Add support for PSR-3

Slim/App.php

@@ -16,6 +16,7 @@
 use Psr\Http\Message\ServerRequestInterface;
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
+use Psr\Log\LoggerInterface;
 use Slim\Factory\ServerRequestCreatorFactory;
 use Slim\Interfaces\CallableResolverInterface;
 use Slim\Interfaces\MiddlewareDispatcherInterface;
@@ -140,23 +141,26 @@ public function addRoutingMiddleware(): RoutingMiddleware
     /**
      * Add the Slim built-in error middleware to the app middleware stack
      *
-     * @param bool $displayErrorDetails
-     * @param bool $logErrors
-     * @param bool $logErrorDetails
+     * @param bool                 $displayErrorDetails
+     * @param bool                 $logErrors
+     * @param bool                 $logErrorDetails
+     * @param LoggerInterface|null $logger
      *
      * @return ErrorMiddleware
      */
     public function addErrorMiddleware(
         bool $displayErrorDetails,
         bool $logErrors,
-        bool $logErrorDetails
+        bool $logErrorDetails,
+        ?LoggerInterface $logger = null
     ): ErrorMiddleware {
         $errorMiddleware = new ErrorMiddleware(
             $this->getCallableResolver(),
             $this->getResponseFactory(),
             $displayErrorDetails,
             $logErrors,
-            $logErrorDetails
+            $logErrorDetails,
+            $logger
         );
         $this->add($errorMiddleware);
         return $errorMiddleware;

Slim/Handlers/ErrorHandler.php

@@ -13,6 +13,7 @@
 use Psr\Http\Message\ResponseFactoryInterface;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\ServerRequestInterface;
+use Psr\Log\LoggerInterface;
 use RuntimeException;
 use Slim\Error\Renderers\HtmlErrorRenderer;
 use Slim\Error\Renderers\JsonErrorRenderer;
@@ -23,6 +24,7 @@
 use Slim\Interfaces\CallableResolverInterface;
 use Slim\Interfaces\ErrorHandlerInterface;
 use Slim\Interfaces\ErrorRendererInterface;
+use Slim\Logger;
 use Throwable;
 
 use function array_intersect;
@@ -121,14 +123,24 @@ class ErrorHandler implements ErrorHandlerInterface
      */
     protected $responseFactory;
 
+    /*
+     * @var LoggerInterface
+     */
+    protected $logger;
+
     /**
      * @param CallableResolverInterface $callableResolver
      * @param ResponseFactoryInterface  $responseFactory
+     * @param LoggerInterface|null      $logger
      */
-    public function __construct(CallableResolverInterface $callableResolver, ResponseFactoryInterface $responseFactory)
-    {
+    public function __construct(
+        CallableResolverInterface $callableResolver,
+        ResponseFactoryInterface $responseFactory,
+        ?LoggerInterface $logger = null
+    ) {
         $this->callableResolver = $callableResolver;
         $this->responseFactory = $responseFactory;
+        $this->logger = $logger ?: $this->getDefaultLogger();
     }
 
     /**
@@ -311,7 +323,17 @@ protected function writeToErrorLog(): void
      */
     protected function logError(string $error): void
     {
-        error_log($error);
+        $this->logger->error($error);
+    }
+
+    /**
+     * Returns a default logger implementation.
+     *
+     * @return LoggerInterface
+     */
+    protected function getDefaultLogger(): LoggerInterface
+    {
+        return new Logger();
     }
 
     /**

Slim/Logger.php

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @license https://github.com/slimphp/Slim/blob/4.x/LICENSE.md (MIT License)
+ */
+
+declare(strict_types=1);
+
+namespace Slim;
+
+use Psr\Log\AbstractLogger;
+use Psr\Log\InvalidArgumentException;
+
+class Logger extends AbstractLogger
+{
+    /**
+     * @param mixed  $level
+     * @param string $message
+     * @param array  $context
+     *
+     * @return void
+     *
+     * @throws InvalidArgumentException
+     */
+    public function log($level, $message, array $context = [])
+    {
+        error_log($message);
+    }
+}

Slim/Middleware/ErrorMiddleware.php

@@ -15,6 +15,7 @@
 use Psr\Http\Message\ServerRequestInterface;
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
+use Psr\Log\LoggerInterface;
 use Slim\Exception\HttpException;
 use Slim\Handlers\ErrorHandler;
 use Slim\Interfaces\CallableResolverInterface;
@@ -51,6 +52,11 @@ class ErrorMiddleware implements MiddlewareInterface
      */
     protected $logErrorDetails;
 
