Add Inertia SSR directives

composer.json

@@ -30,9 +30,10 @@
         "laravel/framework": "^6.0|^7.0|^8.74"
     },
     "require-dev": {
-        "roave/security-advisories": "dev-master",
+        "mockery/mockery": "^1.3.3",
         "orchestra/testbench": "^4.0|^5.0|^6.4",
-        "phpunit/phpunit": "^8.0|^9.5.8"
+        "phpunit/phpunit": "^8.0|^9.5.8",
+        "roave/security-advisories": "dev-master"
     },
     "extra": {
         "laravel": {

config/inertia.php

@@ -2,6 +2,28 @@
 
 return [
 
+    /*
+    |--------------------------------------------------------------------------
+    | Server Side Rendering
+    |--------------------------------------------------------------------------
+    |
+    | These options configures if and how Inertia uses Server Side Rendering
+    | to pre-render the initial visits made to your application's pages.
+    |
+    | Do note that enabling these options will NOT automatically make SSR work,
+    | as a separate rendering service needs to be available. To learn more,
+    | please visit https://inertiajs.com/server-side-rendering
+    |
+    */
+
+    'ssr' => [
+
+        'enabled' => false,
+
+        'url' => 'http://127.0.0.1:8080/render',
+
+    ],
+
     /*
     |--------------------------------------------------------------------------
     | Testing

src/Directive.php

@@ -0,0 +1,52 @@
+<?php
+
+namespace Inertia;
+
+class Directive
+{
+    /**
+     * Compiles the "@inertia" directive.
+     *
+     * @param  string  $expression
+     * @return string
+     */
+    public static function compile($expression = ''): string
+    {
+        $id = trim(trim($expression), "\'\"") ?: 'app';
+
+        $template = '<?php
+            if (!isset($__inertiaSsr)) {
+                $__inertiaSsr = app(\Inertia\Ssr\Gateway::class)->dispatch($page);
+            }
+
+            if ($__inertiaSsr instanceof \Inertia\Ssr\Response) {
+                echo $__inertiaSsr->body;
+            } else {
+                ?><div id="'.$id.'" data-page="{{ json_encode($page) }}"></div><?php
+            }
+        ?>';
+
+        return implode(' ', array_map('trim', explode("\n", $template)));
+    }
+
+    /**
+     * Compiles the "@inertiaHead" directive.
+     *
+     * @param  string  $expression
+     * @return string
+     */
+    public static function compileHead($expression = ''): string
+    {
+        $template = '<?php
+            if (!isset($__inertiaSsr)) {
+                $__inertiaSsr = app(\Inertia\Ssr\Gateway::class)->dispatch($page);
+            }
+
+            if ($__inertiaSsr instanceof \Inertia\Ssr\Response) {
+                echo $__inertiaSsr->head;
+            }
+        ?>';
+
+        return implode(' ', array_map('trim', explode("\n", $template)));
+    }
+}

src/ServiceProvider.php

@@ -9,6 +9,8 @@
 use Illuminate\Support\ServiceProvider as BaseServiceProvider;
 use Illuminate\Testing\TestResponse;
 use Illuminate\View\FileViewFinder;
+use Inertia\Ssr\Gateway;
+use Inertia\Ssr\HttpGateway;
 use Inertia\Testing\TestResponseMacros;
 use LogicException;
 use ReflectionException;
@@ -18,6 +20,7 @@ class ServiceProvider extends BaseServiceProvider
     public function register(): void
     {
         $this->app->singleton(ResponseFactory::class);
+        $this->app->bind(Gateway::class, HttpGateway::class);
 
         $this->mergeConfigFrom(
             __DIR__.'/../config/inertia.php',
@@ -39,19 +42,18 @@ public function register(): void
 
     public function boot(): void
     {
-        $this->registerBladeDirective();
+        $this->registerBladeDirectives();
         $this->registerConsoleCommands();
 
         $this->publishes([
             __DIR__.'/../config/inertia.php' => config_path('inertia.php'),
         ]);
     }
 
-    protected function registerBladeDirective(): void
+    protected function registerBladeDirectives(): void
     {
-        Blade::directive('inertia', function () {
-            return '<div id="app" data-page="{{ json_encode($page) }}"></div>';
-        });
+        Blade::directive('inertia', [Directive::class, 'compile']);
+        Blade::directive('inertiaHead', [Directive::class, 'compileHead']);
     }
 
     protected function registerConsoleCommands(): void

src/Ssr/Gateway.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace Inertia\Ssr;
+
+interface Gateway
+{
+    /**
+     * Dispatch the Inertia page to the Server Side Rendering engine.
+     *
+     * @param  array  $page
+     * @return Response|null
+     */
+    public function dispatch(array $page): ?Response;
+}

