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1.0.0 • Public • Published


JSON.stringify/parse for complex data structures

Uncomplex is a library without dependencies for serializing and deserializing JavaScript datastructures that contain complex objects such as class instances. It works be defining so called EntityInterfaces that detect whether they are compatible with a specified substructure, convert it when serializing an object and reconvert it when parsing an object.

Quick Start

Install the package via

yarn add uncomplex

and call the following methods:

import { Uncomplex } from 'uncomplex';

const uncomplex = Uncomplex.new().withEntityInterfaces(...entityInterfaces);
const stringified: string = uncomplex.stringifyObject(object);
const parsed: CustomDataStructure = uncomplex.parseObject(stringified);

You can define a custom EntityInterface by implementing EntityInterface:

export interface UncomplexEntityInterface<Original = any, Simplified extends object = object, SimplifyState extends object = any, ParseState extends object = SimplifyState> {
  entityId: string;
  applicableClasses?: any[];
  isApplicable?: (object: Original) => boolean;
  simplifyObject: (object: Original, key: string | number | undefined, state: Partial<SimplifyState>) => Simplified;
  parseObject: (object: Simplified, key: string | number | undefined, state: Partial<ParseState>) => Original;

Note that either applicableClasses (specifies a list of classes for which instanceof is used to determine whether the class can be mapped by the EntityInterface) or isApplicable must be implemented.

Alternatively, the following EntityInterfaces are implemented and can be imported from the uncomplex library:

  • BigIntEntityInterface: Converts bigint instances
  • DateEntityInterface: Converts Date instances
  • MapEntityInterface: Converts Map instances
  • SymbolEntityInterface: Converts symbol instances

Basic Example

The following example can be found at examples/customDataStructure.ts and can be run via yarn example:customDataStructure.

class Example {
  public param: string;
  constructor(param: string) {
    this.param = param;

export const ExampleEntityInterface: UncomplexEntityInterface<Example, { p: string }> = {
  entityId: 'Example',
  applicableClasses: [Example],
  simplifyObject: object => ({ p: object.param }),
  parseObject: object => new Example(object.p)

const uncomplex = Uncomplex.new().withEntityInterfaces(ExampleEntityInterface);
const example = { ex: new Example('test') };
const asString = uncomplex.stringifyObject(example);

// {"ex":{"p":"test","__uncomplexId":"Example"}}

const parsed = uncomplex.parseObject(asString);
console.log(parsed.ex instanceof Example, parsed.ex.param);
// true 'test'

Example using predefined EntityInterfaces

The following example can be found at examples/nativeDataStructure.ts and can be run via yarn example:nativeDataStructure.

const uncomplex = Uncomplex.new().withEntityInterfaces(
  BigIntEntityInterface, DateEntityInterface, MapEntityInterface, SymbolEntityInterface);

const map = new Map();
map.set('a', 'aa');
map.set('b', 42);

const sym1 = Symbol('a');
const sym2 = Symbol('b');

const example = { bigInt: BigInt(9999999999999), date: new Date(1800000000000), map, sym1, sym2, sym1alt: sym1 };
const asString = uncomplex.stringifyObject(example);

// {
//   "bigInt":{"n":"9999999999999","__uncomplexId":"BigInt"},
//   "date":{"iso":"2027-01-15T08:00:00.000Z","__uncomplexId":"Date"},
//   "map":{"entries":[["a","aa"],["b",42]],"__uncomplexId":"Map"},
//   "sym1":{"id":0,"key":"a","__uncomplexId":"Symbol"},
//   "sym2":{"id":1,"key":"b","__uncomplexId":"Symbol"},
//   "sym1alt":{"id":2,"key":"a","__uncomplexId":"Symbol"}
// }

const parsed = uncomplex.parseObject(asString);
// data structure with recreated instances

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npm i uncomplex

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  • lukasbach