Very fast deterministic serialization alternative to JSON.stringify.
npm install stable-fast-stringifyconst stringify = require('stable-fast-stringify');
const obj = { c: 1, d: 'foo', b: [{ z: 6, x: 9 }, 8], a: 2 };
console.log(stringify(obj));
// {"a":2,"b":[{"x":4,"y":5,"z":6},8],"c":8}If you would like to also have a very fast safe deterministic alternative see
safe-stable-stringify. It will not throw in case circular structures are
found.
The same as JSON.stringify.
stringify(value[, replacer[, space]])
const stringify = require('stable-fast-stringify')
const o = { b: 1, a: 0 }
console.log(stringify(o))
// '{"a":0,"b":1}'
console.log(JSON.stringify(o))
// '{"b":1,"a":0}'
function replacer(key, value) {
console.log('Key:', stringify(key))
return value
}
const serialized = stringify(o, replacer, 2)
// Key: ""
// Key: "a"
// Key: "b"
console.log(serialized)
// {
// "a": 0,
// "b": 1
// }The only difference to JSON.stringify is that the stringified output is
deterministic. This is done by sorting the keys instead of using the insertion
order.
toJSON, replacer and the spacer work the same
as with the native JSON.stringify.
Currently this is by far the fastest known stable stringify implementation. This is especially important for big objects.
(Lenovo T450s with a i7-5600U CPU using Node.js 8.9.4)
simple: array x 2,362,373 ops/sec ±1.95% (89 runs sampled)
simple: object x 675,612 ops/sec ±0.68% (93 runs sampled)
simple: deep x 18,857 ops/sec ±0.79% (90 runs sampled)
replacer: array x 1,520,677 ops/sec ±0.51% (95 runs sampled)
replacer: object x 562,876 ops/sec ±0.66% (89 runs sampled)
replacer: deep x 17,650 ops/sec ±0.97% (93 runs sampled)
indentation: array x 1,809,830 ops/sec ±5.94% (79 runs sampled)
indentation: object x 503,873 ops/sec ±5.53% (85 runs sampled)
indentation: deep x 16,084 ops/sec ±0.63% (93 runs sampled)Comparing stable-fast-stringify with known alternatives:
json-stringify-deterministic x 6,188 ops/sec ±2.30% (92 runs sampled)
json-stable-stringify x 7,610 ops/sec ±1.14% (92 runs sampled)
faster-stable-stringify x 9,239 ops/sec ±0.65% (86 runs sampled)
fast-json-stable-stringify x 9,537 ops/sec ±1.98% (89 runs sampled)
fast-stable-stringify x 11,270 ops/sec ±1.60% (94 runs sampled)
fast-safe-stringify x 15,516 ops/sec ±0.46% (95 runs sampled)
this x 25,991 ops/sec ±0.64% (85 runs sampled)
JSON.stringify x 44,440 ops/sec ±0.55% (95 runs sampled)Note: JSON.stringify is just used as a baseline comparison and the
fast-safe-stringify comparison uses the modules stable implementation.
Sponsored by nearForm
MIT