slimphp/Slim · error · RuntimeException

An unexpected error occurred while performing routing.

Error message

An unexpected error occurred while performing routing.

What it means

Error "An unexpected error occurred while performing routing." thrown in slimphp/Slim.

Source

Thrown at Slim/Middleware/RoutingMiddleware.php:84

        switch ($routeStatus) {
            case RoutingResults::FOUND:
                $routeArguments = $routingResults->getRouteArguments();
                $routeIdentifier = $routingResults->getRouteIdentifier() ?? '';
                $route = $this->routeResolver
                    ->resolveRoute($routeIdentifier)
                    ->prepare($routeArguments);
                return $request->withAttribute(RouteContext::ROUTE, $route);

            case RoutingResults::NOT_FOUND:
                throw new HttpNotFoundException($request);

            case RoutingResults::METHOD_NOT_ALLOWED:
                $exception = new HttpMethodNotAllowedException($request);
                $exception->setAllowedMethods($routingResults->getAllowedMethods());
                throw $exception;

            default:
                throw new RuntimeException('An unexpected error occurred while performing routing.');
        }
    }

    /**
     * Resolves the route from the given request
     */
    protected function resolveRoutingResultsFromRequest(ServerRequestInterface $request): RoutingResults
    {
        return $this->routeResolver->computeRoutingResults(
            $request->getUri()->getPath(),
            $request->getMethod()
        );
    }
}

View on GitHub (pinned to 80900fb39c)

When it happens

Trigger: Thrown at Slim/Middleware/RoutingMiddleware.php:84 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of slimphp/Slim@80900fb39c (2026-08-21). Data as JSON: /api/errors/2cb23b65814dc20e. Report an issue: GitHub.