diff --git a/backend/composer.json b/backend/composer.json
index 1fe0274..e3820f0 100644
--- a/backend/composer.json
+++ b/backend/composer.json
@@ -67,7 +67,8 @@
     "3rdparty/woocommerce-product-bundles": "*"
   },
   "require-dev": {
-    "vlucas/phpdotenv": "2.5.0"
+    "vlucas/phpdotenv": "2.5.0",
+    "guzzlehttp/guzzle": "6.3.3"
   },
   "extra": {
     "installer-paths": {
diff --git a/backend/composer.lock b/backend/composer.lock
index b59d0b9..f58dd1a 100644
--- a/backend/composer.lock
+++ b/backend/composer.lock
@@ -1,7 +1,7 @@
 {
     "_readme": [
         "This file locks the dependencies of your project to a known state",
-        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
     ],
     "content-hash": "302f569929ecdaf4d349b0bf764de74c",
@@ -630,6 +630,237 @@
         }
     ],
     "packages-dev": [
+        {
+            "name": "guzzlehttp/guzzle",
+            "version": "6.3.3",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/guzzle/guzzle.git",
+                "reference": "407b0cb880ace85c9b63c5f9551db498cb2d50ba"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/guzzle/guzzle/zipball/407b0cb880ace85c9b63c5f9551db498cb2d50ba",
+                "reference": "407b0cb880ace85c9b63c5f9551db498cb2d50ba",
+                "shasum": ""
+            },
+            "require": {
+                "guzzlehttp/promises": "^1.0",
+                "guzzlehttp/psr7": "^1.4",
+                "php": ">=5.5"
+            },
+            "require-dev": {
+                "ext-curl": "*",
+                "phpunit/phpunit": "^4.8.35 || ^5.7 || ^6.4 || ^7.0",
+                "psr/log": "^1.0"
+            },
+            "suggest": {
+                "psr/log": "Required for using the Log middleware"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "6.3-dev"
+                }
+            },
+            "autoload": {
+                "files": [
+                    "src/functions_include.php"
+                ],
+                "psr-4": {
+                    "GuzzleHttp\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                }
+            ],
+            "description": "Guzzle is a PHP HTTP client library",
+            "homepage": "http://guzzlephp.org/",
+            "keywords": [
+                "client",
+                "curl",
+                "framework",
+                "http",
+                "http client",
+                "rest",
+                "web service"
+            ],
+            "time": "2018-04-22T15:46:56+00:00"
+        },
+        {
+            "name": "guzzlehttp/promises",
+            "version": "v1.3.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/guzzle/promises.git",
+                "reference": "a59da6cf61d80060647ff4d3eb2c03a2bc694646"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/guzzle/promises/zipball/a59da6cf61d80060647ff4d3eb2c03a2bc694646",
+                "reference": "a59da6cf61d80060647ff4d3eb2c03a2bc694646",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.5.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^4.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.4-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "GuzzleHttp\\Promise\\": "src/"
+                },
+                "files": [
+                    "src/functions_include.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                }
+            ],
+            "description": "Guzzle promises library",
+            "keywords": [
+                "promise"
+            ],
+            "time": "2016-12-20T10:07:11+00:00"
+        },
+        {
+            "name": "guzzlehttp/psr7",
+            "version": "1.4.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/guzzle/psr7.git",
+                "reference": "f5b8a8512e2b58b0071a7280e39f14f72e05d87c"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/guzzle/psr7/zipball/f5b8a8512e2b58b0071a7280e39f14f72e05d87c",
+                "reference": "f5b8a8512e2b58b0071a7280e39f14f72e05d87c",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.4.0",
+                "psr/http-message": "~1.0"
+            },
+            "provide": {
+                "psr/http-message-implementation": "1.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~4.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.4-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "GuzzleHttp\\Psr7\\": "src/"
+                },
+                "files": [
+                    "src/functions_include.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                },
+                {
+                    "name": "Tobias Schultze",
+                    "homepage": "https://github.com/Tobion"
+                }
+            ],
+            "description": "PSR-7 message implementation that also provides common utility methods",
+            "keywords": [
+                "http",
+                "message",
+                "request",
+                "response",
+                "stream",
+                "uri",
+                "url"
+            ],
+            "time": "2017-03-20T17:10:46+00:00"
+        },
+        {
+            "name": "psr/http-message",
+            "version": "1.0.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/php-fig/http-message.git",
+                "reference": "f6561bf28d520154e4b0ec72be95418abe6d9363"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/php-fig/http-message/zipball/f6561bf28d520154e4b0ec72be95418abe6d9363",
+                "reference": "f6561bf28d520154e4b0ec72be95418abe6d9363",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.0.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Psr\\Http\\Message\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "PHP-FIG",
+                    "homepage": "http://www.php-fig.org/"
+                }
+            ],
+            "description": "Common interface for HTTP messages",
+            "homepage": "https://github.com/php-fig/http-message",
+            "keywords": [
+                "http",
+                "http-message",
+                "psr",
+                "psr-7",
+                "request",
+                "response"
+            ],
+            "time": "2016-08-06T14:39:51+00:00"
+        },
         {
             "name": "vlucas/phpdotenv",
             "version": "v2.5.0",