25 files changed, 1062 insertions, 0 deletions

diff --git a/vendor/paypal/paypalhttp/.gitattributes b/vendor/paypal/paypalhttp/.gitattributes
new file mode 100644
index 0000000..ec6c2f5
--- /dev/null
+++ b/vendor/paypal/paypalhttp/.gitattributes
@@ -0,0 +1,7 @@
+tests/ export-ignore
+.idea/ export-ignore
+.github/ export-ignore
+.releasinator.rb export-ignore
+Gemfile export-ignore
+Gemfile.lock export-ignore
+
diff --git a/vendor/paypal/paypalhttp/.gitignore b/vendor/paypal/paypalhttp/.gitignore
new file mode 100644
index 0000000..2efb91f
--- /dev/null
+++ b/vendor/paypal/paypalhttp/.gitignore
@@ -0,0 +1,32 @@
+.DS_Store
+/vendor/
+composer.phar
+composer.lock
+
+# User-specific stuff:
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/dictionaries
+
+.idea/codeStyles/Project.xml
+.idea/codeStyles/codeStyleConfig.xml
+.idea/*
+
+# Sensitive or high-churn files:
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.xml
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+
+## File-based project format:
+*.iws
+.idea/*.iml
+.idea/vcs.xml
+.idea/php.xml
+.idea/php-test-framework.xml
+.idea/modules.xml
+__files/*
+mappings/*
diff --git a/vendor/paypal/paypalhttp/.travis.yml b/vendor/paypal/paypalhttp/.travis.yml
new file mode 100644
index 0000000..4fddbb9
--- /dev/null
+++ b/vendor/paypal/paypalhttp/.travis.yml
@@ -0,0 +1,16 @@
+sudo: false
+language: php
+php:
+- 5.6
+- 7.0
+- 7.1
+- hhvm
+matrix:
+  allow_failures:
+  - php: hhvm
+  fast_finish: true
+before_script:
+- composer self-update
+- composer install --dev
+script:
+- vendor/bin/phpunit
diff --git a/vendor/paypal/paypalhttp/CHANGELOG.md b/vendor/paypal/paypalhttp/CHANGELOG.md
new file mode 100644
index 0000000..f55b907
--- /dev/null
+++ b/vendor/paypal/paypalhttp/CHANGELOG.md
@@ -0,0 +1,2 @@
+## 1.0.0
+- First release
diff --git a/vendor/paypal/paypalhttp/CONTRIBUTING.md b/vendor/paypal/paypalhttp/CONTRIBUTING.md
new file mode 100644
index 0000000..3810a58
--- /dev/null
+++ b/vendor/paypal/paypalhttp/CONTRIBUTING.md
@@ -0,0 +1,10 @@
+# Contribute to the PayPal PHP HttpClient
+
+### *Pull requests are welcome!*
+
+General Guidelines
+------------------
+
+* **Code style.** Please follow local code style. Ask if you're unsure. 
+* **No warnings.** All generated code must compile without warnings.
+
diff --git a/vendor/paypal/paypalhttp/LICENSE b/vendor/paypal/paypalhttp/LICENSE
new file mode 100644
index 0000000..c689d74
--- /dev/null
+++ b/vendor/paypal/paypalhttp/LICENSE
@@ -0,0 +1,23 @@
+Copyright (c) 2009-2016 PayPal, Inc.
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated documentation
+files (the "Software"), to deal in the Software without
+restriction, including without limitation the rights to use,
+copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
diff --git a/vendor/paypal/paypalhttp/README.md b/vendor/paypal/paypalhttp/README.md
new file mode 100644
index 0000000..c4bc958
--- /dev/null
+++ b/vendor/paypal/paypalhttp/README.md
@@ -0,0 +1,76 @@
+## PayPal HttpClient
+
+PayPalHttp is a generic HTTP Client.
