Abstract the Guzzle dependency to a HttpClient implementation

.gitattributes

@@ -1,5 +1,8 @@
+/.github
 /tests export-ignore
 /.gitattributes export-ignore
 /.gitignore export-ignore
 /.travis.yml export-ignore
+/Makefile
 /phpunit.xml export-ignore
+/scoper.inc.php export-ignore

Makefile

@@ -7,6 +7,7 @@ mollie-api-php.zip:
 	# First, install all dependencies. Then prefix everything with humbug/php-scoper. Finally, we should dump the
 	# autoloader again to update the autoloader with the new classnames.
 	#
+	composer require php-http/guzzle6-adapter
 	composer install --no-dev --no-scripts --no-suggest
 	$(shell composer global config bin-dir --absolute)/php-scoper add-prefix --force
 	composer dump-autoload --working-dir build --classmap-authoritative

README.md

@@ -16,18 +16,18 @@ To use the Mollie API client, the following things are required:
 + Follow [a few steps](https://www.mollie.com/dashboard/?modal=onboarding) to enable payment methods in live mode, and let us handle the rest.
 + PHP >= 5.6
 + Up-to-date OpenSSL (or other SSL/TLS toolkit)
++ An HTTP client which implements the ``php-http/client-implementation``. You can find the available implementations [here](https://packagist.org/providers/php-http/client-implementation). We recommend ``php-http/guzzle6-adapter``.
 
 ## Composer Installation ##
 
-By far the easiest way to install the Mollie API client is to require it with [Composer](http://getcomposer.org/doc/00-intro.md).
+By far the easiest way to install the Mollie API client is to require it with [Composer](http://getcomposer.org/doc/00-intro.md).  
 
-    $ composer require mollie/mollie-api-php:^2.0
+The Mollie client depends on a ``php-http/client-implementation`` so make sure to install a package providing that.
+We suggest using ``php-http/guzzle6-adapter``.
 
-    {
-        "require": {
-            "mollie/mollie-api-php": "^2.0"
-        }
-    }
+```console
+$ composer require mollie/mollie-api-php:^2.1 php-http/guzzle6-adapter:^1.0
+```
 
 The version of the API client corresponds to the version of the API it implements. Check the [notes on migration](https://docs.mollie.com/migrating-v1-to-v2) to see what changes you need to make if you want to start using a newer API version.
 

composer.json

@@ -47,11 +47,17 @@
     "ext-curl": "*",
     "ext-json": "*",
     "ext-openssl": "*",
-    "guzzlehttp/guzzle": "^6.3"
+    "psr/http-message": "^1.0",
+    "php-http/client-implementation": "^1.0",
+    "php-http/discovery": "^1.0",
+    "php-http/message-factory": "^1.0"
   },
   "require-dev": {
+    "eloquent/liberator": "^2.0",
     "phpunit/phpunit": "^5.7|^6.5|^7.1",
-    "eloquent/liberator": "^2.0"
+    "php-http/mock-client": "^1.1",
+    "php-http/message": "^1.6",
+    "guzzlehttp/psr7": "^1.0"
   },
   "autoload": {
     "psr-4": {

src/Endpoints/EndpointAbstract.php

@@ -71,10 +71,9 @@ private function buildQueryString(array $filters)
      */
     protected function rest_create($body, array $filters)
     {
-        try {
-            $encoded = \GuzzleHttp\json_encode($body);
-        } catch (\InvalidArgumentException $e) {
-            throw new ApiException("Error encoding parameters into JSON: '" . $e->getMessage() . "'.");
+        $encoded = json_encode($body);
+        if (JSON_ERROR_NONE !== json_last_error()) {
+            throw new ApiException("Error encoding parameters into JSON: '" . json_last_error_msg() . "'.");
         }
 
         $result = $this->api->performHttpCall(

src/MollieApiClient.php

@@ -2,10 +2,12 @@
 
 namespace Mollie\Api;
 
-use GuzzleHttp\Client;
-use GuzzleHttp\ClientInterface;
-use GuzzleHttp\Exception\GuzzleException;
-use GuzzleHttp\Psr7\Request;
+use Http\Client\Exception\RequestException;
+use Http\Client\HttpClient;
+use Http\Discovery\Exception;
+use Http\Discovery\HttpClientDiscovery;
+use Http\Discovery\MessageFactoryDiscovery;
+use Http\Message\RequestFactory;
 use Mollie\Api\Endpoints\CustomerEndpoint;
 use Mollie\Api\Endpoints\CustomerPaymentsEndpoint;
 use Mollie\Api\Endpoints\InvoiceEndpoint;
@@ -52,10 +54,15 @@ class MollieApiClient
     const HTTP_NO_CONTENT = 204;
 
     /**
-     * @var ClientInterface
+     * @var HttpClient
      */
     protected $httpClient;
 
+    /**
+     * @var RequestFactory
+     */
+    private $requestFactory;
+
     /**
      * @var string
      */
@@ -150,13 +157,25 @@ class MollieApiClient
     protected $lastHttpResponseStatusCode;
 
