(dev/core#4433) WordPress::url() - By default, choose frontend or backend based on route

CRM/Core/Menu.php

@@ -280,6 +280,33 @@ public static function build(&$menu) {
     self::buildAdminLinks($menu);
   }
 
+  /**
+   * Determine whether a route should canonically use a frontend or backend UI.
+   *
+   * @param string $path
+   *   Ex: 'civicrm/contribute/transact'
+   * @return bool
+   *   TRUE if the route is marked with 'is_public=1'.
+   */
+  public static function isPublicRoute(string $path): bool {
+    // A page-view may include hundreds of links - so don't hit DB for every link. Use cache.
+    // In default+demo builds, the list of public routes is much smaller than the list of
+    // private routes (roughly 1:10; ~50 entries vs ~450 entries). Cache the smaller list.
+    $cache = Civi::cache('long');
+    $index = $cache->get('PublicRouteIndex');
+    if ($index === NULL) {
+      $routes = CRM_Core_DAO::executeQuery('SELECT id, path FROM civicrm_menu WHERE is_public = 1')
+        ->fetchMap('id', 'path');
+      if (empty($routes)) {
+        Civi::log()->warning('isPublicRoute() should not be called before the menu has been built.');
+        return FALSE;
+      }
+      $index = array_fill_keys(array_values($routes), TRUE);
+      $cache->set('PublicRouteIndex', $index);
+    }
+    return isset($index[$path]);
+  }
+
   /**
    * This function recomputes menu from xml and populates civicrm_menu.
    *
@@ -291,6 +318,7 @@ public static function store($truncate = TRUE) {
       $query = 'TRUNCATE civicrm_menu';
       CRM_Core_DAO::executeQuery($query);
     }
+    Civi::cache('long')->delete('PublicRouteIndex');
     $menuArray = self::items($truncate);
 
     self::build($menuArray);

CRM/Core/xml/Menu/Misc.xml

@@ -129,6 +129,7 @@
     <path>civicrm/asset/builder</path>
     <page_callback>\Civi\Core\AssetBuilder::pageRun</page_callback>
     <access_arguments>*always allow*</access_arguments>
+    <is_public>1</is_public>
   </item>
   <item>
      <path>civicrm/contribute/ajax/tableview</path>

CRM/Utils/System/Base.php

@@ -111,6 +111,10 @@ public function postURL($action) {
   /**
    * Generate the url string to a CiviCRM path.
    *
+   * Note: The options `$frontend` and `$forceBackend` are opposites. If you use exactly one (and not
+   * the other), then the URL will follow your request. If you leave the default values, or if you
+   * give incompatible values, then we will use the route's preferred default (from `civicrm_menu.is_public`).
+   *
    * @param string $path
    *   The path being linked to, such as "civicrm/add".
    * @param string $query

CRM/Utils/System/WordPress.php

@@ -313,6 +313,17 @@ public function url(
       $this->loadBootStrap();
     }
 
+    // If caller didn't express a clear preference for frontend xor backend, then use default.
+    // Aside: I definitely find it confusing that this decision is spread across two variables.
+    if ($frontend === $forceBackend) {
+      if (CRM_Core_Menu::isPublicRoute($path)) {
+        $frontend = TRUE;
+      }
+      else {
+        $forceBackend = TRUE;
+      }
+    }
+
     // When on the front-end.
     if ($config->userFrameworkFrontend) {
 

tests/phpunit/CRM/Core/MenuTest.php

@@ -135,4 +135,9 @@ public function testGetArrayForPathArgs($inputString, $expectedArray) {
     $this->assertEquals($expectedArray, $actual);
   }
 
+  public function testIsPublicRoute(): void {
+    $this->assertEquals(FALSE, \CRM_Core_Menu::isPublicRoute('civicrm/contribute'));
+    $this->assertEquals(TRUE, \CRM_Core_Menu::isPublicRoute('civicrm/contribute/transact'));
+  }
+
 }