+
+In it's simplest form, an [`HttpClient`](lib/PayPalHttp/HttpClient.php) exposes an `execute` method which takes an [HTTP request](lib/PayPalHttp/HttpRequest.php), executes it against the domain described in an [Environment](lib/PayPalHttp/Environment.php), and returns an [HTTP response](lib/PayPalHttp/HttpResponse.php).
+
+### Environment
+
+An [`Environment`](./lib/PayPalHttp/environment.rb) describes a domain that hosts a REST API, against which an `HttpClient` will make requests. `Environment` is a simple interface that wraps one method, `baseUrl`.
+
+```php
+$env = new Environment('https://example.com');
+```
+
+### Requests
+
+HTTP requests contain all the information needed to make an HTTP request against the REST API. Specifically, one request describes a path, a verb, any path/query/form parameters, headers, attached files for upload, and body data.
+
+### Responses
+
+HTTP responses contain information returned by a server in response to a request as described above. They are simple objects which contain a status code, headers, and any data returned by the server.
+
+```php
+$request = new HttpRequest("/path", "GET");
+$request->body[] = "some data";
+
+$response = $client->execute($req);
+
+$statusCode = $response->statusCode;
+$headers = $response->headers;
+$data = $response->result;
+```
+
+### Injectors
+
+Injectors are blocks that can be used for executing arbitrary pre-flight logic, such as modifying a request or logging data. Injectors are attached to an `HttpClient` using the `addInjector` method.
+
+The `HttpClient` executes its injectors in a first-in, first-out order, before each request.
+
+```php
+class LogInjector implements Injector
+{
+    public function inject($httpRequest)
+    {
+        // Do some logging here
+    }
+}
+
+$logInjector = new LogInjector();
+$client = new HttpClient($environment);
+$client->addInjector($logInjector);
+...
+```
+
+### Error Handling
+
+`HttpClient#execute` may throw an `Exception` if something went wrong during the course of execution. If the server returned a non-200 response, [IOException](lib/PayPalHttp/IOException.php) will be thrown, that will contain a status code and headers you can use for debugging.
+
+```php
+try
+{
+    $client->execute($req);
+}
+catch (HttpException $e)
+{
+    $statusCode = $e->response->statusCode;
+    $headers = $e->response->headers;
+    $body = $e->response->result;
+}
+```
+
+## License
+PayPalHttp-PHP is open source and available under the MIT license. See the [LICENSE](./LICENSE) file for more information.
+
+## Contributing
+Pull requests and issues are welcome. Please see [CONTRIBUTING.md](./CONTRIBUTING.md) for more details.
diff --git a/vendor/paypal/paypalhttp/Rakefile b/vendor/paypal/paypalhttp/Rakefile
new file mode 100644
index 0000000..33a443c
--- /dev/null
+++ b/vendor/paypal/paypalhttp/Rakefile
@@ -0,0 +1,2 @@
+spec = Gem::Specification.find_by_name 'releasinator'
+load "#{spec.gem_dir}/lib/tasks/releasinator.rake"
diff --git a/vendor/paypal/paypalhttp/composer.json b/vendor/paypal/paypalhttp/composer.json
new file mode 100644
index 0000000..05728a3
--- /dev/null
+++ b/vendor/paypal/paypalhttp/composer.json
@@ -0,0 +1,23 @@
+{
+    "name": "paypal/paypalhttp",
+    "type": "library",
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "PayPal",
+            "homepage": "https://github.com/paypal/paypalhttp_php/contributors"
+        }
+    ],
+    "require": {
+        "ext-curl": "*"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^5.7",
+        "wiremock-php/wiremock-php": "1.43.2"
+    },
+    "autoload": {
+        "psr-4": {
+            "PayPalHttp\\": "lib/PayPalHttp"
+        }
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Curl.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Curl.php
new file mode 100644
index 0000000..08e6eaf
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Curl.php
@@ -0,0 +1,57 @@
+<?php
+
+namespace PayPalHttp;
+
+/**
+ * Class Curl
+ * @package PayPalHttp
+ *
+ * Curl wrapper used by HttpClient to make curl requests.
