Add GetTransactionDetailsRequest method. (#30)

src/GetTransactionDetailsRequest.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace CommerceGuys\AuthNet;
+
+use GuzzleHttp\Client;
+use CommerceGuys\AuthNet\Request\RequestInterface;
+
+/**
+ * Retrieve detailed information about a specific transaction.
+ *
+ * @link http://developer.authorize.net/api/reference/index.html#transaction-reporting-get-transaction-details
+ */
+class GetTransactionDetailsRequest extends BaseApiRequest
+{
+    protected $transId;
+
+    public function __construct(
+        Configuration $configuration,
+        Client $client,
+        $transId
+    ) {
+        parent::__construct($configuration, $client);
+        $this->transId = $transId;
+    }
+
+    protected function attachData(RequestInterface $request)
+    {
+        $request->addData('transId', $this->transId);
+    }
+}