1 | # json-stable-stringify
|
---|
2 |
|
---|
3 | This is the same as https://github.com/substack/json-stable-stringify but it doesn't depend on libraries without licenses (jsonify).
|
---|
4 |
|
---|
5 | deterministic version of `JSON.stringify()` so you can get a consistent hash
|
---|
6 | from stringified results
|
---|
7 |
|
---|
8 | You can also pass in a custom comparison function.
|
---|
9 |
|
---|
10 | [![browser support](https://ci.testling.com/substack/json-stable-stringify.png)](https://ci.testling.com/substack/json-stable-stringify)
|
---|
11 |
|
---|
12 | [![build status](https://secure.travis-ci.org/substack/json-stable-stringify.png)](http://travis-ci.org/substack/json-stable-stringify)
|
---|
13 |
|
---|
14 | # example
|
---|
15 |
|
---|
16 | ``` js
|
---|
17 | var stringify = require('json-stable-stringify');
|
---|
18 | var obj = { c: 8, b: [{z:6,y:5,x:4},7], a: 3 };
|
---|
19 | console.log(stringify(obj));
|
---|
20 | ```
|
---|
21 |
|
---|
22 | output:
|
---|
23 |
|
---|
24 | ```
|
---|
25 | {"a":3,"b":[{"x":4,"y":5,"z":6},7],"c":8}
|
---|
26 | ```
|
---|
27 |
|
---|
28 | # methods
|
---|
29 |
|
---|
30 | ``` js
|
---|
31 | var stringify = require('json-stable-stringify')
|
---|
32 | ```
|
---|
33 |
|
---|
34 | ## var str = stringify(obj, opts)
|
---|
35 |
|
---|
36 | Return a deterministic stringified string `str` from the object `obj`.
|
---|
37 |
|
---|
38 | ## options
|
---|
39 |
|
---|
40 | ### cmp
|
---|
41 |
|
---|
42 | If `opts` is given, you can supply an `opts.cmp` to have a custom comparison
|
---|
43 | function for object keys. Your function `opts.cmp` is called with these
|
---|
44 | parameters:
|
---|
45 |
|
---|
46 | ``` js
|
---|
47 | opts.cmp({ key: akey, value: avalue }, { key: bkey, value: bvalue })
|
---|
48 | ```
|
---|
49 |
|
---|
50 | For example, to sort on the object key names in reverse order you could write:
|
---|
51 |
|
---|
52 | ``` js
|
---|
53 | var stringify = require('json-stable-stringify');
|
---|
54 |
|
---|
55 | var obj = { c: 8, b: [{z:6,y:5,x:4},7], a: 3 };
|
---|
56 | var s = stringify(obj, function (a, b) {
|
---|
57 | return a.key < b.key ? 1 : -1;
|
---|
58 | });
|
---|
59 | console.log(s);
|
---|
60 | ```
|
---|
61 |
|
---|
62 | which results in the output string:
|
---|
63 |
|
---|
64 | ```
|
---|
65 | {"c":8,"b":[{"z":6,"y":5,"x":4},7],"a":3}
|
---|
66 | ```
|
---|
67 |
|
---|
68 | Or if you wanted to sort on the object values in reverse order, you could write:
|
---|
69 |
|
---|
70 | ```
|
---|
71 | var stringify = require('json-stable-stringify');
|
---|
72 |
|
---|
73 | var obj = { d: 6, c: 5, b: [{z:3,y:2,x:1},9], a: 10 };
|
---|
74 | var s = stringify(obj, function (a, b) {
|
---|
75 | return a.value < b.value ? 1 : -1;
|
---|
76 | });
|
---|
77 | console.log(s);
|
---|
78 | ```
|
---|
79 |
|
---|
80 | which outputs:
|
---|
81 |
|
---|
82 | ```
|
---|
83 | {"d":6,"c":5,"b":[{"z":3,"y":2,"x":1},9],"a":10}
|
---|
84 | ```
|
---|
85 |
|
---|
86 | ### space
|
---|
87 |
|
---|
88 | If you specify `opts.space`, it will indent the output for pretty-printing.
|
---|
89 | Valid values are strings (e.g. `{space: \t}`) or a number of spaces
|
---|
90 | (`{space: 3}`).
|
---|
91 |
|
---|
92 | For example:
|
---|
93 |
|
---|
94 | ```js
|
---|
95 | var obj = { b: 1, a: { foo: 'bar', and: [1, 2, 3] } };
|
---|
96 | var s = stringify(obj, { space: ' ' });
|
---|
97 | console.log(s);
|
---|
98 | ```
|
---|
99 |
|
---|
100 | which outputs:
|
---|
101 |
|
---|
102 | ```
|
---|
103 | {
|
---|
104 | "a": {
|
---|
105 | "and": [
|
---|
106 | 1,
|
---|
107 | 2,
|
---|
108 | 3
|
---|
109 | ],
|
---|
110 | "foo": "bar"
|
---|
111 | },
|
---|
112 | "b": 1
|
---|
113 | }
|
---|
114 | ```
|
---|
115 |
|
---|
116 | ### replacer
|
---|
117 |
|
---|
118 | The replacer parameter is a function `opts.replacer(key, value)` that behaves
|
---|
119 | the same as the replacer
|
---|
120 | [from the core JSON object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_native_JSON#The_replacer_parameter).
|
---|
121 |
|
---|
122 | # install
|
---|
123 |
|
---|
124 | With [npm](https://npmjs.org) do:
|
---|
125 |
|
---|
126 | ```
|
---|
127 | npm install json-stable-stringify
|
---|
128 | ```
|
---|
129 |
|
---|
130 | # license
|
---|
131 |
|
---|
132 | MIT
|
---|