json-stringify-safe is a library that provides a safe way to stringify JavaScript objects with circular references. It helps prevent the common issue of encountering "Converting circular structure to JSON" errors when trying to stringify objects that contain circular references. While json-stringify-safe offers a solution to this problem, there are other libraries in the npm ecosystem that also address circular references when stringifying objects. Here are a couple of alternatives:

• circular-json is a library specifically designed for serializing and deserializing objects with circular references in JavaScript. It provides a simple API for handling circular structures in JSON format.
• flatted is another library that focuses on flattening and unflattening objects with circular references. It offers a way to safely stringify objects without losing the circular references.

For a comparison of circular-json, flatted, and json-stringify-safe, you can check out: Comparing circular-json vs flatted vs json-stringify-safe.

json-stringify-safe

Like JSON.stringify, but doesn't throw on circular references.

Usage

Takes the same arguments as JSON.stringify.

var stringify = require('json-stringify-safe');
var circularObj = {};
circularObj.circularRef = circularObj;
circularObj.list = [ circularObj, circularObj ];
console.log(stringify(circularObj, null, 2));

Output:

{
  "circularRef": "[Circular]",
  "list": [
    "[Circular]",
    "[Circular]"
  ]
}

Details

stringify(obj, serializer, indent, decycler)

The first three arguments are the same as to JSON.stringify. The last is an argument that's only used when the object has been seen already.

The default decycler function returns the string '[Circular]'. If, for example, you pass in function(k,v){} (return nothing) then it will prune cycles. If you pass in function(k,v){ return {foo: 'bar'}}, then cyclical objects will always be represented as {"foo":"bar"} in the result.

stringify.getSerialize(serializer, decycler)

Returns a serializer that can be used elsewhere. This is the actual function that's passed to JSON.stringify.

Note that the function returned from getSerialize is stateful for now, so do not use it more than once.