1
 2/*!
 3 * Connect - json
 4 * Copyright(c) 2010 Sencha Inc.
 5 * Copyright(c) 2011 TJ Holowaychuk
 6 * MIT Licensed
 7 */
 8
 9/**
10 * Module dependencies.
11 */
12
13var utils = require('../utils')
14  , _limit = require('./limit');
15
16/**
17 * noop middleware.
18 */
19
20function noop(req, res, next) {
21  next();
22}
23
24/**
25 * JSON:
26 *
27 * Parse JSON request bodies, providing the
28 * parsed object as `req.body`.
29 *
30 * Options:
31 *
32 *   - `strict`  when `false` anything `JSON.parse()` accepts will be parsed
33 *   - `reviver`  used as the second "reviver" argument for JSON.parse
34 *   - `limit`  byte limit disabled by default
35 *
36 * @param {Object} options
37 * @return {Function}
38 * @api public
39 */
40
41exports = module.exports = function(options){
42  var options = options || {}
43    , strict = options.strict !== false;
44
45  var limit = options.limit
46    ? _limit(options.limit)
47    : noop;
48
49  return function json(req, res, next) {
50    if (req._body) return next();
51    req.body = req.body || {};
52
53    if (!utils.hasBody(req)) return next();
54
55    // check Content-Type
56    if ('application/json' != utils.mime(req)) return next();
57
58    // flag as parsed
59    req._body = true;
60
61    // parse
62    limit(req, res, function(err){
63      if (err) return next(err);
64      var buf = '';
65      req.setEncoding('utf8');
66      req.on('data', function(chunk){ buf += chunk });
67      req.on('end', function(){
68        var first = buf.trim()[0];
69
70        if (0 == buf.length) {
71          return next(utils.error(400, 'invalid json, empty body'));
72        }
73        
74        if (strict && '{' != first && '[' != first) return next(utils.error(400, 'invalid json'));
75        try {
76          req.body = JSON.parse(buf, options.reviver);
77        } catch (err){
78          err.body = buf;
79          err.status = 400;
80          return next(err);
81        }
82        next();
83      });
84    });
85  };
86};