Add transformers system

Author: veewee

.travis.yml

@@ -1,13 +1,12 @@
 language: php
 
-php:
-  - 7.2
-  - nightly
-
 env:
-  matrix:
-    -
-    - DEPENDENCIES=--prefer-lowest
+    global:
+        - DEFAULT_COMPOSER_FLAGS="--optimize-autoloader --no-interaction --no-progress"
+        - COMPOSER_FLAGS=""
+
+before_install:
+    - alias composer=composer\ --no-interaction && composer selfupdate
 
 cache:
   directories:
@@ -18,11 +17,28 @@ matrix:
   allow_failures:
     - php: nightly
 
-before_install:
-  - alias composer=composer\ --no-interaction && composer selfupdate
-
-install:
-  - travis_retry composer update --no-progress --profile --no-scripts --no-suggest $DEPENDENCIES
+jobs:
+    include:
+        - &STANDARD_TEST_JOB
+            stage: Test
+            php: 7.2
+            install:
+                - travis_retry composer update $DEFAULT_COMPOSER_FLAGS $COMPOSER_FLAGS
+                - composer info -D | sort
+            script:
+                - vendor/bin/grumphp run
+        -
+            <<: *STANDARD_TEST_JOB
+            stage: Test
+            php: 7.2
+            env: COMPOSER_FLAGS="--prefer-stable --prefer-lowest"
+        -
+            <<: *STANDARD_TEST_JOB
+            stage: Test
+            php: nightly
+            env: COMPOSER_FLAGS="--ignore-platform-reqs" PHP_CS_FIXER_IGNORE_ENV=1 PHP_CS_FIXER_FUTURE_MODE=1
+            script:
+                - vendor/bin/grumphp run
 
-script:
-   - vendor/bin/grumphp run
+    allow_failures:
+        - php: nightly

