redirect');
+phutil_require_module('phabricator', 'applications/files/controller/base');
+phutil_require_module('phabricator', 'applications/files/storage/file');
+
+phutil_require_module('phutil', 'utils');
+
+
+phutil_require_source('PhabricatorFileShortcutController.php');