[d565449] | 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
|
---|