feat: Use an extensible document title driver implementation (#3109)

* feat: Use an extensible document title driver implementation
* chore: Add todo to use DI in 2.0

framework/core/src/Extend/Frontend.php

@@ -35,6 +35,7 @@ class Frontend implements ExtenderInterface
     private $removedRoutes = [];
     private $content = [];
     private $preloadArrs = [];
+    private $titleDriver;
 
     /**
      * @param string $frontend: The name of the frontend.
@@ -159,12 +160,23 @@ class Frontend implements ExtenderInterface
         return $this;
     }
 
+    /**
+     * Register a new title driver to change the title of frontend documents.
+     */
+    public function title(string $driverClass): self
+    {
+        $this->titleDriver = $driverClass;
+
+        return $this;
+    }
+
     public function extend(Container $container, Extension $extension = null)
     {
         $this->registerAssets($container, $this->getModuleName($extension));
         $this->registerRoutes($container);
         $this->registerContent($container);
         $this->registerPreloads($container);
+        $this->registerTitleDriver($container);
     }
 
     private function registerAssets(Container $container, string $moduleName): void
@@ -295,4 +307,13 @@ class Frontend implements ExtenderInterface
     {
         return $extension ? $extension->getId() : 'site-custom';
     }
+
+    private function registerTitleDriver(Container $container): void
+    {
+        if ($this->titleDriver) {
+            $container->extend('flarum.frontend.title_driver', function ($driver, Container $container) {
+                return $container->make($this->titleDriver);
+            });
+        }
+    }
 }

framework/core/src/Frontend/Document.php

@@ -9,6 +9,7 @@
 
 namespace Flarum\Frontend;
 
+use Flarum\Frontend\Driver\TitleDriverInterface;
 use Illuminate\Contracts\Support\Renderable;
 use Illuminate\Contracts\View\Factory;
 use Illuminate\Contracts\View\View;
@@ -159,10 +160,6 @@ class Document implements Renderable
      */
     protected $request;
 
-    /**
-     * @param Factory $view
-     * @param array $forumApiDocument
-     */
     public function __construct(Factory $view, array $forumApiDocument, Request $request)
     {
         $this->view = $view;
@@ -202,9 +199,8 @@ class Document implements Renderable
      */
     protected function makeTitle(): string
     {
-        $onHomePage = rtrim($this->request->getUri()->getPath(), '/') === '';
-
-        return ($this->title && ! $onHomePage ? $this->title.' - ' : '').Arr::get($this->forumApiDocument, 'data.attributes.title');
+        // @todo v2.0 inject as dependency instead
+        return resolve(TitleDriverInterface::class)->makeTitle($this, $this->request, $this->forumApiDocument);
     }
 
     /**

framework/core/src/Frontend/Driver/BasicTitleDriver.php

@@ -0,0 +1,24 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Frontend\Driver;
+
+use Flarum\Frontend\Document;
+use Illuminate\Support\Arr;
+use Psr\Http\Message\ServerRequestInterface;
+
+class BasicTitleDriver implements TitleDriverInterface
+{
+    public function makeTitle(Document $document, ServerRequestInterface $request, array $forumApiDocument): string
+    {
+        $onHomePage = rtrim($request->getUri()->getPath(), '/') === '';
+
+        return ($document->title && ! $onHomePage ? $document->title.' - ' : '').Arr::get($forumApiDocument, 'data.attributes.title');
+    }
+}

framework/core/src/Frontend/Driver/TitleDriverInterface.php

@@ -0,0 +1,18 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Frontend\Driver;
+
+use Flarum\Frontend\Document;
+use Psr\Http\Message\ServerRequestInterface;
+
+interface TitleDriverInterface
+{
+    public function makeTitle(Document $document, ServerRequestInterface $request, array $forumApiDocument): string;
+}

framework/core/src/Frontend/FrontendServiceProvider.php

@@ -12,6 +12,8 @@ namespace Flarum\Frontend;
 use Flarum\Foundation\AbstractServiceProvider;
 use Flarum\Foundation\Paths;
 use Flarum\Frontend\Compiler\Source\SourceCollector;
+use Flarum\Frontend\Driver\BasicTitleDriver;
+use Flarum\Frontend\Driver\TitleDriverInterface;
 use Flarum\Http\UrlGenerator;
 use Flarum\Settings\SettingsRepositoryInterface;
 use Illuminate\Contracts\Container\Container;
@@ -107,6 +109,12 @@ class FrontendServiceProvider extends AbstractServiceProvider
             }
         );
 
+        $this->container->singleton(TitleDriverInterface::class, function (Container $container) {
+            return $container->make(BasicTitleDriver::class);
+        });
+
+        $this->container->alias(TitleDriverInterface::class, 'flarum.frontend.title_driver');
+
         $this->container->singleton('flarum.less.config', function (Container $container) {
             return [
                 'config-primary-color'   => [

framework/core/src/helpers.php

@@ -15,9 +15,10 @@ if (! function_exists('resolve')) {
     /**
      * Resolve a service from the container.
      *
-     * @param  string  $name
+     * @template T
+     * @param  class-string<T>|string  $name
      * @param  array  $parameters
-     * @return mixed
+     * @return T|mixed
      */
     function resolve($name, $parameters = [])
     {

framework/core/tests/integration/extenders/FrontendTitleTest.php

@@ -0,0 +1,74 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Tests\integration\extenders;
+
+use Flarum\Extend\Frontend;
+use Flarum\Frontend\Document;
+use Flarum\Frontend\Driver\TitleDriverInterface;
+use Flarum\Testing\integration\RetrievesAuthorizedUsers;
+use Flarum\Testing\integration\TestCase;
+use Psr\Http\Message\ServerRequestInterface;
+
+class FrontendTitleTest extends TestCase
+{
+    use RetrievesAuthorizedUsers;
+
+    protected function setUp(): void
+    {
+        $this->prepareDatabase([
+            'users' => [
+                $this->normalUser(),
+            ],
+            'discussions' => [
+                ['id' => 1, 'title' => 'Test Discussion', 'user_id' => 1, 'first_post_id' => 1]
+            ],
+            'posts' => [
+                ['id' => 1, 'discussion_id' => 1, 'user_id' => 2, 'type' => 'comment', 'content' => '<t><p>can i haz potat?</p></t>'],
+            ],
+        ]);
+
+        $this->setting('forum_title', 'Flarum');
+    }
+
+    /**
+     * @test
+     */
+    public function basic_title_driver_is_used_by_default()
+    {
+        $this->assertTitleEquals('Test Discussion - Flarum');
+    }
+
+    /**
+     * @test
+     */
+    public function custom_title_driver_works_if_set()
+    {
+        $this->extend((new Frontend('forum'))->title(CustomTitleDriver::class));
+
+        $this->assertTitleEquals('CustomTitle');
+    }
+
+    private function assertTitleEquals(string $title): void
+    {
+        $response = $this->send($this->request('GET', '/d/1'));
+
+        preg_match('/\<title\>(?<title>[^<]+)\<\/title\>/m', $response->getBody()->getContents(), $matches);
+
+        $this->assertEquals($title, $matches['title']);
+    }
+}
+
+class CustomTitleDriver implements TitleDriverInterface
+{
+    public function makeTitle(Document $document, ServerRequestInterface $request, array $forumApiDocument): string
+    {
+        return 'CustomTitle';
+    }
+}