+ * @see HttpClient
+ */
+class Curl
+{
+    protected $curl;
+
+    public function __construct($curl = NULL)
+    {
+
+        if (is_null($curl))
+        {
+            $curl = curl_init();
+        }
+        $this->curl = $curl;
+    }
+
+    public function setOpt($option, $value)
+    {
+        curl_setopt($this->curl, $option, $value);
+        return $this;
+    }
+
+    public function close()
+    {
+        curl_close($this->curl);
+        return $this;
+    }
+
+    public function exec()
+    {
+        return curl_exec($this->curl);
+    }
+
+    public function errNo()
+    {
+        return curl_errno($this->curl);
+    }
+
+    public function getInfo($option)
+    {
+        return curl_getinfo($this->curl, $option);
+    }
+
+    public function error()
+    {
+        return curl_error($this->curl);
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Encoder.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Encoder.php
new file mode 100644
index 0000000..b7158a7
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Encoder.php
@@ -0,0 +1,114 @@
+<?php
+
+namespace PayPalHttp;
+
+use PayPalHttp\Serializer\Form;
+use PayPalHttp\Serializer\Json;
+use PayPalHttp\Serializer\Multipart;
+use PayPalHttp\Serializer\Text;
+
+/**
+ * Class Encoder
+ * @package PayPalHttp
+ *
+ * Encoding class for serializing and deserializing request/response.
+ */
+class Encoder
+{
+    private $serializers = [];
+
+    function __construct()
+    {
+        $this->serializers[] = new Json();
+        $this->serializers[] = new Text();
+        $this->serializers[] = new Multipart();
+        $this->serializers[] = new Form();
+    }
+
+
+
+    public function serializeRequest(HttpRequest $request)
+    {
+        if (!array_key_exists('content-type', $request->headers)) {
+            $message = "HttpRequest does not have Content-Type header set";
+            echo $message;
+            throw new \Exception($message);
+        }
+
+        $contentType = $request->headers['content-type'];
+        /** @var Serializer $serializer */
+        $serializer = $this->serializer($contentType);
+
+        if (is_null($serializer)) {
+            $message = sprintf("Unable to serialize request with Content-Type: %s. Supported encodings are: %s", $contentType, implode(", ", $this->supportedEncodings()));
+            echo $message;
+            throw new \Exception($message);
+        }
+
+        if (!(is_string($request->body) || is_array($request->body))) {
+            $message = "Body must be either string or array";
+            echo $message;
+            throw new \Exception($message);
+        }
+
+        $serialized = $serializer->encode($request);
+
+        if (array_key_exists("content-encoding", $request->headers) && $request->headers["content-encoding"] === "gzip") {
+            $serialized = gzencode($serialized);
+        }
+        return $serialized;
+    }
+
+
+    public function deserializeResponse($responseBody, $headers)
+    {
+
+        if (!array_key_exists('content-type', $headers)) {
+            $message = "HTTP response does not have Content-Type header set";
+            echo $message;
+            throw new \Exception($message);
+        }
+
+        $contentType = $headers['content-type'];
+        /** @var Serializer $serializer */
+        $serializer = $this->serializer($contentType);
+
+        if (is_null($serializer)) {
+            throw new \Exception(sprintf("Unable to deserialize response with Content-Type: %s. Supported encodings are: %s", $contentType, implode(", ", $this->supportedEncodings())));
+        }
+
+        if (array_key_exists("content-encoding", $headers) && $headers["content-encoding"] === "gzip") {
+            $responseBody = gzdecode($responseBody);
+        }
+
+        return $serializer->decode($responseBody);
+    }
+
+    private function serializer($contentType)
+    {
+        /** @var Serializer $serializer */
+        foreach ($this->serializers as $serializer) {
+            try {
+                if (preg_match($serializer->contentType(), $contentType) == 1) {
+                    return $serializer;
+                }
+            } catch (\Exception $ex) {
+                $message = sprintf("Error while checking content type of %s: %s", get_class($serializer), $ex->getMessage());
+                echo $message;
+                throw new \Exception($message, $ex->getCode(), $ex);
+            }
+        }
+
+        return NULL;
+    }
+
+    private function supportedEncodings()
+    {
+        $values = [];
+        /** @var Serializer $serializer */
+        foreach ($this->serializers as $serializer) {
+            $values[] = $serializer->contentType();
+        }
+        return $values;
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Environment.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Environment.php
new file mode 100644
index 0000000..4eb0ce0
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Environment.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace PayPalHttp;
+
+/**
+ * Interface Environment
+ * @package PayPalHttp
+ *
+ * Describes a domain that hosts a REST API, against which an HttpClient will make requests.