README.md

@@ -67,6 +67,36 @@ Body:
 }
 ```
 
+## Adding custom exception transformations
+
+Currently, we automatically transform exceptions from following packages to an ApiProblem instance:
+
+- phpro/api-problem
+- symfony/http-kernel
+- symfony/security
+
+Besides that, all other errors are transformed to a basic `ExceptionApiProblem` instance.
+
+If you want to add custom transformations, you can implement the `ExceptionTransformerInterface`
+ and register it in the symfony container with the `phpro.api_problem.exception_transformer` tag.
+ 
+```php
+use Phpro\ApiProblemBundle\Transformer\ExceptionTransformerInterface;
+
+class MyTransformer implements ExceptionTransformerInterface
+{
+    public function transform(\Throwable $exception): ApiProblemInterface
+    {
+        return new MyApiProblem($exception);
+    }
+
+    public function accepts(\Throwable $exception): bool
+    {
+        return $exception instanceof MyException;
+    }
+}
+```
+
 ## About
 
 ### Submitting bugs and feature requests

composer.json

@@ -2,12 +2,6 @@
     "name": "phpro/api-problem-bundle",
     "description": "RFC7807 Problem details integration for Symfony",
     "type": "library",
-    "require-dev": {
-        "friendsofphp/php-cs-fixer": "^2.12",
-        "matthiasnoback/symfony-dependency-injection-test": "^3.0",
-        "phpro/grumphp": "^0.14.1",
-        "phpunit/phpunit": "^7.2"
-    },
     "license": "MIT",
     "authors": [
         {
@@ -17,11 +11,18 @@
     ],
     "require": {
         "php": "^7.2",
-        "phpro/api-problem": "dev-master@dev",
+        "phpro/api-problem": "^1.0",
         "symfony/dependency-injection": "^4.1",
         "symfony/event-dispatcher": "^4.1",
         "symfony/http-kernel": "^4.1"
     },
+    "require-dev": {
+        "friendsofphp/php-cs-fixer": "^2.12",
+        "matthiasnoback/symfony-dependency-injection-test": "^3.0",
+        "phpro/grumphp": "^0.14.1",
+        "phpunit/phpunit": "^7.2",
+        "symfony/security": "^4.1"
+    },
     "config": {
         "sort-packages": true
     },
@@ -34,11 +35,5 @@
         "psr-4": {
             "PhproTest\\ApiProblemBundle\\": "test/"
         }
-    },
-    "repositories": [
-        {
-            "type": "git",
-            "url": "https://github.com/phpro/api-problem.git"
-        }
-    ]
+    }
 }

config/services.xml

@@ -7,8 +7,21 @@
             id="Phpro\ApiProblemBundle\EventListener\JsonApiProblemExceptionListener"
             class="Phpro\ApiProblemBundle\EventListener\JsonApiProblemExceptionListener"
         >
+            <argument key="$exceptionTransformer" type="service" id="Phpro\ApiProblemBundle\Transformer\Chain" />
             <argument key="$debug" >%kernel.debug%</argument>
             <tag name="kernel.event_listener" event="kernel.exception" method="onKernelException" />
         </service>
+        <service id="Phpro\ApiProblemBundle\Transformer\Chain" class="Phpro\ApiProblemBundle\Transformer\Chain">
+            <argument type="tagged" tag="phpro.api_problem.exception_transformer" />
+        </service>
+        <service id="Phpro\ApiProblemBundle\Transformer\ApiProblemExceptionTransformer" class="Phpro\ApiProblemBundle\Transformer\ApiProblemExceptionTransformer">
+            <tag name="phpro.api_problem.exception_transformer" />
+        </service>
+        <service id="Phpro\ApiProblemBundle\Transformer\HttpExceptionTransformer" class="Phpro\ApiProblemBundle\Transformer\HttpExceptionTransformer">
+            <tag name="phpro.api_problem.exception_transformer" />
+        </service>
+        <service id="Phpro\ApiProblemBundle\Transformer\SecurityExceptionTransformer" class="Phpro\ApiProblemBundle\Transformer\SecurityExceptionTransformer">
+            <tag name="phpro.api_problem.exception_transformer" />
+        </service>
     </services>
 </container>

src/EventListener/JsonApiProblemExceptionListener.php

@@ -6,21 +6,27 @@
 
 use Phpro\ApiProblem\ApiProblemInterface;
 use Phpro\ApiProblem\DebuggableApiProblemInterface;
-use Phpro\ApiProblem\Exception\ApiProblemException;
 use Phpro\ApiProblem\Http\ExceptionApiProblem;
+use Phpro\ApiProblemBundle\Transformer\ExceptionTransformerInterface;
 use Symfony\Component\HttpFoundation\JsonResponse;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
 
 class JsonApiProblemExceptionListener
 {
+    /**
+     * @var ExceptionTransformerInterface
+     */
+    private $exceptionTransformer;
+
     /**
      * @var bool
      */
     private $debug;
 
-    public function __construct(bool $debug)
+    public function __construct(ExceptionTransformerInterface $exceptionTransformer, bool $debug)
     {
+        $this->exceptionTransformer = $exceptionTransformer;
         $this->debug = $debug;
     }
 
@@ -40,11 +46,11 @@ public function onKernelException(GetResponseForExceptionEvent $event): void
 
     private function convertExceptionToProblem(\Throwable $exception): ApiProblemInterface
     {
-        if ($exception instanceof ApiProblemException) {
-            return $exception->getApiProblem();
+        if (!$this->exceptionTransformer->accepts($exception)) {
+            return new ExceptionApiProblem($exception);
         }
 
-        return new ExceptionApiProblem($exception);
+        return $this->exceptionTransformer->transform($exception);
     }
 
     private function generateResponse(ApiProblemInterface $apiProblem): JsonResponse

src/Transformer/ApiProblemExceptionTransformer.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Phpro\ApiProblemBundle\Transformer;
+
+use Phpro\ApiProblem\ApiProblemInterface;
+use Phpro\ApiProblem\Exception\ApiProblemException;
+
+class ApiProblemExceptionTransformer implements ExceptionTransformerInterface
+{
+    /**
+     * @param ApiProblemException $exception
+     */
+    public function transform(\Throwable $exception): ApiProblemInterface
+    {
+        return $exception->getApiProblem();
+    }
+
+    public function accepts(\Throwable $exception): bool
+    {
+        return $exception instanceof ApiProblemException;
+    }
+}

src/Transformer/Chain.php

@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Phpro\ApiProblemBundle\Transformer;
+
+use Phpro\ApiProblem\ApiProblemInterface;
+use Phpro\ApiProblem\Http\ExceptionApiProblem;
+
+class Chain implements ExceptionTransformerInterface
+{
+    /**
+     * @var ExceptionTransformerInterface[]
+     */
+    private $transformers;
+
+    public function __construct(ExceptionTransformerInterface ...$transformers)
+    {
+        $this->transformers = $transformers;
+    }
+
+    public function transform(\Throwable $exception): ApiProblemInterface
+    {
+        foreach ($this->transformers as $transformer) {
+            if ($transformer->accepts($exception)) {
+                return $transformer->transform($exception);
+            }
+        }
+
+        return new ExceptionApiProblem($exception);
+    }
+
+    public function accepts(\Throwable $exception): bool
+    {
+        return true;
+    }
+}

src/Transformer/ExceptionTransformerInterface.php

@@ -0,0 +1,14 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Phpro\ApiProblemBundle\Transformer;
+
+use Phpro\ApiProblem\ApiProblemInterface;
+
+interface ExceptionTransformerInterface
+{
+    public function transform(\Throwable $exception): ApiProblemInterface;
+
+    public function accepts(\Throwable $exception): bool;
+}

src/Transformer/HttpExceptionTransformer.php

@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Phpro\ApiProblemBundle\Transformer;
+
+use Phpro\ApiProblem\ApiProblemInterface;
+use Phpro\ApiProblem\Http\ExceptionApiProblem;
+use Symfony\Component\HttpKernel\Exception\HttpException;
+
+class HttpExceptionTransformer implements ExceptionTransformerInterface
+{
+    /**
+     * @param HttpException $exception
+     */
+    public function transform(\Throwable $exception): ApiProblemInterface
+    {
+        return new ExceptionApiProblem(
+            new HttpException(
+                $exception->getStatusCode(),
+                $exception->getMessage(),
+                $exception,
+                $exception->getHeaders(),
+                $exception->getStatusCode()
+            )
+        );
+    }
+
+    public function accepts(\Throwable $exception): bool
+    {
+        return $exception instanceof HttpException;
+    }
+}

src/Transformer/SecurityExceptionTransformer.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Phpro\ApiProblemBundle\Transformer;
+
+use Phpro\ApiProblem\ApiProblemInterface;
+use Phpro\ApiProblem\Http\ForbiddenProblem;
+use Phpro\ApiProblem\Http\UnauthorizedProblem;
+use Symfony\Component\Security\Core\Exception\AuthenticationException;
+use Symfony\Component\Security\Core\Exception\ExceptionInterface as SecurityException;
+
+class SecurityExceptionTransformer implements ExceptionTransformerInterface
+{
+    public function transform(\Throwable $exception): ApiProblemInterface
+    {
+        if ($exception instanceof AuthenticationException) {
+            return new UnauthorizedProblem($exception->getMessage());
+        }
+
+        return new ForbiddenProblem($exception->getMessage());
+    }
+
+    public function accepts(\Throwable $exception): bool
+    {
+        return $exception instanceof SecurityException;
+    }
+}