Rejects requests whose body exceeds a configured maximum with 413 Content Too Large (nginx returns 413 here too). OpenSwoole's package_max_length is the transport-level hard cap; this is the configurable application-level limit with the standard 413 response, so legacy code that expects oversized uploads to be refused behaves as it would under nginx/Apache.

The limit accepts a byte count (new BodySizeLimitMiddleware(10_485_760)) or an nginx-style size string ('10m', '512k', '1g').

Content-Length requests: the declared length is checked before the body is read — a fast, zero-copy path that mirrors Apache's ap_h1_body_in_filter pre-read guard.

Chunked / no Content-Length requests: Apache enforces LimitRequestBody against the decoded chunked byte count via the ctx->limit_used accumulator (http_filters.c:671-686). In the OpenSwoole runtime the body is already fully decoded and buffered by the time the PSR-15 middleware stack runs — the Transfer-Encoding: chunked layer is owned by OpenSwoole's C parser and is not re-exposed to PHP. This middleware therefore measures the length of the buffered body string (via $request->getBody()->getSize() or a strlen-equivalent fallback) and enforces the cap on that decoded size. What this covers: any chunked upload that OpenSwoole accepted and decoded into its internal buffer — package_max_length is still the outermost transport guard for bodies so large they never reach PHP at all.

Usage in app.php: $app->addMiddleware(new \ZealPHP\Middleware\BodySizeLimitMiddleware('10m'));