+ * @see HttpClient
+ */
+interface Environment
+{
+    /**
+     * @return string
+     */
+    public function baseUrl();
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpClient.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpClient.php
new file mode 100644
index 0000000..dbbdb79
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpClient.php
@@ -0,0 +1,231 @@
+<?php
+
+namespace PayPalHttp;
+
+/**
+ * Class HttpClient
+ * @package PayPalHttp
+ *
+ * Client used to make HTTP requests.
+ */
+class HttpClient
+{
+    /**
+     * @var Environment
+     */
+    public $environment;
+
+    /**
+     * @var Injector[]
+     */
+    public $injectors = [];
+
+    /**
+     * @var Encoder
+     */
+    public $encoder;
+
+    /**
+     * HttpClient constructor. Pass the environment you wish to make calls to.
+     *
+     * @param $environment Environment
+     * @see Environment
+     */
+    function __construct(Environment $environment)
+    {
+        $this->environment = $environment;
+        $this->encoder = new Encoder();
+        $this->curlCls = Curl::class;
+    }
+
+    /**
+     * Injectors are blocks that can be used for executing arbitrary pre-flight logic, such as modifying a request or logging data.
+     * Executed in first-in first-out order.
+     *
+     * @param Injector $inj
+     */
+    public function addInjector(Injector $inj)
+    {
+        $this->injectors[] = $inj;
+    }
+
+    /**
+     * The method that takes an HTTP request, serializes the request, makes a call to given environment, and deserialize response
+     *
+     * @param $httpRequest HttpRequest
+     * @return HttpResponse
+     */
+    public function execute(HttpRequest $httpRequest)
+    {
+        $requestCpy = clone $httpRequest;
+        $curl = new Curl();
+
+        foreach ($this->injectors as $inj) {
+            $inj->inject($requestCpy);
+        }
+
+        $url = $this->environment->baseUrl() . $requestCpy->path;
+        $formattedHeaders = $this->prepareHeaders($requestCpy->headers);
+        if (!array_key_exists("user-agent", $formattedHeaders)) {
+            $requestCpy->headers["user-agent"] = $this->userAgent();
+        }
+
+        $body = "";
+        if (!is_null($requestCpy->body)) {
+            $rawHeaders = $requestCpy->headers;
+            $requestCpy->headers = $formattedHeaders;
+            $body = $this->encoder->serializeRequest($requestCpy);
+            $requestCpy->headers = $this->mapHeaders($rawHeaders,$requestCpy->headers);
+        }
+
+        $curl->setOpt(CURLOPT_URL, $url);
+        $curl->setOpt(CURLOPT_CUSTOMREQUEST, $requestCpy->verb);
+        $curl->setOpt(CURLOPT_HTTPHEADER, $this->serializeHeaders($requestCpy->headers));
+        $curl->setOpt(CURLOPT_RETURNTRANSFER, 1);
+        $curl->setOpt(CURLOPT_HEADER, 0);
+
+        if (!is_null($requestCpy->body)) {
+            $curl->setOpt(CURLOPT_POSTFIELDS, $body);
+        }
+
+        if (strpos($this->environment->baseUrl(), "https://") === 0) {
+            $curl->setOpt(CURLOPT_SSL_VERIFYPEER, true);
+            $curl->setOpt(CURLOPT_SSL_VERIFYHOST, 2);
+        }
+
+        if ($caCertPath = $this->getCACertFilePath()) {
+            $curl->setOpt(CURLOPT_CAINFO, $caCertPath);
+        }
+
+        $response = $this->parseResponse($curl);
+        $curl->close();
+
+        return $response;
+    }
+
+    /**
+     * Returns an array representing headers with their keys
+     * to be lower case
+     * @param $headers
+     * @return array
+     */
+    public function prepareHeaders($headers){
+        return array_change_key_case($headers);
+    }
+
+    /**
+     * Returns an array representing headers with their key in
+     * original cases and updated values
+     * @param $rawHeaders
+     * @param $formattedHeaders
+     * @return array
+     */
+    public function mapHeaders($rawHeaders, $formattedHeaders){