     /**
-     * @param ClientInterface $httpClient
+     * @param HttpClient $httpClient
+     * @param RequestFactory $requestFactory
      *
      * @throws IncompatiblePlatform
      */
-    public function __construct(ClientInterface $httpClient = null)
+    public function __construct(HttpClient $httpClient = null, RequestFactory $requestFactory = null)
     {
-        $this->httpClient = $httpClient ? $httpClient : new Client();
+        try {
+            $this->httpClient = $httpClient ? $httpClient : HttpClientDiscovery::find();
+            $this->requestFactory = $requestFactory ? $requestFactory : MessageFactoryDiscovery::find();
+        } catch (Exception\NotFoundException $e) {
+            throw new IncompatiblePlatform(
+                'We could not find any http-client-implementation. Install a package providing "php-http/client-implementation". Example: "composer install php-http/guzzle6-adapter".'
+            );
+        } catch (Exception\DiscoveryFailedException $e) {
+            throw new IncompatiblePlatform(
+                'We could not find any http client or message factory. Install a package providing "php-http/client-implementation" and a PSR7 message implementation. Example: "composer install php-http/guzzle6-adapter".'
+            );
+        }
 
         $compatibilityChecker = new CompatibilityChecker();
         $compatibilityChecker->checkCompatibility();
@@ -165,10 +184,9 @@ public function __construct(ClientInterface $httpClient = null)
 
         $this->addVersionString("Mollie/" . self::CLIENT_VERSION);
         $this->addVersionString("PHP/" . phpversion());
-        $this->addVersionString("Guzzle/" . ClientInterface::VERSION);
     }
 
-    public function initializeEndpoints()
+    private function initializeEndpoints()
     {
         $this->payments = new PaymentEndpoint($this);
         $this->methods = new MethodEndpoint($this);
@@ -308,11 +326,11 @@ public function performHttpCallToFullUrl($httpMethod, $url, $httpBody = null)
             $headers['X-Mollie-Client-Info'] = php_uname();
         }
 
-        $request = new Request($httpMethod, $url, $headers, $httpBody);
+        $request = $this->requestFactory->createRequest($httpMethod, $url, $headers, $httpBody);
 
         try {
-            $response = $this->httpClient->send($request, ['http_errors' => false]);
-        } catch (GuzzleException $e) {
+            $response = $this->httpClient->sendRequest($request);
+        } catch (RequestException $e) {
             throw new ApiException($e->getMessage(), $e->getCode(), $e);
         }
 
@@ -369,7 +387,7 @@ private function parseResponseBody(ResponseInterface $response)
 
         return $object;
     }
-    
+
     /**
      * Serialization can be used for caching. Of course doing so can be dangerous but some like to live dangerously.
      *

tests/Mollie/API/Endpoints/BaseEndpointTest.php

@@ -2,62 +2,41 @@
 
 namespace Tests\Mollie\Api\Endpoints;
 
-use GuzzleHttp\Client;
 use GuzzleHttp\Psr7\Request;
 use GuzzleHttp\Psr7\Response;
+use Http\Mock\Client;
 use Mollie\Api\MollieApiClient;
 
 abstract class BaseEndpointTest extends \PHPUnit\Framework\TestCase
 {
     /**
-     * @var Client|\PHPUnit_Framework_MockObject_MockObject
+     * @var Client
      */
-    protected $guzzleClient;
+    protected $httpClient;
+
+    /**
+     * @var
+     */
+    protected $messageFactory;
 
     /**
      * @var MollieApiClient
      */
     protected $apiClient;
 
-    protected function mockApiCall(Request $expectedRequest, Response $response)
+    protected function mockApiCall(Response $response)
     {
-        $this->guzzleClient = $this->createMock(Client::class);
+        $this->httpClient = new Client();
+        $this->httpClient->addResponse($response);
 
-        $this->apiClient = new MollieApiClient($this->guzzleClient);
+        $this->apiClient = new MollieApiClient($this->httpClient);
         $this->apiClient->setApiKey("test_dHar4XY7LxsDOtmnkVtjNVWXLSlXsM");
+    }
 
-        $this->guzzleClient
-            ->expects($this->once())
-            ->method('send')
-            ->with($this->isInstanceOf(Request::class))
-            ->willReturnCallback(function (Request $request) use ($expectedRequest, $response) {
-                $this->assertEquals($expectedRequest->getMethod(), $request->getMethod(), "HTTP method must be identical");
-
-                $this->assertEquals(
-                    $expectedRequest->getUri()->getPath(),
-                    $request->getUri()->getPath(),
-                    "URI path must be identical"
-                );
-
-                $this->assertEquals(
-                    $expectedRequest->getUri()->getQuery(),
-                    $request->getUri()->getQuery(),
-                    'Query string parameters must be identical'
-                );
-
-                $requestBody = $request->getBody()->getContents();
-                $expectedBody = $expectedRequest->getBody()->getContents();
-
-                if (strlen($expectedBody) > 0 && strlen($requestBody) > 0) {
-                    $this->assertJsonStringEqualsJsonString(
-                        $expectedBody,
-                        $requestBody,
-                        "HTTP body must be identical"
-                    );
-                }
-
-                return $response;
-            });
+    protected function assertRequest(Request $expected_request)
+    {
+        $this->assertEquals($expected_request->getMethod(), $this->httpClient->getLastRequest()->getMethod(), "Expected request method should be equal to actual Request method.");
+        $this->assertEquals($expected_request->getUri(), $this->httpClient->getLastRequest()->getUri(), "Expected request Uri should be equal to actual Request Uri.");
     }
 
