Frontend refactor (#1471)

Refactor Frontend + Asset code

- Use Laravel's Filesystem component for asset IO, meaning theoretically
  assets should be storable on S3 etc.

- More reliable checking for asset recompilation when debug mode is on,
  so you don't have to constantly delete the compiled assets to force
  a recompile. Should also fix issues with locale JS files being
  recompiled with the same name and cached.

- Remove JavaScript minification, because it will be done by Webpack
  (exception is for the TextFormatter JS).

- Add support for JS sourcemaps.

- Separate frontend view and assets completely. This is an important
  distinction because frontend assets are compiled independent of a
  request, whereas putting together a view depends on a request.

- Bind frontend view/asset factory instances to the container (in
  service providers) rather than subclassing. Asset and content
  populators can be added to these factories – these are simply objects
  that populate the asset compilers or the view with information.

- Add RouteHandlerFactory functions that make it easy to hook up a
  frontend controller with a frontend instance ± some content.

- Remove the need for "nojs"

- Fix cache:clear command

- Recompile assets when settings/enabled extensions change

src/Frontend/Content/ContentInterface.php

@@ -0,0 +1,24 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Frontend\Content;
+
+use Flarum\Frontend\HtmlDocument;
+use Psr\Http\Message\ServerRequestInterface as Request;
+
+interface ContentInterface
+{
+    /**
+     * @param HtmlDocument $document
+     * @param Request $request
+     */
+    public function populate(HtmlDocument $document, Request $request);
+}

src/Frontend/Content/CorePayload.php

@@ -0,0 +1,99 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Frontend\Content;
+
+use Flarum\Api\Client;
+use Flarum\Api\Controller\ShowUserController;
+use Flarum\Frontend\HtmlDocument;
+use Flarum\Locale\LocaleManager;
+use Flarum\User\User;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface as Request;
+
+class CorePayload implements ContentInterface
+{
+    /**
+     * @var LocaleManager
+     */
+    private $locales;
+
+    /**
+     * @var Client
+     */
+    private $api;
+
+    /**
+     * @param LocaleManager $locales
+     * @param Client $api
+     */
+    public function __construct(LocaleManager $locales, Client $api)
+    {
+        $this->locales = $locales;
+        $this->api = $api;
+    }
+
+    public function populate(HtmlDocument $document, Request $request)
+    {
+        $document->payload = array_merge(
+            $document->payload,
+            $this->buildPayload($document, $request)
+        );
+    }
+
+    private function buildPayload(HtmlDocument $document, Request $request)
+    {
+        $data = $this->getDataFromApiDocument($document->getForumApiDocument());
+
+        $actor = $request->getAttribute('actor');
+
+        if ($actor->exists) {
+            $user = $this->getUserApiDocument($actor);
+            $data = array_merge($data, $this->getDataFromApiDocument($user));
+        }
+
+        return [
+            'resources' => $data,
+            'session' => [
+                'userId' => $actor->id,
+                'csrfToken' => $request->getAttribute('session')->token()
+            ],
+            'locales' => $this->locales->getLocales(),
+            'locale' => $request->getAttribute('locale')
+        ];
+    }
+
+    private function getDataFromApiDocument(array $apiDocument): array
+    {
+        $data[] = $apiDocument['data'];
+
+        if (isset($apiDocument['included'])) {
+            $data = array_merge($data, $apiDocument['included']);
+        }
+
+        return $data;
+    }
+
+    private function getUserApiDocument(User $user): array
+    {
+        // TODO: to avoid an extra query, something like
+        // $controller = new ShowUserController(new PreloadedUserRepository($user));
+
+        return $this->getResponseBody(
+            $this->api->send(ShowUserController::class, $user, ['id' => $user->id])
+        );
+    }
+
+    private function getResponseBody(ResponseInterface $response)
+    {
+        return json_decode($response->getBody(), true);
+    }
+}

src/Frontend/Content/Layout.php

@@ -0,0 +1,36 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Frontend\Content;
+
+use Flarum\Frontend\HtmlDocument;
+use Psr\Http\Message\ServerRequestInterface as Request;
+
+class Layout implements ContentInterface
+{
+    /**
+     * @var string
+     */
+    protected $layoutView;
+
+    /**
+     * @param string $layoutView
+     */
+    public function __construct(string $layoutView)
+    {
+        $this->layoutView = $layoutView;
+    }
+
+    public function populate(HtmlDocument $document, Request $request)
+    {
+        $document->layoutView = $this->layoutView;
+    }
+}

src/Frontend/Content/Meta.php

@@ -0,0 +1,50 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Frontend\Content;
+
+use Flarum\Frontend\HtmlDocument;
+use Psr\Http\Message\ServerRequestInterface as Request;
+
+class Meta implements ContentInterface
+{
+    public function populate(HtmlDocument $document, Request $request)
+    {
+        $document->meta = array_merge($document->meta, $this->buildMeta($document));
+        $document->head = array_merge($document->head, $this->buildHead($document));
+    }
+
+    private function buildMeta(HtmlDocument $document)
+    {
+        $forumApiDocument = $document->getForumApiDocument();
+
+        $meta = [
+            'viewport' => 'width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1',
+            'description' => array_get($forumApiDocument, 'data.attributes.forumDescription'),
+            'theme-color' => array_get($forumApiDocument, 'data.attributes.themePrimaryColor')
+        ];
+
+        return $meta;
+    }
+
+    private function buildHead(HtmlDocument $document)
+    {
+        $head = [
+            'font' => '<link rel="stylesheet" href="//fonts.googleapis.com/css?family=Open+Sans:400italic,700italic,400,700,600">'
+        ];
+
+        if ($faviconUrl = array_get($document->getForumApiDocument(), 'data.attributes.faviconUrl')) {
+            $head['favicon'] = '<link rel="shortcut icon" href="'.e($faviconUrl).'">';
+        }
+
+        return $head;
+    }
+}