MINOR: implementing featured blog posts as a widget

_config/config.yml

@@ -4,3 +4,12 @@ Name: blogconfig
 SilverStripe\Security\Member:
   extensions:
     - SilverStripe\Blog\Model\BlogMemberExtension
+
+---
+Name: featuredpostswidget
+Only:
+  moduleexists: widgets
+---
+SilverStripe\Blog\Model\BlogPost:
+  extensions:
+    - SilverStripe\Blog\Model\BlogPostFeaturedExtension

src/Model/BlogPostFeaturedExtension.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace SilverStripe\Blog\Model;
+
+use SilverStripe\ORM\DataExtension;
+use SilverStripe\Forms\FieldList;
+use SilverStripe\Forms\CheckboxField;
+
+/**
+ * Adds a checkbox field for featured blog posts widget.
+ */
+class BlogPostFeaturedExtension extends DataExtension
+{
+    /**
+     * @var array
+     */
+    private static $db = [
+        'FeaturedInWidget' => 'Boolean',
+    ];
+
+    /**
+     * {@inheritdoc}
+     */
+    public function updateCMSFields(FieldList $fields)
+    {
+        // Add the checkbox in.
+        $fields->addFieldToTab(
+            'Root.PostOptions',
+            new CheckboxField("FeaturedInWidget", _t(__CLASS__ . '.FEATURED', 'Include Post in Feature Widget'))
+        );
+
+        return $fields;
+    }
+}

src/Widgets/BlogFeaturedPostsWidget.php

@@ -0,0 +1,93 @@
+<?php
+
+namespace SilverStripe\Blog\Widgets;
+
+use SilverStripe\Blog\Model\Blog;
+use SilverStripe\Control\Director;
+use SilverStripe\Forms\DropdownField;
+use SilverStripe\Forms\FieldList;
+use SilverStripe\Forms\NumericField;
+use SilverStripe\ORM\DataList;
+use SilverStripe\Widgets\Model\Widget;
+
+if (!class_exists(Widget::class)) {
+    return;
+}
+
+/**
+ * @method Blog Blog()
+ *
+ * @property int $NumberOfPosts
+ */
+class BlogFeaturedPostsWidget extends Widget
+{
+    /**
+     * @var string
+     */
+    private static $title = 'Featured Posts';
+
+    /**
+     * @var string
+     */
+    private static $cmsTitle = 'Featured Posts';
+
+    /**
+     * @var string
+     */
+    private static $description = 'Displays a list of featured blog posts.';
+
+    /**
+     * @var array
+     */
+    private static $db = [
+        'NumberOfPosts' => 'Int',
+    ];
+
+    /**
+     * @var array
+     */
+    private static $has_one = [
+        'Blog' => Blog::class,
+    ];
+
+    /**
+     * @var string
+     */
+    private static $table_name = 'BlogFeaturedPostsWidget';
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getCMSFields()
+    {
+        $this->beforeUpdateCMSFields(function ($fields) {
+            /**
+             * @var FieldList $fields
+             */
+            $fields->merge([
+                DropdownField::create('BlogID', _t(__CLASS__ . '.Blog', 'Blog'), Blog::get()->map()),
+                NumericField::create('NumberOfPosts', _t(__CLASS__ . '.NumberOfPosts', 'Number of Posts'))
+            ]);
+        });
+
+        return parent::getCMSFields();
+    }
+
+    /**
+     * @return array|DataList
+     */
+    public function getPosts()
+    {
+        $blog = $this->Blog();
+
+        if ($blog) {
+            return $blog->getBlogPosts()
+                ->filter('ID:not', Director::get_current_page()->ID)
+                ->filter('FeaturedInWidget', true)
+                ->sort('RAND()')
+                ->limit($this->NumberOfPosts);
+        }
+
+        return [];
+    }
+}

src/Widgets/BlogFeaturedPostsWidgetController.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace SilverStripe\Blog\Widgets;
+
+use SilverStripe\Widgets\Model\WidgetController;
+
+if (!class_exists(WidgetController::class)) {
+    return;
+}
+
+class BlogFeaturedPostsWidgetController extends WidgetController
+{
+
+}

templates/SilverStripe/Blog/Widgets/BlogFeaturedPostsWidget.ss

@@ -0,0 +1,12 @@
+<% if $Posts %>
+	<ul>
+		<% loop $Posts %>
+			<li>
+				<a href="$Link" title="$Title">
+					<span class="arrow">&rarr;</span>
+					<span class="text">$Title</span>
+				</a>
+			</li>
+		<% end_loop %>
+	</ul>
+<% end_if %>