Modernize user and repository "delete" workflows and improve documentation

Summary:
Fixes T8830. Fixes T13364.

  - The inability to destroy objects from the web UI is intentional. Make this clear in the messaging, which is somewhat out of date and partly reflects an earlier era when things could be destroyed.
  - `bin/remove destroy` can't rewind time. Document expectations around the "put the cat back in the bag" use case.

Test Plan: Read documentation, clicked through both workflows.

Maniphest Tasks: T13364, T8830

Differential Revision: https://secure.phabricator.com/D20694

resources/celerity/map.php

@@ -9,7 +9,7 @@ return array(
   'names' => array(
     'conpherence.pkg.css' => '3c8a0668',
     'conpherence.pkg.js' => '020aebcf',
-    'core.pkg.css' => 'af983028',
+    'core.pkg.css' => '5a4a5010',
     'core.pkg.js' => '73a06a9f',
     'differential.pkg.css' => '8d8360fb',
     'differential.pkg.js' => '0b037a4f',
@@ -24,7 +24,7 @@ return array(
     'rsrc/audio/basic/ting.mp3' => 'a6b6540e',
     'rsrc/css/aphront/aphront-bars.css' => '4a327b4a',
     'rsrc/css/aphront/dark-console.css' => '7f06cda2',
-    'rsrc/css/aphront/dialog-view.css' => 'b70c70df',
+    'rsrc/css/aphront/dialog-view.css' => '874f5c06',
     'rsrc/css/aphront/list-filter-view.css' => 'feb64255',
     'rsrc/css/aphront/multi-column.css' => 'fbc00ba3',
     'rsrc/css/aphront/notification.css' => '30240bd2',
@@ -530,7 +530,7 @@ return array(
     'almanac-css' => '2e050f4f',
     'aphront-bars' => '4a327b4a',
     'aphront-dark-console-css' => '7f06cda2',
-    'aphront-dialog-view-css' => 'b70c70df',
+    'aphront-dialog-view-css' => '874f5c06',
     'aphront-list-filter-view-css' => 'feb64255',
     'aphront-multi-column-view-css' => 'fbc00ba3',
     'aphront-panel-view-css' => '46923d46',

src/applications/diffusion/controller/DiffusionRepositoryEditDeleteController.php

@@ -17,32 +17,31 @@ final class DiffusionRepositoryEditDeleteController
       ->setRepository($repository)
       ->getPanelURI();
 
-    $dialog = new AphrontDialogView();
-    $text_1 = pht(
-      'If you really want to delete the repository, run this command from '.
-      'the command line:');
-    $command = csprintf(
-      'phabricator/ $ ./bin/remove destroy %R',
-      $repository->getMonogram());
-    $text_2 = pht(
-      'Repositories touch many objects and as such deletes are '.
-      'prohibitively expensive to run from the web UI.');
-    $body = phutil_tag(
-      'div',
-      array(
-        'class' => 'phabricator-remarkup',
-      ),
-      array(
-        phutil_tag('p', array(), $text_1),
-        phutil_tag('p', array(),
-          phutil_tag('tt', array(), $command)),
-        phutil_tag('p', array(), $text_2),
-      ));
+    $doc_uri = PhabricatorEnv::getDoclink(
+      'Permanently Destroying Data');
 
     return $this->newDialog()
-      ->setTitle(pht('Really want to delete the repository?'))
-      ->appendChild($body)
-      ->addCancelButton($panel_uri, pht('Okay'));
+      ->setTitle(pht('Delete Repository'))
+      ->appendParagraph(
+        pht(
+          'To permanently destroy this repository, run this command from '.
+          'the command line:'))
+      ->appendCommand(
+        csprintf(
+          'phabricator/ $ ./bin/remove destroy %R',
+          $repository->getMonogram()))
+      ->appendParagraph(
+        pht(
+          'Repositories can not be permanently destroyed from the web '.
+          'interface. See %s in the documentation for more information.',
+          phutil_tag(
+            'a',
+            array(
+              'href' => $doc_uri,
+              'target' => '_blank',
+            ),
+            pht('Permanently Destroying Data'))))
+      ->addCancelButton($panel_uri, pht('Close'));
   }
 
 }

src/applications/diffusion/management/DiffusionRepositoryBasicsManagementPanel.php