src/Ssr/HttpGateway.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace Inertia\Ssr;
+
+use Exception;
+use Illuminate\Support\Facades\Config;
+use Illuminate\Support\Facades\Http;
+
+class HttpGateway implements Gateway
+{
+    /**
+     * Dispatch the Inertia page to the Server Side Rendering engine.
+     *
+     * @param  array  $page
+     * @return Response|null
+     */
+    public function dispatch(array $page): ?Response
+    {
+        if (! Config::get('inertia.ssr.enabled', false)) {
+            return null;
+        }
+
+        $url = Config::get('inertia.ssr.url', 'http://127.0.0.1:8080/render');
+
+        try {
+            $response = Http::post($url, $page)->throw()->json();
+        } catch (Exception $e) {
+            return null;
+        }
+
+        return new Response(
+            implode("\n", $response['head']),
+            $response['body']
+        );
+    }
+}

src/Ssr/Response.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Inertia\Ssr;
+
+class Response
+{
+    /**
+     * @var string
+     */
+    public $head;
+
+    /**
+     * @var string
+     */
+    public $body;
+
+    /**
+     * Prepare the Inertia Server Side Rendering (SSR) response.
+     *
+     * @param  string  $head
+     * @param  string  $body
+     */
+    public function __construct(string $head, string $body)
+    {
+        $this->head = $head;
+        $this->body = $body;
+    }
+}

tests/ControllerTest.php

@@ -20,8 +20,7 @@ public function test_controller_returns_an_inertia_response(): void
 
         $response = $this->get('/');
 
-        $page = $response->viewData('page');
-        $this->assertEquals($page, [
+        $this->assertEquals($response->viewData('page'), [
             'component' => 'User/Edit',
             'props' => [
                 'user' => ['name' => 'Jonathan'],

