Introspective handling

src/Router/Exceptions/NotFound404Exception.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Gacela\Router\Exceptions;
+
+use RuntimeException;
+
+final class NotFound404Exception extends RuntimeException
+{
+    public function __construct()
+    {
+        parent::__construct('Error 404 - Not Found');
+    }
+}

src/Router/Handlers.php

@@ -4,13 +4,22 @@
 
 namespace Gacela\Router;
 
+use Exception;
+use Gacela\Router\Exceptions\NotFound404Exception;
+use Gacela\Router\Handlers\FallbackExceptionHandler;
+use Gacela\Router\Handlers\NotFound404ExceptionHandler;
+
 final class Handlers
 {
     /** @var array<class-string, callable> */
     private array $handlers = [];
 
+    public function __construct()
+    {
+        $this->addBuiltInHandlers();
+    }
     /**
-     * @param class-string $exception
+     * @param class-string<Exception> $exception
      */
     public function handle(string $exception, callable $handler): self
     {
@@ -25,4 +34,16 @@ public function getAllHandlers(): array
     {
         return $this->handlers;
     }
+
+    private function addBuiltInHandlers(): void
+    {
+        $this->handle(
+            NotFound404Exception::class,
+            static fn (NotFound404Exception $exception) => (new NotFound404ExceptionHandler())->__invoke($exception),
+        );
+        $this->handle(
+            Exception::class,
+            static fn (Exception $exception) => (new FallbackExceptionHandler())->__invoke($exception),
+        );
+    }
 }

src/Router/Handlers/FallbackExceptionHandler.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Gacela\Router\Handlers;
+
+use Exception;
+
+final class FallbackExceptionHandler
+{
+    public function __invoke(Exception $exception): string
+    {
+        header('HTTP/1.1 500 Internal Server Error');
+
+        return '';
+    }
+}

src/Router/Handlers/NotFound404ExceptionHandler.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Gacela\Router\Handlers;
+
+use Gacela\Router\Exceptions\NotFound404Exception;
+
+final class NotFound404ExceptionHandler
+{
+    public function __invoke(NotFound404Exception $notFound404Exception): string
+    {
+        header('HTTP/1.0 404 Not Found');
+
+        return '';
+    }
+}

src/Router/Router.php

@@ -6,8 +6,8 @@
 
 use Closure;
 use Exception;
-use Gacela\Router\Controllers\NotFound404Controller;
 use Gacela\Router\Entities\Route;
+use Gacela\Router\Exceptions\NotFound404Exception;
 use ReflectionException;
 use ReflectionFunction;
 
@@ -34,9 +34,10 @@ public static function configure(Closure $fn): void
         $fn(...$params);
 
         try {
-            echo self::findRoute($routes)->run($bindings);
+            echo self::findRoute($routes)
+                ->run($bindings);
         } catch (Exception $exception) {
-            echo self::handleException($handlers, $exception);
+            echo (string) self::findHandler($handlers, $exception)($exception);
         }
     }
 
@@ -48,18 +49,17 @@ private static function findRoute(Routes $routes): Route
             }
         }
 
-        return new Route('', '/', NotFound404Controller::class);
+        throw new NotFound404Exception();
     }
 
-    private static function handleException(Handlers $handlers, Exception $exception): string
+    private static function findHandler(Handlers $handlers, Exception $exception): callable
     {
         $handler = $handlers->getAllHandlers()[get_class($exception)] ?? null;
 
         if ($handler === null) {
-            header('HTTP/1.1 500 Internal Server Error');
-            return '';
+            return $handlers->getAllHandlers()[Exception::class];
         }
 
-        return $handler($exception);
+        return $handler;
     }
 }

tests/Feature/Router/ErrorHandlingTest.php

@@ -4,7 +4,9 @@
 
 namespace GacelaTest\Feature\Router;
 
+use Exception;
 use Gacela\Router\Entities\Request;
+use Gacela\Router\Exceptions\NotFound404Exception;
 use Gacela\Router\Handlers;
 use Gacela\Router\Router;
 use Gacela\Router\Routes;
@@ -101,7 +103,7 @@ public function test_respond_500_status_when_unhandled_exception(): void
         ], $this->headers());
     }
 
-    public function test_handle_handled_exception(): void
+    public function test_handle_handled_exception_with_anonymous_function(): void
     {
         $_SERVER['REQUEST_URI'] = 'https://example.org/expected/uri';
         $_SERVER['REQUEST_METHOD'] = Request::METHOD_GET;
@@ -116,7 +118,52 @@ public function test_handle_handled_exception(): void
         });
 
         $this->expectOutputString('Handled!');
+        self::assertSame([
+            [
+                'header' => 'HTTP/1.1 418 I\'m a teapot',
+                'replace' => true,
+                'response_code' => 0,
+            ],
+        ], $this->headers());
+    }
+
+    public function test_custom_404_handler(): void
+    {
+        $_SERVER['REQUEST_URI'] = 'https://example.org/expected/uri';
+        $_SERVER['REQUEST_METHOD'] = Request::METHOD_GET;
+
+        Router::configure(static function (Handlers $handlers): void {
+            $handlers->handle(NotFound404Exception::class, static function (): string {
+                \Gacela\Router\header('HTTP/1.1 418 I\'m a teapot');
+                return 'Handled!';
+            });
+        });
 
+        $this->expectOutputString('Handled!');
+        self::assertSame([
+            [
+                'header' => 'HTTP/1.1 418 I\'m a teapot',
+                'replace' => true,
+                'response_code' => 0,
+            ],
+        ], $this->headers());
+    }
+
+    public function test_custom_fallback_handler(): void
+    {
+        $_SERVER['REQUEST_URI'] = 'https://example.org/expected/uri';
+        $_SERVER['REQUEST_METHOD'] = Request::METHOD_GET;
+
+        Router::configure(static function (Handlers $handlers, Routes $routes): void {
+            $routes->get('expected/uri', FakeControllerWithUnhandledException::class);
+
+            $handlers->handle(Exception::class, static function (): string {
+                \Gacela\Router\header('HTTP/1.1 418 I\'m a teapot');
+                return 'Handled!';
+            });
+        });
+
+        $this->expectOutputString('Handled!');
         self::assertSame([
             [
                 'header' => 'HTTP/1.1 418 I\'m a teapot',

tests/Feature/header.php

@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Gacela\Router\Controllers {
+namespace Gacela\Router {
     function header(string $header, bool $replace = true, int $responseCode = 0): void
     {
         /** @var list<array{header: string, replace: boolean, response_code: int}> | null $testHeaders */
@@ -22,7 +22,27 @@ function header(string $header, bool $replace = true, int $responseCode = 0): vo
 
 // TODO: Find a better way to mock the head function in different namespaces
 
-namespace Gacela\Router {
+namespace Gacela\Router\Handlers {
+    function header(string $header, bool $replace = true, int $responseCode = 0): void
+    {
+        /** @var list<array{header: string, replace: boolean, response_code: int}> | null $testHeaders */
+        global $testHeaders;
+
+        if (!\is_array($testHeaders)) {
+            $testHeaders = [];
+        }
+
+        $testHeaders[] = [
+            'header' => $header,
+            'replace' => $replace,
+            'response_code' => $responseCode,
+        ];
+    }
+}
+
+// TODO: Find a better way to mock the head function in different namespaces
+
+namespace Gacela\Router\Controllers {
     function header(string $header, bool $replace = true, int $responseCode = 0): void
     {
         /** @var list<array{header: string, replace: boolean, response_code: int}> | null $testHeaders */