     protected function copy($array, $object)

tests/Mollie/API/Endpoints/ChargebackEndpointTest.php

@@ -13,12 +13,6 @@ class ChargebackEndpointTest extends BaseEndpointTest
     public function testGetChargebacksOnPaymentResource()
     {
         $this->mockApiCall(
-            new Request(
-                "GET",
-                "/v2/payments/tr_44aKxzEbr8/chargebacks",
-                [],
-                ''
-            ),
             new Response(
                 201,
                 [],
@@ -92,6 +86,13 @@ public function testGetChargebacksOnPaymentResource()
 
         $chargebacks = $this->getPayment()->chargebacks();
 
+        $this->assertRequest(new Request(
+            "GET",
+            "https://api.mollie.com/v2/payments/tr_44aKxzEbr8/chargebacks",
+            [],
+            ''
+        ));
+
         $this->assertInstanceOf(ChargebackCollection::class, $chargebacks);
         $this->assertEquals(2, $chargebacks->count);
         $this->assertCount(2, $chargebacks);

tests/Mollie/API/Endpoints/CustomerEndpointTest.php

@@ -12,7 +12,6 @@ class CustomerEndpointTest extends BaseEndpointTest
     public function testCreateWorks()
     {
         $this->mockApiCall(
-            new Request('POST', '/v2/customers'),
             new Response(
                 200,
                 [],
@@ -42,6 +41,11 @@ public function testCreateWorks()
             "email" => "johndoe@example.org"
         ]);
 
+        $this->assertRequest(new Request(
+            'POST',
+            'https://api.mollie.com/v2/customers'
+        ));
+
         $this->assertInstanceOf(Customer::class, $customer);
         $this->assertEquals("customer", $customer->resource);
         $this->assertEquals("cst_FhQJRw4s2n", $customer->id);
@@ -60,7 +64,6 @@ public function testCreateWorks()
     public function testGetWorks()
     {
         $this->mockApiCall(
-            new Request('GET', '/v2/customers/cst_FhQJRw4s2n'),
             new Response(
                 200,
                 [],
@@ -87,6 +90,11 @@ public function testGetWorks()
         /** @var Customer $customer */
         $customer = $this->apiClient->customers->get("cst_FhQJRw4s2n");
 
+        $this->assertRequest(new Request(
+            'GET',
+            'https://api.mollie.com/v2/customers/cst_FhQJRw4s2n'
+        ));
+
         $this->assertInstanceOf(Customer::class, $customer);
         $this->assertEquals("customer", $customer->resource);
         $this->assertEquals("cst_FhQJRw4s2n", $customer->id);
@@ -105,7 +113,6 @@ public function testGetWorks()
     public function testListWorks()
     {
         $this->mockApiCall(
-            new Request('GET', '/v2/customers'),
             new Response(
                 200,
                 [],
@@ -145,6 +152,11 @@ public function testListWorks()
         /** @var Customer $customer */
         $customers = $this->apiClient->customers->page();
 
+        $this->assertRequest(new Request(
+            'GET',
+            'https://api.mollie.com/v2/customers'
+        ));
+
         $this->assertInstanceOf(CustomerCollection::class, $customers);
 
         $documentationLink = (object)["href" => "https://docs.mollie.com/reference/v2/customers-api/list-customers", "type" => "text/html"];
@@ -167,7 +179,6 @@ public function testUpdateWorks()
         $expectedEmail = 'kaas.broodje@gmail.com';
 
         $this->mockApiCall(
-            new Request('PATCH', '/v2/customers/cst_FhQJRw4s2n'),
             new Response(
                 200,
                 [],
@@ -197,6 +208,8 @@ public function testUpdateWorks()
 
         $updatedCustomer = $customer->update();
 
+        $this->assertRequest(new Request('PATCH', 'https://api.mollie.com/v2/customers/cst_FhQJRw4s2n'));
+
         $this->assertEquals($expectedName, $updatedCustomer->name);
         $this->assertEquals($expectedEmail, $updatedCustomer->email);
     }
@@ -218,7 +231,7 @@ private function getCustomer()
             "createdAt": "2018-04-19T08:49:01+00:00",
             "_links": {
                 "self": {
-                    "href": "http://api.mollie.test/v2/customers/cst_FhQJRw4s2n",
+                    "href": "https://api.mollie.com/v2/customers/cst_FhQJRw4s2n",
                     "type": "application/hal+json"
                 },
                 "documentation": {