Move error handling to dedicated controller instead of middleware

application/container/ContainerBuilder.php

@@ -9,6 +9,7 @@ use Shaarli\Bookmark\BookmarkServiceInterface;
 use Shaarli\Config\ConfigManager;
 use Shaarli\Feed\FeedBuilder;
 use Shaarli\Formatter\FormatterFactory;
+use Shaarli\Front\Controller\Visitor\ErrorController;
 use Shaarli\History;
 use Shaarli\Http\HttpAccess;
 use Shaarli\Netscape\NetscapeBookmarkUtils;
@@ -148,6 +149,10 @@ class ContainerBuilder
             );
         };
 
+        $container['errorHandler'] = function (ShaarliContainer $container): ErrorController {
+            return new ErrorController($container);
+        };
+
         return $container;
     }
 }

application/front/ShaarliMiddleware.php

@@ -3,7 +3,6 @@
 namespace Shaarli\Front;
 
 use Shaarli\Container\ShaarliContainer;
-use Shaarli\Front\Exception\ShaarliFrontException;
 use Shaarli\Front\Exception\UnauthorizedException;
 use Slim\Http\Request;
 use Slim\Http\Response;
@@ -53,35 +52,12 @@ class ShaarliMiddleware
             $this->checkOpenShaarli($request, $response, $next);
 
             return $next($request, $response);
-        } catch (ShaarliFrontException $e) {
-            // Possible functional error
-            $this->container->pageBuilder->reset();
-            $this->container->pageBuilder->assign('message', nl2br($e->getMessage()));
-
-            $response = $response->withStatus($e->getCode());
-
-            return $response->write($this->container->pageBuilder->render('error', $this->container->basePath));
         } catch (UnauthorizedException $e) {
             $returnUrl = urlencode($this->container->environment['REQUEST_URI']);
 
             return $response->withRedirect($this->container->basePath . '/login?returnurl=' . $returnUrl);
-        } catch (\Throwable $e) {
-            // Unknown error encountered
-            $this->container->pageBuilder->reset();
-            if ($this->container->conf->get('dev.debug', false)) {
-                $this->container->pageBuilder->assign('message', $e->getMessage());
-                $this->container->pageBuilder->assign(
-                    'stacktrace',
-                    nl2br(get_class($e) .': '. PHP_EOL . $e->getTraceAsString())
-                );
-            } else {
-                $this->container->pageBuilder->assign('message', t('An unexpected error occurred.'));
-            }
-
-            $response = $response->withStatus(500);
-
-            return $response->write($this->container->pageBuilder->render('error', $this->container->basePath));
         }
+        // Other exceptions are handled by ErrorController
     }
 
     /**

application/front/controller/visitor/ErrorController.php

@@ -0,0 +1,45 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Shaarli\Front\Controller\Visitor;
+
+use Shaarli\Front\Exception\ShaarliFrontException;
+use Slim\Http\Request;
+use Slim\Http\Response;
+
+/**
+ * Controller used to render the error page, with a provided exception.
+ * It is actually used as a Slim error handler.
+ */
+class ErrorController extends ShaarliVisitorController
+{
+    public function __invoke(Request $request, Response $response, \Throwable $throwable): Response
+    {
+        // Unknown error encountered
+        $this->container->pageBuilder->reset();
+
+        if ($throwable instanceof ShaarliFrontException) {
+            // Functional error
+            $this->assignView('message', nl2br($throwable->getMessage()));
+
+            $response = $response->withStatus($throwable->getCode());
+        } else {
+            // Internal error (any other Throwable)
+            if ($this->container->conf->get('dev.debug', false)) {
+                $this->assignView('message', $throwable->getMessage());
+                $this->assignView(
+                    'stacktrace',
+                    nl2br(get_class($throwable) .': '. PHP_EOL . $throwable->getTraceAsString())
+                );
+            } else {
+                $this->assignView('message', t('An unexpected error occurred.'));
+            }
+
+            $response = $response->withStatus(500);
+        }
+
+
+        return $response->write($this->render('error'));
+    }
+}

tests/front/ShaarliMiddlewareTest.php

@@ -74,7 +74,8 @@ class ShaarliMiddlewareTest extends TestCase
     }
 
     /**
-     * Test middleware execution with controller throwing a known front exception
+     * Test middleware execution with controller throwing a known front exception.
+     * The exception should be thrown to be later handled by the error handler.
      */
     public function testMiddlewareExecutionWithFrontException(): void
     {
@@ -99,16 +100,14 @@ class ShaarliMiddlewareTest extends TestCase
         });
         $this->container->pageBuilder = $pageBuilder;
 
