polling-jsonp.js
1.72 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.JSONP = void 0;
const polling_1 = require("./polling");
const qs = require("querystring");
const rDoubleSlashes = /\\\\n/g;
const rSlashes = /(\\)?\\n/g;
class JSONP extends polling_1.Polling {
/**
* JSON-P polling transport.
*
* @api public
*/
constructor(req) {
super(req);
this.head = "___eio[" + (req._query.j || "").replace(/[^0-9]/g, "") + "](";
this.foot = ");";
}
/**
* Handles incoming data.
* Due to a bug in \n handling by browsers, we expect a escaped string.
*
* @api private
*/
onData(data) {
// we leverage the qs module so that we get built-in DoS protection
// and the fast alternative to decodeURIComponent
data = qs.parse(data).d;
if ("string" === typeof data) {
// client will send already escaped newlines as \\\\n and newlines as \\n
// \\n must be replaced with \n and \\\\n with \\n
data = data.replace(rSlashes, function (match, slashes) {
return slashes ? match : "\n";
});
super.onData(data.replace(rDoubleSlashes, "\\n"));
}
}
/**
* Performs the write.
*
* @api private
*/
doWrite(data, options, callback) {
// we must output valid javascript, not valid json
// see: http://timelessrepo.com/json-isnt-a-javascript-subset
const js = JSON.stringify(data)
.replace(/\u2028/g, "\\u2028")
.replace(/\u2029/g, "\\u2029");
// prepare response
data = this.head + js + this.foot;
super.doWrite(data, options, callback);
}
}
exports.JSONP = JSONP;