+        $rawHeadersKey = array_keys($rawHeaders);
+        foreach ($rawHeadersKey as $array_key) {
+            if(array_key_exists(strtolower($array_key), $formattedHeaders)){
+                $rawHeaders[$array_key] = $formattedHeaders[strtolower($array_key)];
+            }
+        }
+        return $rawHeaders;
+    }
+
+    /**
+     * Returns default user-agent
+     *
+     * @return string
+     */
+    public function userAgent()
+    {
+        return "PayPalHttp-PHP HTTP/1.1";
+    }
+
+    /**
+     * Return the filepath to your custom CA Cert if needed.
+     * @return string
+     */
+    protected function getCACertFilePath()
+    {
+        return null;
+    }
+
+    protected function setCurl(Curl $curl)
+    {
+        $this->curl = $curl;
+    }
+
+    protected function setEncoder(Encoder $encoder)
+    {
+        $this->encoder = $encoder;
+    }
+
+    private function serializeHeaders($headers)
+    {
+        $headerArray = [];
+        if ($headers) {
+            foreach ($headers as $key => $val) {
+                $headerArray[] = $key . ": " . $val;
+            }
+        }
+
+        return $headerArray;
+    }
+
+    private function parseResponse($curl)
+    {
+        $headers = [];
+        $curl->setOpt(CURLOPT_HEADERFUNCTION,
+            function($curl, $header) use (&$headers)
+            {
+                $len = strlen($header);
+
+                $k = "";
+                $v = "";
+
+                $this->deserializeHeader($header, $k, $v);
+                $headers[$k] = $v;
+
+                return $len;
+            });
+
+        $responseData = $curl->exec();
+        $statusCode = $curl->getInfo(CURLINFO_HTTP_CODE);
+        $errorCode = $curl->errNo();
+        $error = $curl->error();
+
+        if ($errorCode > 0) {
+            throw new IOException($error, $errorCode);
+        }
+
+        $body = $responseData;
+
+        if ($statusCode >= 200 && $statusCode < 300) {
+            $responseBody = NULL;
+
+            if (!empty($body)) {
+                $responseBody = $this->encoder->deserializeResponse($body, $this->prepareHeaders($headers));
+            }
+
+            return new HttpResponse(
+                $errorCode === 0 ? $statusCode : $errorCode,
+                $responseBody,
+                $headers
+            );
+        } else {
+            throw new HttpException($body, $statusCode, $headers);
+        }
+    }
+
+    private function deserializeHeader($header, &$key, &$value)
+    {
+        if (strlen($header) > 0) {
+            if (empty($header) || strpos($header, ':') === false) {
+                return NULL;
+            }
+
+            list($k, $v) = explode(":", $header);
+            $key = trim($k);
+            $value = trim($v);
+        }
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpException.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpException.php
new file mode 100644
index 0000000..5f4d2db
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpException.php
@@ -0,0 +1,23 @@
+<?php
+
+namespace PayPalHttp;
+
+class HttpException extends IOException
+{
+    /**
+     * @var statusCode
+     */
+    public $statusCode;
+
+    public $headers;
+
+    /**
+     * @param string $response
+     */
+    public function __construct($message, $statusCode, $headers)
+    {
+        parent::__construct($message);
+        $this->statusCode = $statusCode;
+        $this->headers = $headers;
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpRequest.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpRequest.php
new file mode 100644
index 0000000..89b7480
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpRequest.php
@@ -0,0 +1,42 @@
+<?php
+
+namespace PayPalHttp;
+
+/**
+ * Class HttpRequest
+ * @package PayPalHttp
+ *
+ * Request object that holds all the necessary information required by HTTPClient
+ *
+ * @see HttpClient