-        /** @var Response $result */
-        $result = $this->middleware->__invoke($request, $response, $controller);
+        $this->expectException(LoginBannedException::class);
 
-        static::assertInstanceOf(Response::class, $result);
-        static::assertSame(401, $result->getStatusCode());
-        static::assertContains('error', (string) $result->getBody());
+        $this->middleware->__invoke($request, $response, $controller);
     }
 
     /**
      * Test middleware execution with controller throwing a not authorized exception
+     * The middle should send a redirection response to the login page.
      */
     public function testMiddlewareExecutionWithUnauthorizedException(): void
     {
@@ -136,9 +135,10 @@ class ShaarliMiddlewareTest extends TestCase
     }
 
     /**
-     * Test middleware execution with controller throwing a not authorized exception
+     * Test middleware execution with controller throwing a not authorized exception.
+     * The exception should be thrown to be later handled by the error handler.
      */
-    public function testMiddlewareExecutionWithServerExceptionWith(): void
+    public function testMiddlewareExecutionWithServerException(): void
     {
         $request = $this->createMock(Request::class);
         $request->method('getUri')->willReturnCallback(function (): Uri {
@@ -148,9 +148,11 @@ class ShaarliMiddlewareTest extends TestCase
             return $uri;
         });
 
+        $dummyException = new class() extends \Exception {};
+
         $response = new Response();
-        $controller = function (): void {
-            throw new \Exception();
+        $controller = function () use ($dummyException): void {
+            throw $dummyException;
         };
 
         $parameters = [];
@@ -165,12 +167,9 @@ class ShaarliMiddlewareTest extends TestCase
             })
         ;
 
-        /** @var Response $result */
-        $result = $this->middleware->__invoke($request, $response, $controller);
+        $this->expectException(get_class($dummyException));
 
-        static::assertSame(500, $result->getStatusCode());
-        static::assertContains('error', (string) $result->getBody());
-        static::assertSame('An unexpected error occurred.', $parameters['message']);
+        $this->middleware->__invoke($request, $response, $controller);
     }
 
     public function testMiddlewareExecutionWithUpdates(): void

tests/front/controller/visitor/ErrorControllerTest.php

@@ -0,0 +1,70 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Shaarli\Front\Controller\Visitor;
+
+use PHPUnit\Framework\TestCase;
+use Shaarli\Front\Exception\ShaarliFrontException;
+use Slim\Http\Request;
+use Slim\Http\Response;
+
+class ErrorControllerTest extends TestCase
+{
+    use FrontControllerMockHelper;
+
+    /** @var ErrorController */
+    protected $controller;
+
+    public function setUp(): void
+    {
+        $this->createContainer();
+
+        $this->controller = new ErrorController($this->container);
+    }
+
+    /**
+     * Test displaying error with a ShaarliFrontException: display exception message and use its code for HTTTP code
+     */
+    public function testDisplayFrontExceptionError(): void
+    {
+        $request = $this->createMock(Request::class);
+        $response = new Response();
+
+        $message = 'error message';
+        $errorCode = 418;
+
+        // Save RainTPL assigned variables
+        $assignedVariables = [];
+        $this->assignTemplateVars($assignedVariables);
+
+        $result = ($this->controller)(
+            $request,
+            $response,
+            new class($message, $errorCode) extends ShaarliFrontException {}
+        );
+
+        static::assertSame($errorCode, $result->getStatusCode());
+        static::assertSame($message, $assignedVariables['message']);
+        static::assertArrayNotHasKey('stacktrace', $assignedVariables);
+    }
+
+    /**
+     * Test displaying error with any exception (no debug): only display an error occurred with HTTP 500.
+     */
+    public function testDisplayAnyExceptionErrorNoDebug(): void
+    {
+        $request = $this->createMock(Request::class);
+        $response = new Response();
+
+        // Save RainTPL assigned variables
+        $assignedVariables = [];
+        $this->assignTemplateVars($assignedVariables);
+
+        $result = ($this->controller)($request, $response, new \Exception('abc'));
+
+        static::assertSame(500, $result->getStatusCode());
+        static::assertSame('An unexpected error occurred.', $assignedVariables['message']);
+        static::assertArrayNotHasKey('stacktrace', $assignedVariables);
+    }
+}