Package Exports

fast-safe-stringify

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (fast-safe-stringify) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

fast-safe-stringify

Safely and quickly serialize JavaScript objects

Detects circular dependencies instead of throwing (as per usual JSON.stringify usage)

Usage

var safeStringify = require('fast-safe-stringify')
var o = {a: 1}
o.o = o

console.log(safeStringify(o))  // '{"a":1,"o":"[Circular]"}'
console.log(JSON.stringify(o)) //<-- throws

Benchmarks

The json-stringify-safe module supplies similar functionality with more info and flexibility.

Although not JSON, the core util.inspect method can be used for similar purposes (e.g. logging) and also handles circular references.

Here we compare fast-safe-stringify with these alternatives:

inspectBench*10000: 179.608ms
jsonStringifySafeBench*10000: 30.099ms
fastSafeStringifyBench*10000: 19.965ms

inspectCircBench*10000: 220.763ms
jsonStringifyCircSafeBench*10000: 39.115ms
fastSafeStringifyCircBench*10000: 29.444ms

inspectDeepBench*10000: 2231.148ms
jsonStringifySafeDeepBench*10000: 880.177ms
fastSafeStringifyDeepBench*10000: 230.209ms

inspectDeepCircBench*10000: 2221.848ms
jsonStringifySafeDeepCircBench*10000: 922.314ms
fastSafeStringifyDeepCircBench*10000: 236.024ms

Protip

Whether you're using fast-safe-stringify or json-stringify-safe if your use case consists of deeply nested objects without circular references the following pattern will give you best results:

var fastSafeStringify = require('fast-safe-stringify')
function tryStringify (obj) {
  try { return JSON.stringify(obj) } catch (_) {}
}
var str = tryStringify(deep) || fastSafeStringify(deep)

If you're likely to be handling mostly shallow or one level nested objects, this same pattern will degrade performance - it's entirely dependant on use case.

JSON.stringify options

JSON.stringify's replacer and space options are not supported. Any value other than 0 for space halves the speed, and providing a replacer function can result in a segfault. Given that the primary focus of this serializer is speed, the trade offs for supporting these options are not desirable.

Acknowledgements

License

MIT