Introduce ResponseParsingException and throw this exception in …

src/Provider/AbstractProvider.php

@@ -22,6 +22,7 @@
 use League\OAuth2\Client\OptionProvider\OptionProviderInterface;
 use League\OAuth2\Client\OptionProvider\PostAuthOptionProvider;
 use League\OAuth2\Client\Provider\Exception\IdentityProviderException;
+use League\OAuth2\Client\Provider\Exception\ResponseParsingException;
 use League\OAuth2\Client\Token\AccessToken;
 use League\OAuth2\Client\Token\AccessTokenInterface;
 use League\OAuth2\Client\Tool\ArrayAccessorTrait;
@@ -98,6 +99,15 @@ abstract class AbstractProvider
      */
     protected $optionProvider;
 
+    /**
+     * If a response body cannot be parsed, a value true of this flag will allow
+     * the response parser to throw a ResponseParsingException containing
+     * the response and the body.
+     *
+     * @var bool
+     */
+    protected $mayThrowResponseParsingException = false;
+
     /**
      * Constructs an OAuth 2.0 service provider.
      *
@@ -520,6 +530,8 @@ protected function getAccessTokenRequest(array $params)
      * @param  mixed $grant
      * @param  array $options
      * @throws IdentityProviderException
+     * @throws ResponseParsingException if the flag $mayThrowResponseParsingException is true and
+     *                                  response body cannot be parsed.
      * @return AccessTokenInterface
      */
     public function getAccessToken($grant, array $options = [])
@@ -613,6 +625,8 @@ public function getResponse(RequestInterface $request)
      *
      * @param  RequestInterface $request
      * @throws IdentityProviderException
+     * @throws ResponseParsingException if the flag $mayThrowResponseParsingException is true and
+     *                                  response body cannot be parsed.
      * @return mixed
      */
     public function getParsedResponse(RequestInterface $request)
@@ -666,8 +680,10 @@ protected function getContentType(ResponseInterface $response)
      * Parses the response according to its content-type header.
      *
      * @throws UnexpectedValueException
+     * @throws ResponseParsingException if the flag $mayThrowResponseParsingException is true and
+     *                                  response body cannot be parsed.
      * @param  ResponseInterface $response
-     * @return array
+     * @return array|string
      */
     protected function parseResponse(ResponseInterface $response)
     {
@@ -686,18 +702,26 @@ protected function parseResponse(ResponseInterface $response)
             return $this->parseJson($content);
         } catch (UnexpectedValueException $e) {
             if (strpos($type, 'json') !== false) {
-                throw $e;
+                throw $this->mayThrowResponseParsingException
+                    ? new ResponseParsingException($response, $content, $e->getMessage(), $e->getCode())
+                    : $e;
             }
 
-            if ($response->getStatusCode() == 500) {
-                throw new UnexpectedValueException(
-                    'An OAuth server error was encountered that did not contain a JSON body',
-                    0,
-                    $e
-                );
+            // for any other content types
+            if ($this->mayThrowResponseParsingException) {
+                // let the calling function decide what to do with the response and its body
+                throw new ResponseParsingException($response, $content, '', 0);
+            } else {
+                if ($response->getStatusCode() == 500) {
+                    throw new UnexpectedValueException(
+                        'An OAuth server error was encountered that did not contain a JSON body',
+                        0,
+                        $e
+                    );
+                }
+
+                return $content;
             }
-
-            return $content;
         }
     }
 
@@ -774,6 +798,8 @@ public function getResourceOwner(AccessToken $token)
      *
      * @param  AccessToken $token
      * @return mixed
+     * @throws ResponseParsingException if the flag $mayThrowResponseParsingException is true and
+     *                                  response body cannot be parsed.
      */
     protected function fetchResourceOwnerDetails(AccessToken $token)
     {

src/Provider/Exception/ResponseParsingException.php

@@ -0,0 +1,76 @@
+<?php
+/**
+ * This file is part of the league/oauth2-client library
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ * @copyright Copyright (c) Alex Bilbie <hello@alexbilbie.com>
+ * @license http://opensource.org/licenses/MIT MIT
+ * @link http://thephpleague.com/oauth2-client/ Documentation
+ * @link https://packagist.org/packages/league/oauth2-client Packagist
+ * @link https://github.com/thephpleague/oauth2-client GitHub
+ */
+
+namespace League\OAuth2\Client\Provider\Exception;
+
+use Exception;
+use Psr\Http\Message\ResponseInterface;
+
+/**
+ * Exception thrown if the parser cannot parse the provider response.
+ */
+class ResponseParsingException extends Exception
+{
+    /**
+     * @var ResponseInterface
+     */
+    protected $response;
+
+    /**
+     * @var string
+     */
+    protected $responseBody;
+
+    /**
+     * @param ResponseInterface $response The response
+     * @param string $responseBody The response body
+     * @param null $message
+     * @param int $code
+     */
+    public function __construct(
+        ResponseInterface $response,
+        $responseBody,
+        $message = null,
+        $code = 0
+    ) {
+        $this->response = $response;
+        $this->responseBody = $responseBody;
+
+        if (null === $message) {
+            $message = sprintf('Cannot parse response body: "%s"', $responseBody);
+        }
+
+        parent::__construct($message, $code);
+    }
+
+    /**
+     * Returns the exception's response.
+     *
+     * @return ResponseInterface
+     */
+    public function getResponse()
+    {
+        return $this->response;
+    }
+
+    /**
+     * Returns the exception's response body.
+     *
+     * @return string
+     */
+    public function getResponseBody()
+    {
+        return $this->responseBody;
+    }
+}

