Node.js Connect中间件限制不起作用

Question

I have a problem server:

var connect = require('connect');
var http = require('http');

var app = connect()
.use(connect.limit('32kb'))
.use(connect.urlencoded())
.use(connect.json())
.use(function(req, res){
    console.log('yo');
    res.end('hello\n');
});

http.createServer(app).listen(3000);

client:

var http = require('http');

var req = http.request({
method: 'POST',
port: 3000,
headers: {
    'Content-Type': 'application/json'
}
});

req.write('[');
var n = 30000000;
while (n--) {
req.write('"foo",');
}
req.write('"bar"]');
req.end();

Connect's middleware limit not "limiting" size of json. I know that it will deprecated, but instead Express framework what can i use to limit a size of requests?

Answer 1

do this instead:

.use(connect.urlencoded({
  limit: '32kb'
}))
.use(connect.json({
  limit: '32kb'
}))

or just:

.use(connect.bodyParser({
  limit: '32kb'
})

you can still write to req , but that doesn't necessarily mean the server will receive those bytes. if you check the response and it isn't a 4xx error, then it's a bug.

EDIT:

req.once('response', function (res) {
  assert.equal(res.statusCode, 413)
})
.write(new Buffer(123123123213223122))
.end()

Answer 2

the limit middleware checks the header Content-Length of request message only while there's no such header out of your HTTP POST request.

You can verify this by using:

var app = connect()
.use(connect.limit('32kb'))
.use(connect.urlencoded())
.use(connect.json())
.use(function(req, res){
  console.log(req.headers);
  console.log('yo');
  res.end('hello\n');
});

You can test the limit middle via this code:

var http = require('http');

var req = http.request({
  method: 'POST',
  port: 3000,
  headers: {
    'Content-Type': 'application/json',
    'Content-Length': 40 * 1024
  }
});

BTW: you can check how the limit middleware is tested: https://github.com/senchalabs/connect/blob/master/test/limit.js