Added Hashsids

Added Hashids to create Short URLs based on the current primary key of the urls table. This way is SURE Short URLs wll alway be unique, but the check is made anyway because we allow custom short urls also.

Author: optiroot

app/Services/UrlService.php

@@ -13,6 +13,7 @@
 use App\User;
 use App\Url;
 use Auth;
+use Hashids\Hashids;
 use Illuminate\Support\Str;
 
 
@@ -45,14 +46,36 @@ public function shortenUrl($long_url, $short_url, $privateUrl, $hideUrlStats)
 
         // Iterate until a not-already-created short url is generated
         do {
-            $short_url = Str::random(6);
-            // ! because we need 'false', not 'true'
+            $short_url = $this->generateShortUrl();
         } while ($this->customUrlExisting($short_url));
 
         Url::createShortUrl($long_url, $short_url, $privateUrl, $hideUrlStats);
         return $short_url;
     }
 
+    /**
+     * Generate an unique short URL using hashids. Salt is the APP_KEY, which is always unique
+     *
+     * @return string
+     */
+    public function generateShortUrl()
+    {
+        $hashids = new Hashids(env('APP_KEY'), 4);
+
+        $current = Url::orderBy('id', 'desc')->lockForUpdate()->first();
+
+        // If this is the first Short URL, let's encode a 0
+        if ($current === null) {
+            return $hashids->encode(0);
+        }
+
+        $currentInc = $current->id;
+        $currentInc++;
+
+        return $hashids->encode($currentInc);
+    }
+
+
     /**
      * Check if is possible to use the Custom URL or not
      *

composer.json

@@ -15,6 +15,7 @@
         "fideloper/proxy": "^4.0",
         "geoip2/geoip2": "~2.0",
         "guzzlehttp/guzzle": "^6.3",
+        "hashids/hashids": "^4.0",
         "laravel-frontend-presets/argon": "^1.0",
         "laravel/framework": "5.8.*",
         "laravel/tinker": "^1.0",