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YaBSON is a library allowing schemaless binary-encoded parsing/serialization of JavaScript data with a generator-based implementation

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YaBSON

YaBSON is a library allowing schemaless binary-encoded parsing/serialization of JavaScript data with a generator-based parser/serializer.

This library is designed to transfer large arbitrary amounts of data into chunks. The main goal is to provide a very simple and easily extensible API and implementation. This also illustrates pedagogically the interest of iterators and generators in JavaScript. Note that the binary encoding is determined by the platform endianness.

Example

import { getParser, getSerializer } from "yabson";
// Deno: import { getParser, getSerializer } from "https://deno.land/x/yabson";
// Browser: import { getParser, getSerializer } from "https://unpkg.com/yabson";

// `object` is the data to serialize
const object = {
  array: [
    1,
    2,
    3.1415927,
    true,
    undefined,
    null,
    NaN,
    42n,
    "string",
  ],
  [Symbol("symbol")]: "symbol",
  typedArray: new Uint8Array([1, 2, 3]),
  misc: {
    date: new Date(),
    error: new Error("error"),
    regExp: /test/gi,
  },
  map: new Map([["key", "value"], [42, { value: "result" }]]),
  set: new Set([1, 2, 3]),
  stringObject: new String("abc"),
  numberObject: new Number(123),
  booleanObject: new Boolean(true),
  arrayBuffer: new Uint16Array([1, 2, 3]).buffer,
};
// Create empty slots in `object.array`
object.array[12] = 12;
// Add a circular reference
object.map.set(object.array, object);
// Add a property to a native object
object.numberObject.myProperty = "propertyValue";

// `chunkSize` (optional) is the max. size in bytes of `chunk` in the for-of loop below
const serializer = getSerializer(object, { chunkSize: 16 });
const parser = getParser();

let result;
// `chunk` is a Uint8Array of binary encoded data
for (const chunk of serializer) {
  // Parse immediately binary data
  result = parser.next(chunk);
}
// Display a deep clone of `object`
console.log(result.value);

Test it on JSFiddle: https://jsfiddle.net/np4581x2

Example with a custom type

import {
  getParser,
  getSerializer,
  parseString,
  registerType,
  serializeString,
} from "yabson";

// Custom type class
class CustomType {
  constructor(name) {
    this.name = name;
  }
}

// Register the custom type
registerType(serializeCustomType, parseCustomType, testCustomType);

function* serializeCustomType(data, customType) {
  // Delegate serialization to `serializeString` from yabson
  yield* serializeString(data, customType.name);
}

function* parseCustomType(data) {
  // Delegate parsing to `parseString` from yabson
  const name = yield* parseString(data);
  return new CustomType(name);
}

function testCustomType(value) {
  return value instanceof CustomType;
}

// Run test
const array = [
  new CustomType("first"),
  new CustomType("second"),
];

const serializer = getSerializer(array);
const parser = getParser();

let result;
for (const chunk of serializer) {
  result = parser.next(chunk);
}
// Display a deep clone of `array`
console.log(result.value);

Install

npm install https://www.npmjs.com/package/yabson