tests/DirectiveTest.php

@@ -0,0 +1,145 @@
+<?php
+
+namespace Inertia\Tests;
+
+use Illuminate\Filesystem\Filesystem;
+use Illuminate\Support\Facades\Config;
+use Illuminate\View\Compilers\BladeCompiler;
+use Illuminate\View\Engines\PhpEngine;
+use Illuminate\View\Factory;
+use Illuminate\View\View;
+use Inertia\Directive;
+use Inertia\Ssr\Gateway;
+use Inertia\Tests\Stubs\FakeGateway;
+use Mockery as m;
+
+class DirectiveTest extends TestCase
+{
+    /**
+     * @var Filesystem|m\MockInterface
+     */
+    private $filesystem;
+
+    /**
+     * @var BladeCompiler
+     */
+    protected $compiler;
+
+    /**
+     * Example Page Objects.
+     */
+    protected const EXAMPLE_PAGE_OBJECT = ['component' => 'Foo/Bar', 'props' => ['foo' => 'bar'], 'url' => '/test', 'version' => ''];
+
+    public function setUp(): void
+    {
+        parent::setUp();
+
+        $this->app->bind(Gateway::class, FakeGateway::class);
+        $this->filesystem = m::mock(Filesystem::class);
+
+        $this->compiler = new BladeCompiler($this->filesystem, __DIR__.'/cache/views');
+        $this->compiler->directive('inertia', [Directive::class, 'compile']);
+        $this->compiler->directive('inertiaHead', [Directive::class, 'compileHead']);
+    }
+
+    protected function tearDown(): void
+    {
+        m::close();
+        parent::tearDown();
+    }
+
+    protected function renderView($contents, $data = [])
+    {
+        // First, we'll create a temporary file, and use compileString to 'emulate' compilation of our view.
+        // This skips caching, and a bunch of other logic that's not relevant for what we need here.
+        $path = tempnam(sys_get_temp_dir(), 'inertia_tests_render_');
+        file_put_contents($path, $this->compiler->compileString($contents));
+
+        // Next, we'll 'render' out compiled view.
+        $view = new View(
+            m::mock(Factory::class),
+            new PhpEngine(new Filesystem()),
+            'fake-view',
+            $path,
+            $data
+        );
+
+        // Then, we'll just hack and slash our way to success..
+        $view->getFactory()->allows('incrementRender')->once();
+        $view->getFactory()->allows('callComposer')->once();
+        $view->getFactory()->allows('getShared')->once()->andReturn([]);
+        $view->getFactory()->allows('decrementRender')->once();
+        $view->getFactory()->allows('flushStateIfDoneRendering')->once();
+        $view->getFactory()->allows('flushState');
+
+        try {
+            $output = $view->render();
+            @unlink($path);
+        } catch (\Throwable $e) {
+            @unlink($path);
+            throw $e;
+        }
+
+        return $output;
+    }
+
+    public function test_inertia_directive_renders_the_root_element(): void
+    {
+        $html = '<div id="app" data-page="{&quot;component&quot;:&quot;Foo\/Bar&quot;,&quot;props&quot;:{&quot;foo&quot;:&quot;bar&quot;},&quot;url&quot;:&quot;\/test&quot;,&quot;version&quot;:&quot;&quot;}"></div>';
+
+        $this->assertSame($html, $this->renderView('@inertia', ['page' => self::EXAMPLE_PAGE_OBJECT]));
+        $this->assertSame($html, $this->renderView('@inertia()', ['page' => self::EXAMPLE_PAGE_OBJECT]));
+        $this->assertSame($html, $this->renderView('@inertia("")', ['page' => self::EXAMPLE_PAGE_OBJECT]));
+        $this->assertSame($html, $this->renderView("@inertia('')", ['page' => self::EXAMPLE_PAGE_OBJECT]));
+    }
+
+    public function test_inertia_directive_renders_server_side_rendered_content_when_enabled(): void
+    {
+        Config::set(['inertia.ssr.enabled' => true]);
+
+        $this->assertSame(
+            '<p>This is some example SSR content</p>',
+            $this->renderView('@inertia', ['page' => self::EXAMPLE_PAGE_OBJECT])
+        );
+    }
+
+    public function test_inertia_directive_can_use_a_different_root_element_id(): void
+    {
+        $html = '<div id="foo" data-page="{&quot;component&quot;:&quot;Foo\/Bar&quot;,&quot;props&quot;:{&quot;foo&quot;:&quot;bar&quot;},&quot;url&quot;:&quot;\/test&quot;,&quot;version&quot;:&quot;&quot;}"></div>';
+
+        $this->assertSame($html, $this->renderView('@inertia(foo)', ['page' => self::EXAMPLE_PAGE_OBJECT]));
+        $this->assertSame($html, $this->renderView("@inertia('foo')", ['page' => self::EXAMPLE_PAGE_OBJECT]));
+        $this->assertSame($html, $this->renderView('@inertia("foo")', ['page' => self::EXAMPLE_PAGE_OBJECT]));
+    }
+
+    public function test_inertia_head_directive_renders_nothing(): void
+    {
+        $this->assertEmpty($this->renderView('@inertiaHead', ['page' => self::EXAMPLE_PAGE_OBJECT]));
+    }
+
+    public function test_inertia_head_directive_renders_server_side_rendered_head_elements_when_enabled(): void
+    {
+        Config::set(['inertia.ssr.enabled' => true]);
+
+        $this->assertSame(
+            "<meta charset=\"UTF-8\" />\n<title inertia>Example SSR Title</title>\n",
+            $this->renderView('@inertiaHead', ['page' => self::EXAMPLE_PAGE_OBJECT])
+        );
+    }
+
+    public function test_the_server_side_rendering_request_is_dispatched_only_once_per_request(): void
+    {
+        Config::set(['inertia.ssr.enabled' => true]);
+        $this->app->instance(Gateway::class, $gateway = new FakeGateway());
+
+        $view = "<!DOCTYPE html>\n<html>\n<head>\n@inertiaHead\n</head>\n<body>\n@inertia\n</body>\n</html>";
+        $expected = "<!DOCTYPE html>\n<html>\n<head>\n<meta charset=\"UTF-8\" />\n<title inertia>Example SSR Title</title>\n</head>\n<body>\n<p>This is some example SSR content</p></body>\n</html>";
+
+        $this->assertSame(
+            $expected,
+            $this->renderView($view, ['page' => self::EXAMPLE_PAGE_OBJECT])
+        );
+
+        $this->assertSame(1, $gateway->times);
+    }
+}

tests/ResponseTest.php

@@ -44,7 +44,7 @@ public function test_server_response(): void
         $this->assertSame('Jonathan', $page['props']['user']['name']);
         $this->assertSame('/user/123', $page['url']);
         $this->assertSame('123', $page['version']);
-        $this->assertSame('<div id="app" data-page="{&quot;component&quot;:&quot;User\/Edit&quot;,&quot;props&quot;:{&quot;user&quot;:{&quot;name&quot;:&quot;Jonathan&quot;}},&quot;url&quot;:&quot;\/user\/123&quot;,&quot;version&quot;:&quot;123&quot;}"></div>'."\n", $view->render());
+        $this->assertSame('<div id="app" data-page="{&quot;component&quot;:&quot;User\/Edit&quot;,&quot;props&quot;:{&quot;user&quot;:{&quot;name&quot;:&quot;Jonathan&quot;}},&quot;url&quot;:&quot;\/user\/123&quot;,&quot;version&quot;:&quot;123&quot;}"></div>', $view->render());
     }
 
     public function test_xhr_response(): void

tests/ServiceProviderTest.php

@@ -11,10 +11,7 @@ class ServiceProviderTest extends TestCase
 {
     public function test_blade_directive_is_registered(): void
     {
-        $directives = Blade::getCustomDirectives();
-
-        $this->assertArrayHasKey('inertia', $directives);
-        $this->assertEquals('<div id="app" data-page="{{ json_encode($page) }}"></div>', $directives['inertia']());
+        $this->assertArrayHasKey('inertia', Blade::getCustomDirectives());
     }
 
     public function test_request_macro_is_registered(): void