+ */
+class HttpRequest
+{
+    /**
+     * @var string
+     */
+    public $path;
+
+    /**
+     * @var array | string
+     */
+    public $body;
+
+    /**
+     * @var string
+     */
+    public $verb;
+
+    /**
+     * @var array
+     */
+    public $headers;
+
+    function __construct($path, $verb)
+    {
+        $this->path = $path;
+        $this->verb = $verb;
+        $this->body = NULL;
+        $this->headers = [];
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpResponse.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpResponse.php
new file mode 100644
index 0000000..ef8fb35
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/HttpResponse.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace PayPalHttp;
+
+/**
+ * Class HttpResponse
+ * @package PayPalHttp
+ *
+ * Object that holds your response details
+ */
+class HttpResponse
+{
+    /**
+     * @var integer
+     */
+    public $statusCode;
+
+    /**
+     * @var array | string
+     */
+    public $result;
+
+    /**
+     * @var array
+     */
+    public $headers;
+
+    public function __construct($statusCode, $body, $headers)
+    {
+        $this->statusCode = $statusCode;
+        $this->headers = $headers;
+        $this->result = $body;
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/IOException.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/IOException.php
new file mode 100644
index 0000000..7bfc91c
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/IOException.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace PayPalHttp;
+
+use Throwable;
+
+class IOException extends \Exception
+{
+    public function __construct($message = "", $code = 0, Throwable $previous = null)
+    {
+        parent::__construct($message, $code, $previous);
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Injector.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Injector.php
new file mode 100644
index 0000000..3ae23c7
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Injector.php
@@ -0,0 +1,19 @@
+<?php
+
+namespace PayPalHttp;
+
+/**
+ * Interface Injector
+ * @package PayPalHttp
+ *
+ * Interface that can be implemented to apply injectors to Http client.
+ *
+ * @see HttpClient
+ */
+interface Injector
+{
+    /**
+     * @param $httpRequest HttpRequest
+     */
+    public function inject($httpRequest);
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer.php
new file mode 100644
index 0000000..2edcfe2
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer.php
@@ -0,0 +1,29 @@
+<?php
+
+namespace PayPalHttp;
+
+/**
+ * Interface Serializer
+ * @package PayPalHttp
+ *
+ * Used to implement different serializers for different content types
+ */
+interface Serializer
+{
+    /**
+     * @return string Regex that matches the content type it supports.
+     */
+    public function contentType();
+
+    /**
+     * @param HttpRequest $request
+     * @return string representation of your data after being serialized.
+     */
+    public function encode(HttpRequest $request);
+
+    /**
+     * @param $body
+     * @return mixed object/string representing the de-serialized response body.
+     */
+    public function decode($body);
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Form.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Form.php
new file mode 100644
index 0000000..bead9d3
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Form.php
@@ -0,0 +1,46 @@
+<?php
+
+namespace PayPalHttp\Serializer;
+
+use PayPalHttp\HttpRequest;
+use PayPalHttp\Serializer;
+
+class Form implements Serializer
+{
+    /**
+     * @return string Regex that matches the content type it supports.
+     */
+    public function contentType()
+    {
+        return "/^application\/x-www-form-urlencoded$/";
+    }
+
+    /**
+     * @param HttpRequest $request
+     * @return string representation of your data after being serialized.
