Make "public" pastes meaningfully visible to logged-out users

Summary:
  - Introduce `shouldAllowPublic()`, indicating that logged-out users are OK in a controller if the install is configured to permit public policies.
  - Make Paste views and lists allow public users.
  - Make UI do sensible things with respect to disabling links, etc.
  - Improve behavior of "you need to login" with respect to policy exceptions and Ajax requests.

Test Plan: Looked at "public" paste, saw all unavailable UI disabled, clicked it, got appropraite prompts.

Reviewers: vrana, btrahan

Reviewed By: vrana

CC: aran

Maniphest Tasks: T603

Differential Revision: https://secure.phabricator.com/D3502

src/aphront/AphrontController.php

@@ -50,7 +50,6 @@ abstract class AphrontController {
     return $controller->processRequest();
   }
 
-
   final public function setCurrentApplication(
     PhabricatorApplication $current_application) {
 

src/aphront/configuration/AphrontDefaultApplicationConfiguration.php

@@ -336,6 +336,18 @@ class AphrontDefaultApplicationConfiguration
     }
 
     if ($ex instanceof PhabricatorPolicyException) {
+
+      if (!$user->isLoggedIn()) {
+        // If the user isn't logged in, just give them a login form. This is
+        // probably a generally more useful response than a policy dialog that
+        // they have to click through to get a login form.
+        //
+        // Possibly we should add a header here like "you need to login to see
+        // the thing you are trying to look at".
+        $login_controller = new PhabricatorLoginController($request);
+        return $login_controller->processRequest();
+      }
+
       $content =
         '<div class="aphront-policy-exception">'.
           phutil_escape_html($ex->getMessage()).

src/applications/auth/controller/PhabricatorLoginController.php

@@ -25,12 +25,33 @@ final class PhabricatorLoginController
 
   public function processRequest() {
     $request = $this->getRequest();
+    $user = $request->getUser();
 
-    if ($request->getUser()->getPHID()) {
+    if ($user->isLoggedIn()) {
       // Kick the user out if they're already logged in.
       return id(new AphrontRedirectResponse())->setURI('/');
     }
 
+    if ($request->isAjax()) {
+
+      // We end up here if the user clicks a workflow link that they need to
+      // login to use. We give them a dialog saying "You need to login..".
+
+      if ($request->isDialogFormPost()) {
+        return id(new AphrontRedirectResponse())->setURI(
+          $request->getRequestURI());
+      }
+
+      $dialog = new AphrontDialogView();
+      $dialog->setUser($user);
+      $dialog->setTitle('Login Required');
+      $dialog->appendChild('<p>You must login to continue.</p>');
+      $dialog->addSubmitButton('Login');
+      $dialog->addCancelButton('/', 'Cancel');
+
+      return id(new AphrontDialogResponse())->setDialog($dialog);
+    }
+
     if ($request->isConduit()) {
 
       // A common source of errors in Conduit client configuration is getting

src/applications/base/controller/PhabricatorController.php

@@ -21,6 +21,14 @@ abstract class PhabricatorController extends AphrontController {
   private $handles;
 
   public function shouldRequireLogin() {
+
+    // If this install is configured to allow public resources and the
+    // controller works in public mode, allow the request through.
+    $is_public_allowed = PhabricatorEnv::getEnvConfig('policy.allow-public');
+    if ($is_public_allowed && $this->shouldAllowPublic()) {
+      return false;
+    }
+
     return true;
   }
 
@@ -32,6 +40,10 @@ abstract class PhabricatorController extends AphrontController {
     return true;
   }
 
+  public function shouldAllowPublic() {
+    return false;
+  }
+
   public function shouldRequireEmailVerification() {
     $need_verify = PhabricatorUserEmail::isEmailVerificationRequired();
     $need_login = $this->shouldRequireLogin();

src/applications/paste/controller/PhabricatorPasteController.php

@@ -19,6 +19,8 @@
 abstract class PhabricatorPasteController extends PhabricatorController {
 
   public function buildSideNavView(PhabricatorPaste $paste = null) {
+    $user = $this->getRequest()->getUser();
+
     $nav = new AphrontSideNavFilterView();
     $nav->setBaseURI(new PhutilURI($this->getApplicationURI('filter/')));
 
@@ -28,11 +30,18 @@ abstract class PhabricatorPasteController extends PhabricatorController {
     }
 
     $nav->addLabel('Create');
-    $nav->addFilter('edit', 'New Paste', $this->getApplicationURI());
+    $nav->addFilter(
+      'edit',
+      'New Paste',
+      $this->getApplicationURI(),
+      $relative = false,
+      $class = ($user->isLoggedIn() ? null : 'disabled'));
 
     $nav->addSpacer();
     $nav->addLabel('Pastes');
+    if ($user->isLoggedIn()) {
       $nav->addFilter('my', 'My Pastes');
+    }
     $nav->addFilter('all', 'All Pastes');
 
     return $nav;

src/applications/paste/controller/PhabricatorPasteListController.php

@@ -18,6 +18,10 @@
 
 final class PhabricatorPasteListController extends PhabricatorPasteController {
 
+  public function shouldRequireLogin() {
+    return false;
+  }
+
   private $filter;
 
   public function willProcessRequest(array $data) {

src/applications/paste/controller/PhabricatorPasteViewController.php

@@ -18,6 +18,10 @@
 
 final class PhabricatorPasteViewController extends PhabricatorPasteController {
 
+  public function shouldAllowPublic() {
+    return true;
+  }
+
   private $id;
   private $handles;
 
@@ -98,6 +102,8 @@ final class PhabricatorPasteViewController extends PhabricatorPasteController {
       $paste,
       PhabricatorPolicyCapability::CAN_EDIT);
 
+    $can_fork = $user->isLoggedIn();
+
     return id(new PhabricatorActionListView())
       ->setUser($user)
       ->setObject($paste)
@@ -105,6 +111,8 @@ final class PhabricatorPasteViewController extends PhabricatorPasteController {
         id(new PhabricatorActionView())
           ->setName(pht('Fork This Paste'))
           ->setIcon('fork')
+          ->setDisabled(!$can_fork)
+          ->setWorkflow(!$can_fork)
           ->setHref($this->getApplicationURI('?parent='.$paste->getID())))
       ->addAction(
         id(new PhabricatorActionView())