Better error handling through wrapping exceptions with richer requests.

config/events.php

@@ -65,6 +65,8 @@ return function (App\EventDispatcher $dispatcher) {
             call_user_func(include(__DIR__ . '/routes.dev.php'), $app);
         }
 
+        $app->add(Middleware\WrapExceptionsWithRequestData::class);
+
         $app->add(Middleware\EnforceSecurity::class);
         $app->add(Middleware\InjectAcl::class);
         $app->add(Middleware\GetCurrentUser::class);
@@ -84,12 +86,12 @@ return function (App\EventDispatcher $dispatcher) {
         $app->add(new Middleware\RemoveSlashes);
         $app->add(new Middleware\ApplyXForwardedProto);
 
-        // Error handling, which should always be near the "last" element.
-        $errorMiddleware = $app->addErrorMiddleware(!$settings->isProduction(), true, true);
-        $errorMiddleware->setDefaultErrorHandler(Slim\Interfaces\ErrorHandlerInterface::class);
-
         // Use PSR-7 compatible sessions.
         $app->add(Middleware\InjectSession::class);
+
+        // Add an error handler for most in-controller/task situations.
+        $errorMiddleware = $app->addErrorMiddleware(!$settings->isProduction(), true, true);
+        $errorMiddleware->setDefaultErrorHandler(Slim\Interfaces\ErrorHandlerInterface::class);
     });
 
     // Build default menus

src/Exception/WrappedException.php

@@ -0,0 +1,16 @@
+<?php
+namespace App\Exception;
+
+use Psr\Http\Message\ServerRequestInterface;
+use Slim\Exception\HttpException;
+use Throwable;
+
+class WrappedException extends HttpException
+{
+    public function __construct(
+        ServerRequestInterface $request,
+        ?Throwable $previous
+    ) {
+        parent::__construct($request, 'Wrapped HTTP Exception', 500, $previous);
+    }
+}

src/Http/ErrorHandler.php

@@ -55,6 +55,10 @@ class ErrorHandler extends \Slim\Handlers\ErrorHandler
         bool $logErrors,
         bool $logErrorDetails
     ): ResponseInterface {
+        if ($exception instanceof Exception\WrappedException) {
+            $exception = $exception->getPrevious();
+        }
+
         if ($exception instanceof Exception) {
             $this->loggerLevel = $exception->getLoggerLevel();
         } elseif ($exception instanceof HttpException) {
@@ -143,15 +147,19 @@ class ErrorHandler extends \Slim\Handlers\ErrorHandler
                 ));
             }
 
-            $view = $this->viewFactory->create($this->request);
+            try {
+                $view = $this->viewFactory->create($this->request);
 
-            return $view->renderToResponse(
-                $response,
-                'system/error_http',
-                [
-                    'exception' => $this->exception,
-                ]
-            );
+                return $view->renderToResponse(
+                    $response,
+                    'system/error_http',
+                    [
+                        'exception' => $this->exception,
+                    ]
+                );
+            } catch (\Throwable $e) {
+                return parent::respond();
+            }
         }
 
         if ($this->exception instanceof NotLoggedInException) {
@@ -240,15 +248,19 @@ class ErrorHandler extends \Slim\Handlers\ErrorHandler
             return $response->write($run->handleException($this->exception));
         }
 
-        $view = $this->viewFactory->create($this->request);
+        try {
+            $view = $this->viewFactory->create($this->request);
 
-        return $view->renderToResponse(
-            $response,
-            'system/error_general',
-            [
-                'exception' => $this->exception,
-            ]
-        );
+            return $view->renderToResponse(
+                $response,
+                'system/error_general',
+                [
+                    'exception' => $this->exception,
+                ]
+            );
+        } catch (\Throwable $e) {
+            return parent::respond();
+        }
     }
 
     protected function withJson(ResponseInterface $response, $data): ResponseInterface

src/Middleware/WrapExceptionsWithRequestData.php

@@ -0,0 +1,29 @@
+<?php
+namespace App\Middleware;
+
+use App\Exception\WrappedException;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\MiddlewareInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+
+/**
+ * Wrap all exceptions thrown past this point with rich metadata.
+ */
+class WrapExceptionsWithRequestData implements MiddlewareInterface
+{
+    /**
+     * @param ServerRequestInterface $request
+     * @param RequestHandlerInterface $handler
+     *
+     * @return ResponseInterface
+     */
+    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
+    {
+        try {
+            return $handler->handle($request);
+        } catch (\Throwable $e) {
+            throw new WrappedException($request, $e);
+        }
+    }
+}