オカズリンクのデータを保存するようにした (#4)

app/Listeners/LinkCollector.php

@@ -0,0 +1,54 @@
+<?php
+
+namespace App\Listeners;
+
+use App\Events\LinkDiscovered;
+use App\Metadata;
+use App\MetadataResolver\MetadataResolver;
+use App\Utilities\Formatter;
+use Illuminate\Queue\InteractsWithQueue;
+use Illuminate\Contracts\Queue\ShouldQueue;
+
+class LinkCollector
+{
+    /** @var Formatter */
+    private $formatter;
+    /** @var MetadataResolver */
+    private $metadataResolver;
+
+    /**
+     * Create the event listener.
+     *
+     * @return void
+     */
+    public function __construct(Formatter $formatter, MetadataResolver $metadataResolver)
+    {
+        $this->formatter = $formatter;
+        $this->metadataResolver = $metadataResolver;
+    }
+
+    /**
+     * Handle the event.
+     *
+     * @param  LinkDiscovered  $event
+     * @return void
+     */
+    public function handle(LinkDiscovered $event)
+    {
+        // URLの正規化
+        $url = $this->formatter->normalizeUrl($event->url);
+
+        // 無かったら取得
+        // TODO: ある程度古かったら再取得とかありだと思う
+        $metadata = Metadata::find($url);
+        if ($metadata == null) {
+            $resolved = $this->metadataResolver->resolve($url);
+            Metadata::create([
+                'url' => $url,
+                'title' => $resolved->title,
+                'description' => $resolved->description,
+                'image' => $resolved->image
+            ]);
+        }
+    }
+}