add param checking and removed default values

Author: TorstenDittmann

docs/storage.md

@@ -110,7 +110,7 @@ GET https://appwrite.io/v1/storage/files/{fileId}/preview
 | borderWidth | integer | Preview image border in pixels. Pass an integer between 0 to 100. Defaults to 0. | 0 |
 | borderColor | string | Preview image border color. Use a valid HEX color, no # is needed for prefix. |  |
 | borderRadius | integer | Preview image border radius in pixels. Pass an integer between 0 to 4000. | 0 |
-| opacity | number | Preview image opacity. Only works with images having an alpha channel (like png). Pass a number between 0 to 1. | 1 |
+| opacity | integer | Preview image opacity. Only works with images having an alpha channel (like png). Pass a number between 0 to 1. | 1 |
 | rotation | integer | Preview image rotation in degrees. Pass an integer between 0 and 360. | 0 |
 | background | string | Preview image background color. Only works with transparent images (png). Use a valid HEX color, no # is needed for prefix. |  |
 | output | string | Output format type (jpeg, jpg, png, gif and webp). |  |

src/Appwrite/Client.php

@@ -35,7 +35,7 @@ class Client
      */
     protected $headers = [
         'content-type' => '',
-        'x-sdk-version' => 'appwrite:php:2.1.1',
+        'x-sdk-version' => 'appwrite:php:2.1.2',
     ];
 
     /**