Consuming and cancelling the IncomingMessage stream crashes the server.

[Markyiptw]

I have an endpoint for accepting huge files, so instead of loading them at once into memory, I choose to consume incoming as stream and process it with busboy. The happy path works properly, but the server crashes when I start to do stream error handling:

import { pipeline } from "stream/promises";
import { Busboy } from "@fastify/busboy";
import { HttpBindings } from "@hono/node-server";
import { Hono } from "hono";

const app = new Hono<{ Bindings: HttpBindings }>();

app.post("/", async (c) => {
  const { incoming, outgoing } = c.env;
  const busboy = Busboy({
    headers: incoming.headers,
  });
  busboy.on("file", async (fieldname, file, filename, encoding, mimetype) => {
    busboy.emit("error", new Error("Something bad happened"));
  }
  try {
    await pipeline(incoming, busboy);
    return c.html("never reached, as stream/promises/pipeline will throw on error event");
  } catch (err: Error) {
    outgoing.writeHead(500, { Connection: "close" });
    outgoing.end(err.message);
    return RESPONSE_ALREADY_SENT;
  }
)

The whole server crashes with the above code after responding to the client. The error is caused by https://github.com/nodejs/undici/blob/main/lib/web/fetch/body.js#L191, which basically happen when a disturbed stream is being used to initial a request body (cancelled is considered as disturbed in this case). And since those node apis are out of our control, I wonder if we should

• wrap newRequestFromIncoming with some try catch logic?
• don't initialize the request when RESPONSE_ALREADY_SENT is returned? or at least make req.body empty?
• most importantly, we shouldn't let the whole app crash in any case, app.onError should have caught the error.

Thank you!

[ManuelFernando]

@Markyiptw @yusukebe this snippet of code works but when this endpoint is after a middleware which has await operation. For some unknown reason the requested appears streamed and Busboy is unable to read anything

[ManuelFernando]

the problem came with incoming, instead await pipeline(c.req.raw.body, busboy); resolve the problem

@Markyiptw @yusukebe this snippet of code works but when this endpoint is after a middleware which has await operation. For some unknown reason the requested appears streamed and Busboy is unable to read anything

the problem came with incoming, instead await pipeline(c.req.raw.body, busboy); resolve the problem