+    /**
+     * @var LoggerInterface|null
+     */
+    protected $logger;
+
     /**
      * @var ErrorHandlerInterface[]|callable[]
      */
@@ -72,19 +78,22 @@ class ErrorMiddleware implements MiddlewareInterface
      * @param bool                      $displayErrorDetails
      * @param bool                      $logErrors
      * @param bool                      $logErrorDetails
+     * @param LoggerInterface|null      $logger
      */
     public function __construct(
         CallableResolverInterface $callableResolver,
         ResponseFactoryInterface $responseFactory,
         bool $displayErrorDetails,
         bool $logErrors,
-        bool $logErrorDetails
+        bool $logErrorDetails,
+        ?LoggerInterface $logger = null
     ) {
         $this->callableResolver = $callableResolver;
         $this->responseFactory = $responseFactory;
         $this->displayErrorDetails = $displayErrorDetails;
         $this->logErrors = $logErrors;
         $this->logErrorDetails = $logErrorDetails;
+        $this->logger = $logger;
     }
 
     /**
@@ -150,7 +159,11 @@ public function getErrorHandler(string $type)
     public function getDefaultErrorHandler()
     {
         if ($this->defaultErrorHandler === null) {
-            $this->defaultErrorHandler = new ErrorHandler($this->callableResolver, $this->responseFactory);
+            $this->defaultErrorHandler = new ErrorHandler(
+                $this->callableResolver,
+                $this->responseFactory,
+                $this->logger
+            );
         }
 
         return $this->callableResolver->resolve($this->defaultErrorHandler);

composer.json

@@ -40,7 +40,8 @@
         "psr/http-factory": "^1.0",
         "psr/http-message": "^1.0",
         "psr/http-server-handler": "^1.0",
-        "psr/http-server-middleware": "^1.0"
+        "psr/http-server-middleware": "^1.0",
+        "psr/log": "^1.1"
     },
     "require-dev": {
         "ext-simplexml": "*",

tests/AppTest.php

@@ -19,6 +19,7 @@
 use Psr\Http\Message\UriInterface;
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
+use Psr\Log\LoggerInterface;
 use ReflectionClass;
 use ReflectionProperty;
 use RuntimeException;
@@ -724,11 +725,14 @@ public function testAddErrorMiddleware()
         /** @var ResponseFactoryInterface $responseFactory */
         $responseFactory = $this->prophesize(ResponseFactoryInterface::class)->reveal();
 
+        /** @var LoggerInterface $logger */
+        $logger = $this->prophesize(LoggerInterface::class)->reveal();
+
         // Create the app.
         $app = new App($responseFactory);
 
         // Add the error middleware.
-        $errorMiddleware = $app->addErrorMiddleware(true, true, true);
+        $errorMiddleware = $app->addErrorMiddleware(true, true, true, $logger);
 
         // Check that the error middleware really has been added to the tip of the app middleware stack.
         $middlewareDispatcherProperty = new ReflectionProperty(App::class, 'middlewareDispatcher');

tests/Handlers/ErrorHandlerTest.php

@@ -11,6 +11,7 @@
 namespace Slim\Tests\Handlers;
 
 use Psr\Http\Message\ResponseInterface;
+use Psr\Log\LoggerInterface;
 use ReflectionClass;
 use ReflectionMethod;
 use ReflectionProperty;
@@ -28,6 +29,11 @@
 
 class ErrorHandlerTest extends TestCase
 {
+    private function getMockLogger(): LoggerInterface
+    {
+        return $this->createMock(LoggerInterface::class);
+    }
+
     public function testDetermineRenderer()
     {
         $handler = $this
@@ -303,16 +309,16 @@ public function testWriteToErrorLog()
             ->createServerRequest('/', 'GET')
             ->withHeader('Accept', 'application/json');
 
-        $handler = $this->getMockBuilder(ErrorHandler::class)
-            ->setConstructorArgs([
-                'callableResolver' => $this->getCallableResolver(),
-                'responseFactory' => $this->getResponseFactory(),
-            ])
-            ->setMethods(['logError'])
-            ->getMock();
+        $logger = $this->getMockLogger();
 
-        $handler->expects(self::once())
-            ->method('logError')
+        $handler = new ErrorHandler(
+            $this->getCallableResolver(),
+            $this->getResponseFactory(),
+            $logger
+        );
+
+        $logger->expects(self::once())
+            ->method('error')
             ->willReturnCallback(static function (string $error) {
                 self::assertStringNotContainsString(
                     'set "displayErrorDetails" to true in the ErrorHandler constructor',
@@ -330,16 +336,16 @@ public function testWriteToErrorLogShowTip()
             ->createServerRequest('/', 'GET')
             ->withHeader('Accept', 'application/json');
 
-        $handler = $this->getMockBuilder(ErrorHandler::class)
-            ->setConstructorArgs([
-                'callableResolver' => $this->getCallableResolver(),
-                'responseFactory' => $this->getResponseFactory(),
-            ])
-            ->setMethods(['logError'])
-            ->getMock();
+        $logger = $this->getMockLogger();
+
+        $handler = new ErrorHandler(
+            $this->getCallableResolver(),
+            $this->getResponseFactory(),
+            $logger
+        );
 
-        $handler->expects(self::once())
-            ->method('logError')
+        $logger->expects(self::once())
+            ->method('error')
             ->willReturnCallback(static function (string $error) {
                 self::assertStringContainsString(
                     'set "displayErrorDetails" to true in the ErrorHandler constructor',