Multer: Unexpected end of form-CodePudding

Currently unable to get a basic multer text form example working.

'use strict';

const express = require('express');
const app = express();

const PORT = 8077;
app.listen(PORT, () => {
  console.info(`Started http://localhost:${PORT} (PID: ${process.pid})`);
  const multer = require('multer');
  const upload = multer();
  app.post('/post', upload.none(), (req, res) => {
    console.log("POST");
    console.log(req.body);
  });
  postSomething();
});

async function postSomething() {
  const fetch = require('node-fetch');
  let res = await fetch('http://localhost:8077/post', {
    method: 'POST',
    credentials: 'include',
    headers: {'Content-type': 'multipart/form-data; boundary=abcde12345' },
    body: `--abcde12345
Content-Disposition: form-data; name="id"
Content-Type: text/plain
foo
--abcde12345--`
  });
  console.log(res.status);
}

What is the problem with parsing this body?

Error: Unexpected end of form
    at Multipart._final (C:\projects\bar\node_modules\busboy\lib\types\multipart.js:588:17)
    at callFinal (node:internal/streams/writable:696:27)
    at prefinish (node:internal/streams/writable:725:7)
    at finishMaybe (node:internal/streams/writable:735:5)
    at Multipart.Writable.end (node:internal/streams/writable:633:5)
    at IncomingMessage.onend (node:internal/streams/readable:693:10)
    at Object.onceWrapper (node:events:627:28)
    at IncomingMessage.emit (node:events:525:35)
    at endReadableNT (node:internal/streams/readable:1358:12)
    at processTicksAndRejections (node:internal/process/task_queues:83:21)

CodePudding user response：

The solution is to use \r\n instead of implicit line endings as well as ensuring that there is an empty line before each value.

'use strict';

const express = require('express');
const app = express();

const PORT = 8077;
app.listen(PORT, () => {
  console.info(`Started http://localhost:${PORT} (PID: ${process.pid})`);
  const multer = require('multer');
  const upload = multer();
  app.post('/post', upload.none(), (req, res) => {
    console.log("POST");
    console.log(req.body?.id);
  });
  postSomething();
});

async function postSomething() {
  const fetch = require('node-fetch');
  let res = await fetch('http://localhost:8077/post', {
    method: 'POST',
    credentials: 'include',
    headers: {'Content-type': 'multipart/form-data; boundary=abcde12345' },
    body: `--abcde12345\r\nContent-Disposition: form-data; name="id"\r\nContent-Type: text/plain\r\n\r\nfoo\r\n--abcde12345--`
  });
  console.log(res.status);
}

So basically my mistakes were:

Not using CRLF
Forgetting a newline before foo
Using the wrong boundary (the header has one -- less than the body)

CodePudding user response：

use body-parser middleware for this issue and will resolve your problem

const bodyParser = require('body-parser')
// ...
app.use(bodyParser())