test/src/Provider/AbstractProviderTest.php

@@ -2,6 +2,7 @@
 
 namespace League\OAuth2\Client\Test\Provider;
 
+use League\OAuth2\Client\Provider\Exception\ResponseParsingException;
 use League\OAuth2\Client\OptionProvider\PostAuthOptionProvider;
 use Mockery;
 use ReflectionClass;
@@ -616,7 +617,7 @@ public function parseResponseProvider()
     /**
      * @dataProvider parseResponseProvider
      */
-    public function testParseResponse($body, $type, $parsed, $statusCode = 200)
+    public function testParseResponse($body, $type, $parsed, $statusCode = 200, $provider = null)
     {
         $stream = Mockery::mock(StreamInterface::class, [
             '__toString' => $body,
@@ -632,7 +633,12 @@ public function testParseResponse($body, $type, $parsed, $statusCode = 200)
             ->andReturn($type);
 
         $method = $this->getMethod(AbstractProvider::class, 'parseResponse');
-        $result = $method->invoke($this->getMockProvider(), $response);
+
+        if (null === $provider) {
+            $provider = $this->getMockProvider();
+        }
+
+        $result = $method->invoke($provider, $response);
 
         $this->assertEquals($parsed, $result);
     }
@@ -649,6 +655,33 @@ public function testParseResponseNonJsonFailure()
         $this->testParseResponse('<xml></xml>', 'application/xml', null, 500);
     }
 
+    public function responseParsingExceptionProvider()
+    {
+        return [
+            ['application/json'],
+            ['']
+        ];
+    }
+
+    /**
+     * @dataProvider responseParsingExceptionProvider
+     */
+    public function testResponseParsingException($type)
+    {
+        $provider = $this->getMockProvider();
+        $provider->allowResponseParsingException();
+        $exception = null;
+        try {
+            $this->testParseResponse('{13}', $type, null, 401, $provider);
+        } catch (ResponseParsingException $exception) {
+        }
+        $this->assertInstanceOf(ResponseParsingException::class, $exception);
+        $response = $exception->getResponse();
+        $this->assertSame(401, $response->getStatusCode());
+        $this->assertSame('{13}', $exception->getResponseBody());
+        $provider->disallowResponseParsingException();
+    }
+
     public function getAppendQueryProvider()
     {
         return [

test/src/Provider/Exception/ResponseParsingExceptionTest.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace League\OAuth2\Client\Test\Provider\Exception;
+
+use GuzzleHttp\Psr7\Response;
+use League\OAuth2\Client\Provider\Exception\ResponseParsingException;
+use PHPUnit\Framework\TestCase;
+use Psr\Http\Message\ResponseInterface;
+
+class ResponseParsingExceptionTest extends TestCase
+{
+    private $body = 'foo';
+
+    protected function generateResponseParsingException()
+    {
+        return new ResponseParsingException(new Response('401'), $this->body);
+    }
+
+    public function testGetResponse()
+    {
+        $this->assertInstanceOf(
+            ResponseInterface::class,
+            $this->generateResponseParsingException()->getResponse()
+        );
+    }
+
+    public function testGetResponseBody()
+    {
+        $this->assertSame(
+            $this->body,
+            $this->generateResponseParsingException()->getResponseBody()
+        );
+    }
+
+    public function testMissingMessage()
+    {
+        $this->assertNotEmpty($this->generateResponseParsingException()->getMessage());
+    }
+}

test/src/Provider/Fake.php

@@ -59,6 +59,16 @@ public function getAccessTokenMethod()
         return $this->accessTokenMethod;
     }
 
+    public function allowResponseParsingException()
+    {
+        $this->mayThrowResponseParsingException = true;
+    }
+
+    public function disallowResponseParsingException()
+    {
+        $this->mayThrowResponseParsingException = false;
+    }
+
     protected function createResourceOwner(array $response, AccessToken $token)
     {
         return new Fake\User($response);