ENH Top page configuration improvements.

_config/config.yml

@@ -24,10 +24,6 @@ SilverStripe\CMS\Controllers\CMSMain:
   extensions:
     - DNADesign\Elemental\Extensions\ElementalCMSMainExtension
 
-SilverStripe\CMS\Model\SiteTree:
-  extensions:
-    topPageSiteTreeExtension: DNADesign\Elemental\TopPage\SiteTreeExtension
-
 SilverStripe\Versioned\VersionedGridFieldItemRequest:
   extensions:
     - 'DNADesign\Elemental\Extensions\GridFieldDetailFormItemRequestExtension'
@@ -39,3 +35,35 @@ Symbiote\GridFieldExtensions\GridFieldAddNewMultiClassHandler:
 SilverStripe\Core\Injector\Injector:
   SilverStripe\CMS\Controllers\CMSSiteTreeFilter_Search:
     class: DNADesign\Elemental\Controllers\ElementSiteTreeFilterSearch
+
+---
+Name: elemental-top-page-default
+---
+
+DNADesign\Elemental\Models\BaseElement:
+  extensions:
+    topPageDataExtension: DNADesign\Elemental\TopPage\DataExtension
+
+DNADesign\Elemental\Models\ElementalArea:
+  extensions:
+    topPageDataExtension: DNADesign\Elemental\TopPage\DataExtension
+
+SilverStripe\CMS\Model\SiteTree:
+  extensions:
+    topPageSiteTreeExtension: DNADesign\Elemental\TopPage\SiteTreeExtension
+
+---
+Name: elemental-top-page-fluent
+After:
+  - elemental-top-page-default
+Only:
+  moduleexists: 'tractorcow/silverstripe-fluent'
+---
+
+DNADesign\Elemental\Models\BaseElement:
+  extensions:
+    topPageDataExtension: DNADesign\Elemental\TopPage\FluentExtension
+
+DNADesign\Elemental\Models\ElementalArea:
+  extensions:
+    topPageDataExtension: DNADesign\Elemental\TopPage\FluentExtension

docs/en/02_advanced_setup.md

@@ -444,21 +444,28 @@ directly on the block as a performance enhancement for this query. A set of exte
 of the box for elements on pages. You can use `$TopPage` in your template to get access to the page, which is more performant
 than using `$Page`.
 
-If your project makes use of the Fluent module, it is recommended to use the following extensions in place of the ones
-above:
+If your project makes use of the Fluent module, this feature will automatically replace `DNADesign\Elemental\TopPage\DataExtension` with `DNADesign\Elemental\TopPage\FluentExtension`.
+
+These variants will also store the locale of the top page on blocks, which simplifies top page lookup in case the locale
+is unknown at the time of page lookup from block context.
+
+The page reference on the blocks can also be useful for maintenance dev tasks, as it's easy to identify which blocks
+belong to which pages in which locale.
+
+In case you need to further customise this setup with your own extension override, one way how to do this is shown below:
 
 ```yml
+---
+Name: my-elemental-config
+After:
+    - elemental-top-page-fluent
+---
+
 DNADesign\Elemental\Models\BaseElement:
   extensions:
-    topPageDataExtension: DNADesign\Elemental\TopPage\FluentExtension
+    topPageDataExtension: App\MyExtension
 
 DNADesign\Elemental\Models\ElementalArea:
   extensions:
-    topPageDataExtension: DNADesign\Elemental\TopPage\FluentExtension
+    topPageDataExtension: App\MyExtension
 ```
-
-These variants will also store the locale of the top page on blocks, which simplifies top page lookup in case the locale
-is unknown at the time of page lookup from block context.
-
-The page reference on the blocks can also be useful for maintenance dev tasks, as it's easy to identify which blocks
-belong to which pages in which locale.

src/Models/BaseElement.php

@@ -6,7 +6,6 @@
 use DNADesign\Elemental\Forms\TextCheckboxGroupField;
 use DNADesign\Elemental\ORM\FieldType\DBObjectType;
 use DNADesign\Elemental\Services\ReorderElements;
-use DNADesign\Elemental\TopPage\DataExtension;
 use Exception;
 use SilverStripe\CMS\Controllers\CMSPageEditController;
 use SilverStripe\CMS\Model\SiteTree;
@@ -91,7 +90,6 @@ class BaseElement extends DataObject implements CMSPreviewable
 
     private static $extensions = [
         Versioned::class,
-        DataExtension::class,
     ];
 
     private static $casting = [

src/Models/ElementalArea.php

@@ -4,7 +4,6 @@
 
 use DNADesign\Elemental\Controllers\ElementController;
 use DNADesign\Elemental\Extensions\ElementalAreasExtension;
-use DNADesign\Elemental\TopPage\DataExtension;
 use SilverStripe\Core\ClassInfo;
 use SilverStripe\Core\Injector\Injector;
 use SilverStripe\Dev\TestOnly;
@@ -37,7 +36,6 @@ class ElementalArea extends DataObject
 
     private static $extensions = [
         Versioned::class,
-        DataExtension::class,
     ];
 
     private static $owns = [