gistfile1.diff

diff --git a/lib/Github/Api/Repository/Assets.php b/lib/Github/Api/Repository/Assets.php
index ad48aaf..cee57d5 100644
--- a/lib/Github/Api/Repository/Assets.php
+++ b/lib/Github/Api/Repository/Assets.php
@@ -74,7 +74,6 @@ class Assets extends AbstractApi
         }
 
         $name = $params['name'];
-        $parameters['body'] = $params['body'];
         $headers['Content-Type'] = $params['content-type'];
 
         // Asset creation requires a separate endpoint, uploads.github.com.
@@ -83,7 +82,15 @@ class Assets extends AbstractApi
         $baseUrl = $this->client->getHttpClient()->client->getBaseUrl();
         $this->client->getHttpClient()->client->setBaseUrl('https://uploads.github.com/');
 
-        $response = $this->post('repos/'.rawurlencode($username).'/'.rawurlencode($repository).'/releases/'.rawurlencode($id).'/assets?name='. $name, $parameters, $headers);
+        $apiPath = sprintf(
+            'repos/%s/%s/releaeses/%s/assets?name=%s',
+            rawurlencode($username),
+            rawurlencode($repository),
+            rawurlencode($id),
+            $name
+        );
+
+        $response = $this->post($apiPath, array('body' => $params['body']), $headers);
 
         // Reset the base url.
         $this->client->getHttpClient()->client->setBaseUrl($baseUrl);
diff --git a/lib/Github/HttpClient/HttpClient.php b/lib/Github/HttpClient/HttpClient.php
index 88c2b25..1ab0631 100644
--- a/lib/Github/HttpClient/HttpClient.php
+++ b/lib/Github/HttpClient/HttpClient.php
@@ -173,9 +173,14 @@ class HttpClient implements HttpClientInterface
     protected function createRequest($httpMethod, $path, array $parameters = array(), array $headers = array())
     {
         if ('GET' !== $httpMethod) {
-            $requestBody = count($parameters) === 0
-                ? null : json_encode($parameters, empty($parameters) ? JSON_FORCE_OBJECT : 0)
-            ;
+            if (1 === count($parameters) && isset($parameters['body'])) {
+                $requestBody = $parameters['body'];
+            } else {
+                $requestBody = count($parameters) === 0
+                    ? null : json_encode($parameters, empty($parameters) ? JSON_FORCE_OBJECT : 0)
+                ;
+            }
+
             $options = array();
         } else {
             $requestBody = null;