[5.5] Support custom URLs for AWS storage

src/Illuminate/Filesystem/FilesystemAdapter.php

@@ -350,6 +350,15 @@ public function url($path)
      */
     protected function getAwsUrl($adapter, $path)
     {
+        $config = $this->driver->getConfig();
+
+        // If an explicit base URL has been set on the disk configuration then we will use
+        // it as the base URL instead of the default path. This allows the developer to
+        // have full control over the base path for this filesystem's generated URLs.
+        if (! is_null($url = $config->get('url'))) {
+            return $this->concatPathToUrl($url, $path);
+        }
+
         return $adapter->getClient()->getObjectUrl(
             $adapter->getBucket(), $adapter->getPathPrefix().$path
         );
@@ -381,7 +390,7 @@ protected function getLocalUrl($path)
         // it as the base URL instead of the default path. This allows the developer to
         // have full control over the base path for this filesystem's generated URLs.
         if ($config->has('url')) {
-            return rtrim($config->get('url'), '/').'/'.ltrim($path, '/');
+            return $this->concatPathToUrl($config->get('url'), $path);
         }
 
         $path = '/storage/'.$path;
@@ -460,6 +469,18 @@ public function getRackspaceTemporaryUrl($adapter, $path, $expiration, $options)
         );
     }
 
+    /**
+     * Concatenate a path to a URL.
+     *
+     * @param  string $url
+     * @param  string $path
+     * @return string
+     */
+    protected function concatPathToUrl($url, $path)
+    {
+        return rtrim($url, '/').'/'.ltrim($path, '/');
+    }
+
     /**
      * Get an array of all files in a directory.
      *