+     */
+    public function encode(HttpRequest $request)
+    {
+        if (!is_array($request->body) || !$this->isAssociative($request->body))
+        {
+            throw new \Exception("HttpRequest body must be an associative array when Content-Type is: " . $request->headers["Content-Type"]);
+        }
+
+        return http_build_query($request->body);
+    }
+
+    /**
+     * @param $body
+     * @return mixed
+     * @throws \Exception as multipart does not support deserialization.
+     */
+    public function decode($body)
+    {
+        throw new \Exception("CurlSupported does not support deserialization");
+    }
+
+    private function isAssociative(array $array)
+    {
+        return array_values($array) !== $array;
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/FormPart.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/FormPart.php
new file mode 100644
index 0000000..3779a9b
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/FormPart.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace PayPalHttp\Serializer;
+
+class FormPart
+{
+    private $value;
+    private $headers;
+
+    public function __construct($value, $headers)
+    {
+        $this->value = $value;
+        $this->headers = array_merge([], $headers);
+    }
+
+    public function getValue()
+    {
+        return $this->value;
+    }
+
+    public function getHeaders()
+    {
+        return $this->headers;
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Json.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Json.php
new file mode 100644
index 0000000..3f66314
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Json.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace PayPalHttp\Serializer;
+
+use PayPalHttp\HttpRequest;
+use PayPalHttp\Serializer;
+
+/**
+ * Class Json
+ * @package PayPalHttp\Serializer
+ *
+ * Serializer for JSON content types.
+ */
+class Json implements Serializer
+{
+
+    public function contentType()
+    {
+        return "/^application\\/json/";
+    }
+
+    public function encode(HttpRequest $request)
+    {
+        $body = $request->body;
+        if (is_string($body)) {
+            return $body;
+        }
+        if (is_array($body)) {
+            return json_encode($body);
+        }
+        throw new \Exception("Cannot serialize data. Unknown type");
+    }
+
+    public function decode($data)
+    {
+        return json_decode($data);
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Multipart.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Multipart.php
new file mode 100644
index 0000000..a420205
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Multipart.php
@@ -0,0 +1,134 @@
+<?php
+
+namespace PayPalHttp\Serializer;
+
+use finfo;
+use PayPalHttp\HttpRequest;
+use PayPalHttp\Serializer;
+use PayPalHttp\Encoder;
+use PayPalHttp\Serializer\FormPart;
+
+/**
+ * Class Multipart
+ * @package PayPalHttp\Serializer
+ *
+ * Serializer for multipart.
+ */
+class Multipart implements Serializer
+{
+    const LINEFEED = "\r\n";
+
+    public function contentType()
+    {
+        return "/^multipart\/.*$/";
+    }
+
+    public function encode(HttpRequest $request)
+    {
+        if (!is_array($request->body) || !$this->isAssociative($request->body))
+        {
+            throw new \Exception("HttpRequest body must be an associative array when Content-Type is: " . $request->headers["content-type"]);
+        }
+        $boundary = "---------------------" . md5(mt_rand() . microtime());
+        $contentTypeHeader = $request->headers["content-type"];
+        $request->headers["content-type"] = "{$contentTypeHeader}; boundary={$boundary}";
+
+        $value_params = [];
+        $file_params = [];
+
+        $disallow = ["\0", "\"", "\r", "\n"];
+
+        $body = [];
+
+        foreach ($request->body as $k => $v) {
+            $k = str_replace($disallow, "_", $k);
+            if (is_resource($v)) {
+                $file_params[] = $this->prepareFilePart($k, $v, $boundary);
+            } else if ($v instanceof FormPart) {
+                $value_params[] = $this->prepareFormPart($k, $v, $boundary);
+            } else {
+                $value_params[] = $this->prepareFormField($k, $v, $boundary);
+            }