@@ -155,8 +155,6 @@ final class DiffusionRepositoryBasicsManagementPanel
         ->setName(pht('Delete Repository'))
         ->setHref($delete_uri)
         ->setIcon('fa-times')
-        ->setColor(PhabricatorActionView::RED)
-        ->setDisabled(true)
         ->setWorkflow(true));
 
     return $this->newCurtainView()

src/applications/people/controller/PhabricatorPeopleDeleteController.php

@@ -17,58 +17,35 @@ final class PhabricatorPeopleDeleteController
 
     $manage_uri = $this->getApplicationURI("manage/{$id}/");
 
-    if ($user->getPHID() == $viewer->getPHID()) {
-      return $this->buildDeleteSelfResponse($manage_uri);
-    }
-
-    $str1 = pht(
-      'Be careful when deleting users! This will permanently and '.
-      'irreversibly destroy this user account.');
-
-    $str2 = pht(
-      'If this user interacted with anything, it is generally better to '.
-      'disable them, not delete them. If you delete them, it will no longer '.
-      'be possible to (for example) search for objects they created, and you '.
-      'will lose other information about their history. Disabling them '.
-      'instead will prevent them from logging in, but will not destroy any of '.
-      'their data.');
-
-    $str3 = pht(
-      'It is generally safe to delete newly created users (and test users and '.
-      'so on), but less safe to delete established users. If possible, '.
-      'disable them instead.');
-
-    $str4 = pht('To permanently destroy this user, run this command:');
-
-    $form = id(new AphrontFormView())
-      ->setUser($viewer)
-      ->appendRemarkupInstructions(
-        csprintf(
-          "  phabricator/ $ ./bin/remove destroy %R\n",
-          '@'.$user->getUsername()));
+    $doc_uri = PhabricatorEnv::getDoclink(
+      'Permanently Destroying Data');
 
     return $this->newDialog()
-      ->setWidth(AphrontDialogView::WIDTH_FORM)
-      ->setTitle(pht('Permanently Delete User'))
-      ->setShortTitle(pht('Delete User'))
-      ->appendParagraph($str1)
-      ->appendParagraph($str2)
-      ->appendParagraph($str3)
-      ->appendParagraph($str4)
-      ->appendChild($form->buildLayoutView())
+      ->setTitle(pht('Delete User'))
+      ->appendParagraph(
+        pht(
+          'To permanently destroy this user, run this command from the '.
+          'command line:'))
+      ->appendCommand(
+        csprintf(
+          'phabricator/ $ ./bin/remove destroy %R',
+          $user->getMonogram()))
+      ->appendParagraph(
+        pht(
+          'Unless you have a very good reason to delete this user, consider '.
+          'disabling them instead.'))
+      ->appendParagraph(
+        pht(
+          'Users can not be permanently destroyed from the web interface. '.
+          'See %s in the documentation for more information.',
+          phutil_tag(
+            'a',
+            array(
+              'href' => $doc_uri,
+              'target' => '_blank',
+            ),
+            pht('Permanently Destroying Data'))))
       ->addCancelButton($manage_uri, pht('Close'));
   }
 
-  private function buildDeleteSelfResponse($cancel_uri) {
-    return $this->newDialog()
-      ->setTitle(pht('You Shall Journey No Farther'))
-      ->appendParagraph(
-        pht(
-          'As you stare into the gaping maw of the abyss, something '.
-          'holds you back.'))
-      ->appendParagraph(pht('You can not delete your own account.'))
-      ->addCancelButton($cancel_uri, pht('Turn Back'));
-  }
-
-
 }

