handle circular references when stringifying and parsing

  • jsan

Downloads in past


9113.1.142 years ago9 years agoMinified + gzip package size for jsan in KB


Build Status

JavaScript "All The Things" Notation

Easily stringify and parse any object including objects with circular references, self references, dates, regexes, undefined, errors, and even functions 1, using the familar parse and stringify methods.
There are two ways to use this library, the first is to be able to serialize without having to worry about circular references, the second way is be able to handle dates, regexes, errors, functions 1, errors, and undefined (normally JSON.stringify({ u: undefined }) === '{}')
The usage reflect these two approaches. If you just want to be able to serialize an object then use jsan.stringify(obj), if you want to JSON all the things then use it like jsan.stringify(obj, null, null, true), the first three arguments are the same as JSON.stringify (yup, JSON.stringify takes three arguments)
Note that jsan.stringify(obj, null, null, true) will also deal with circular references


var jsan = require('jsan');

var obj = {};
obj['self'] = obj;
obj['sub'] = {};
obj['sub']['subSelf'] = obj['sub'];
obj.now = new Date(2015, 0, 1);

var str = jsan.stringify(obj);
str === '{"self":{"$jsan":"$"},"sub":{"subSelf":{"$jsan":"$.sub"}},"now":"2015-01-01T05:00:00.000Z"}'; // true
var str2 = jsan.stringify(obj, null, null, true);
str2 === '{"self":{"$jsan":"$"},"sub":{"subSelf":{"$jsan":"$.sub"}},"now":{"$jsan":"d1420088400000"}}'; // true

var newObj1 = jsan.parse(str);
newObj1 === newObj1['self']; // true
newObj1['sub']['subSelf'] === newObj1['sub']; // true
typeof newObj1.now === 'string'; // true

var newObj2 = jsan.parse(str2);
newObj2 === newObj2['self']; // true
newObj2['sub']['subSelf'] === newObj2['sub']; // true
newObj2.now instanceof Date; // true


This ulitilty has been heavily optimized and performs as well as the native JSON.parse and JSON.stringify, for usages of jsan.stringify(obj) when there are no circular references. It does this by first try { JSON.stringify(obj) } and only when that fails, will it walk the object. Because of this it won't property handle self references that aren't circular by default. You can work around this by passing false as the fourth argument, or pass true and it will also handle dates, regexes, undefeined, errors, and functions
var obj = { r: /test/ };
var subObj = {};
obj.a = subObj;
obj.b = subObj;
var str1 = jsan.stringify(obj) // '{"r":{},a":{},"b":{}}'
var str2 = jsan.stringify(obj, null, null, false) // '{"r":{},"a":{},"b":{"$jsan":"$.a"}}'
var str3 = jsan.stringify(obj, null, null, true) // '{"r":{"$jsan":"r,test"},"a":{},"b":{"$jsan":"$.a"}}'
You can't execute the functions after stringify() and parse(), they are just functions that throw which have a toString() method similar to the original function

Advance Usage

You can specify how and what should be handled by passing an object as the fourth argument:
var obj = { u: undefined, r: /test/, f: function bar() {} };
var str = jsan.stringify(obj, null, null, { undefined: true, function: true }); // '{"u":{"$jsan":"u"},"r":{},"f":{"$jsan":"ffunction bar() { /* ... */ }"}}'

The function property of options can also take a function which will be used as the function stringifyer:
var obj = { u: undefined, r: /test/, f: function(x) { return x + 1 } };
var str = jsan.stringify(obj, null, null, {
  undefined: true,
  function: function(fn) { return fn.toString() }
str === '{"u":{"$jsan":"u"},"r":{},"f":{"$jsan":"ffunction (x) { return x + 1 }"}}'; // true