+        }
+
+        $body = array_merge($value_params, $file_params);
+
+        // add boundary for each parameters
+        array_walk($body, function (&$part) use ($boundary) {
+            $part = "--{$boundary}" . self::LINEFEED . "{$part}";
+        });
+
+        // add final boundary
+        $body[] = "--{$boundary}--";
+        $body[] = "";
+
+        return implode(self::LINEFEED, $body);
+    }
+
+    public function decode($data)
+    {
+        throw new \Exception("Multipart does not support deserialization");
+    }
+
+    private function isAssociative(array $array)
+    {
+        return array_values($array) !== $array;
+    }
+
+    private function prepareFormField($partName, $value, $boundary)
+    {
+        return implode(self::LINEFEED, [
+            "Content-Disposition: form-data; name=\"{$partName}\"",
+            "",
+            filter_var($value),
+        ]);
+    }
+
+    private function prepareFilePart($partName, $file, $boundary)
+    {
+        $fileInfo = new finfo(FILEINFO_MIME_TYPE);
+        $filePath = stream_get_meta_data($file)['uri'];
+        $data = file_get_contents($filePath);
+        $mimeType = $fileInfo->buffer($data);
+
+        $splitFilePath = explode(DIRECTORY_SEPARATOR, $filePath);
+        $filePath = end($splitFilePath);
+        $disallow = ["\0", "\"", "\r", "\n"];
+        $filePath = str_replace($disallow, "_", $filePath);
+        return implode(self::LINEFEED, [
+            "Content-Disposition: form-data; name=\"{$partName}\"; filename=\"{$filePath}\"",
+            "Content-Type: {$mimeType}",
+            "",
+            $data,
+        ]);
+    }
+
+    private function prepareFormPart($partName, $formPart, $boundary)
+    {
+        $contentDisposition = "Content-Disposition: form-data; name=\"{$partName}\"";
+
+        $partHeaders = $formPart->getHeaders();
+        $formattedheaders = array_change_key_case($partHeaders);
+        if (array_key_exists("content-type", $formattedheaders)) {
+            if ($formattedheaders["content-type"] === "application/json") {
+                $contentDisposition .= "; filename=\"{$partName}.json\"";
+            }
+            $tempRequest = new HttpRequest('/', 'POST');
+            $tempRequest->headers = $formattedheaders;
+            $tempRequest->body = $formPart->getValue();
+            $encoder = new Encoder();
+            $partValue = $encoder->serializeRequest($tempRequest);
+        } else {
+            $partValue = $formPart->getValue();
+        }
+
+        $finalPartHeaders = [];
+        foreach ($partHeaders as $k => $v) {
+            $finalPartHeaders[] = "{$k}: {$v}";
+        }
+
+        $body = array_merge([$contentDisposition], $finalPartHeaders, [""], [$partValue]);
+
+        return implode(self::LINEFEED, $body);
+    }
+}
diff --git a/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Text.php b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Text.php
new file mode 100644
index 0000000..e2ce0ca
--- /dev/null
+++ b/vendor/paypal/paypalhttp/lib/PayPalHttp/Serializer/Text.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace PayPalHttp\Serializer;
+
+use PayPalHttp\HttpRequest;
+use PayPalHttp\Serializer;
+
+/**
+ * Class Text
+ * @package PayPalHttp\Serializer
+ *
+ * Serializer for Text content types.
+ */
+class Text implements Serializer
+{
+
+    public function contentType()
+    {
+        return "/^text\\/.*/";
+    }
+
+    public function encode(HttpRequest $request)
+    {
+        $body = $request->body;
+        if (is_string($body)) {
+            return $body;
+        }
+        if (is_array($body)) {
+            return json_encode($body);
+        }
+        return implode(" ", $body);
+    }
+
+    public function decode($data)
+    {
+        return $data;
+    }
+}
diff --git a/vendor/paypal/paypalhttp/phpunit.xml b/vendor/paypal/paypalhttp/phpunit.xml
new file mode 100644
index 0000000..ea84278
--- /dev/null
+++ b/vendor/paypal/paypalhttp/phpunit.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<phpunit bootstrap="./vendor/autoload.php">
+
+    <testsuites>
+        <testsuite name="unit">
+            <directory>./tests/unit</directory>
+        </testsuite>
+    </testsuites>
+
+</phpunit>