Naturally Produced Modules

    json-stable-stringify-pretty

    1.2.0 • Public • Published

    json-stable-stringify

    deterministic version of JSON.stringify() so you can get a consistent hash from stringified results

    You can also pass in a custom comparison function.

    browser support

    build status

    example

    var stringify = require('json-stable-stringify');
    var obj = { c: 8, b: [{z:6,y:5,x:4},7], a: 3 };
    console.log(stringify(obj));

    output:

    {"a":3,"b":[{"x":4,"y":5,"z":6},7],"c":8}
    

    methods

    var stringify = require('json-stable-stringify')

    var str = stringify(obj, opts)

    Return a deterministic stringified string str from the object obj.

    options

    cmp

    If opts is given, you can supply an opts.cmp to have a custom comparison function for object keys. Your function opts.cmp is called with these parameters:

    opts.cmp({ key: akey, value: avalue }, { key: bkey, value: bvalue })

    For example, to sort on the object key names in reverse order you could write:

    var stringify = require('json-stable-stringify');
     
    var obj = { c: 8, b: [{z:6,y:5,x:4},7], a: 3 };
    var s = stringify(obj, function (a, b) {
        return a.key < b.key ? 1 : -1;
    });
    console.log(s);

    which results in the output string:

    {"c":8,"b":[{"z":6,"y":5,"x":4},7],"a":3}
    

    Or if you wanted to sort on the object values in reverse order, you could write:

    var stringify = require('json-stable-stringify');
    
    var obj = { d: 6, c: 5, b: [{z:3,y:2,x:1},9], a: 10 };
    var s = stringify(obj, function (a, b) {
        return a.value < b.value ? 1 : -1;
    });
    console.log(s);
    

    which outputs:

    {"d":6,"c":5,"b":[{"z":3,"y":2,"x":1},9],"a":10}
    

    space

    If you specify opts.space, it will indent the output for pretty-printing. Valid values are strings (e.g. {space: \t}) or a number of spaces ({space: 3}).

    For example:

    var obj = { b: 1, a: { foo: 'bar', and: [1, 2, 3] } };
    var s = stringify(obj, { space: '  ' });
    console.log(s);

    which outputs:

    {
      "a": {
        "and": [
          1,
          2,
          3
        ],
        "foo": "bar"
      },
      "b": 1
    }
    

    replacer

    The replacer parameter is a function opts.replacer(key, value) that behaves the same as the replacer from the core JSON object.

    pretty

    If you specify opts.pretty: true the stringified text will be formatted as Javascript instead of JSON, similar to util.inspect().

    For example:

    var obj = { one: 1, two: { b: 4, a: [2,3] } };
    var s = stringify(obj, { pretty: true });
    console.log(s);

    which outputs:

    {one:1,two:{a:[2,3],b:4}}

    Or if also using space:

    var obj = { one: 1, two: { b: 4, a: [2,3] } };
    var s = stringify(obj, { pretty: true, space: '  ' });
    console.log(s);

    which outputs:

    {
      one: 1,
      two: {
        a: [
          2,
          3
        ],
        b: 4
      }
    }

    sortarrays

    If you specify opts.sortarrays: true all arrays in the output will be sorted. This can be useful in situations where an array is used with the semantics of an unordered collection.

    For example:

    var obj = { one: 1, two: { b: 4, a: [9,3] } };
    var s = stringify(obj, { sortarrays: true });
    console.log(s);

    which outputs:

    {"one":1,"two":{"a":[3,9],"b":4}}

    undef

    By default, if an object has a key whose value is undefined, the key will not be shown in the stringified output. The option {undef: true} will display the key

    For example:

    var obj = { a: 3, z: undefined };
    var s = stringify(obj);
    console.log('Default: ', s);
    var t = stringify(obj, {undef: true});
    console.log('With undef: ', t);

    which outputs:

    Default: {"a":3}
    With undef: {"a":3,z:undefined}

    install

    With npm do:

    npm install json-stable-stringify
    

    license

    MIT

    Install

    npm i json-stable-stringify-pretty

    DownloadsWeekly Downloads

    492

    Version

    1.2.0

    License

    MIT

    Last publish

    Collaborators

    • jimlloyd