src/docs/user/field/permanently_destroying_data.diviner

@@ -0,0 +1,92 @@
+@title Permanently Destroying Data
+@group fieldmanual
+
+How to permanently destroy data and manage leaked secrets.
+
+Overview
+========
+
+Phabricator intentionally makes it difficult to permanently destroy data, but
+provides a command-line tool for destroying objects if you're certain that
+you want to destroy something.
+
+**Disable vs Destroy**: Most kinds of objects can be disabled, deactivated,
+closed, or archived. These operations place them in inactive states and
+preserve their transaction history.
+
+(NOTE) Disabling (rather than destroying) objects is strongly recommended
+unless you have a very good reason to want to permanently destroy an object.
+
+
+Destroying Data
+===============
+
+To permanently destroy an object, run this command from the command line:
+
+```
+phabricator/ $ ./bin/remove destroy <object>
+```
+
+The `<object>` may be an object monogram or PHID. For instance, you can use
+`@alice` to destroy a particular user, or `T123` to destroy a particular task.
+
+(IMPORTANT) This operation is permanent and can not be undone.
+
+
+CLI Access Required
+===================
+
+In almost all cases, Phabricator requires operational access from the CLI to
+permanently destroy data. One major reason for this requirement is that it
+limits the reach of an attacker who compromises a privileged account.
+
+The web UI is generally append-only and actions generally leave an audit
+trail, usually in the transaction log. Thus, an attacker who compromises an
+account but only gains access to the web UI usually can not do much permanent
+damage and usually can not hide their actions or cover their tracks.
+
+Another reason that destroying data is hard is simply that it's permanent and
+can not be undone, so there's no way to recover from mistakes.
+
+
+Leaked Secrets
+==============
+
+Sometimes you may want to destroy an object because it has leaked a secret,
+like an API key or another credential. For example, an engineer might
+accidentally send a change for review which includes a sensitive private key.
+
+No Phabricator command can rewind time, and once data is written to Phabricator
+the cat is often out of the bag: it has often been transmitted to external
+systems which Phabricator can not interact with via email, webhooks, API calls,
+repository mirroring, CDN caching, and so on. You can try to clean up the mess,
+but you're generally already too late.
+
+The `bin/remove destroy` command will make a reasonable attempt to completely
+destroy objects, but this is just an attempt. It can not unsend email or uncall
+the API, and no command can rewind time and undo a leak.
+
+**Revoking Credentials**: If Phabricator credentials were accidentally
+disclosed, you can revoke them so they no longer function. See
+@{article:Revoking Credentials} for more information.
+
+
+Preventing Leaks
+================
+
+Because time can not be rewound, it is best to prevent sensitive data from
+leaking in the first place. Phabricator supports some technical measures that
+can make it more difficult to accidentally disclose secrets:
+
+**Differential Diff Herald Rules**: You can write "Differential Diff" rules
+in Herald that reject diffs before they are written to disk by using the
+"Block diff with message" action.
+
+These rules can reject diffs based on affected file names or file content.
+This is a coarse tool, but rejecting diffs which contain strings like
+`BEGIN RSA PRIVATE KEY` may make it more difficult to accidentally disclose
+certain secrets.
+
+**Commit Content Herald Rules**: For hosted repositories, you can write
+"Commit Hook: Commit Content" rules in Herald which reject pushes that contain
+commit which match certain rules (like file name or file content rules).

src/docs/user/userguide/diffusion_managing.diviner

@@ -169,8 +169,8 @@ start working normally.
 Basics: Delete Repository
 =========================
 
-Repositories can not be deleted from the web UI, so this option is always
-disabled. Clicking it gives you information about how to delete a repository.
+Repositories can not be deleted from the web UI, so this option only gives you
+information about how to delete a repository.
 
 Repositories can only be deleted from the command line, with `bin/remove`:
 
@@ -178,9 +178,8 @@ Repositories can only be deleted from the command line, with `bin/remove`:
 $ ./bin/remove destroy <repository>
 ```
 
-WARNING: This command will issue you a dire warning about the severity of the
-action you are taking. Heed this warning. You are **strongly discouraged** from
-destroying repositories. Instead, deactivate them.
+This command will permanently destroy the repository. For more information
+about destroying things, see @{article:Permanently Destroying Data}.
 
 
 Policies

src/view/AphrontDialogView.php

@@ -161,15 +161,36 @@ final class AphrontDialogView
   }
 
   public function appendParagraph($paragraph) {
-    return $this->appendChild(
-      phutil_tag(
-        'p',
-        array(
-          'class' => 'aphront-dialog-view-paragraph',
-        ),
-        $paragraph));
+    return $this->appendParagraphTag($paragraph);
   }
 
+  public function appendCommand($command) {
+    $command_tag = phutil_tag('tt', array(), $command);
+    return $this->appendParagraphTag(
+      $command_tag,
+      'aphront-dialog-view-command');
+  }
+
+  private function appendParagraphTag($content, $classes = null) {
+    if ($classes) {
+      $classes = (array)$classes;
+    } else {
+      $classes = array();
+    }
+
+    array_unshift($classes, 'aphront-dialog-view-paragraph');
+
+    $paragraph_tag = phutil_tag(
+      'p',
+      array(
+        'class' => implode(' ', $classes),
+      ),
+      $content);
+
+    return $this->appendChild($paragraph_tag);
+  }
+
+
   public function appendList(array $items) {
     $listitems = array();
     foreach ($items as $item) {

webroot/rsrc/css/aphront/dialog-view.css

@@ -158,6 +158,11 @@
   margin-top: 16px;
 }
 
+.aphront-dialog-view-command {
+  padding: 8px 16px;
+  background: {$greybackground};
+}
+
 .device-desktop .aphront-dialog-flush .phui-oi-list-view {
   margin: 0;
   padding: 0;