1n-destructure

@1natsie/destructure

A powerful, type-safe, and highly efficient library for the serialisation and deserialisation of structured data into compact binary formats.

Features

• Performance Optimized: Designed for high-speed encoding and decoding.
• Compact Binary Format: Minimal overhead compared to JSON or other text-based formats.
• Type Safe: Full TypeScript support with automatic type inference for your data structures.
• Flexible Schemas: Support for primitives, objects, arrays, tuples, optionals, and custom handlers.
• Cross-Platform: Works in Node.js, Deno, and the browser.

Installation

Via JSR (Recommended for Deno/Modern ESM)

# Deno
deno add jsr:@1natsie/destructure

# Node.js (via npx)
npx jsr add @1natsie/destructure

Via npm/yarn/pnpm

npm install 1n-destructure

Basic Usage

import { encode } from "@1natsie/destructure/encode";
import { decode } from "@1natsie/destructure/decode";
import { string, type Data } from "@1natsie/destructure/schema";

// Define a schema
const userSchema = {
  id: "u32",
  username: string,
  age: "u8",
  tags: ["char", "char", "char"] as const, // Fixed-size tuple
};

// Data to encode (Type-safe!)
const user: Data.Input<typeof userSchema> = {
  id: 1234,
  username: "johndoe",
  age: 30,
  tags: ["A", "B", "C"],
};

// Encode to Uint8Array
const binary = encode(userSchema, user);

// Decode back to object
const decoded = decode(userSchema, binary);
console.log(decoded.username); // "johndoe"

API Documentation

Main Entry Points

encode<T>(schema: T, data: Data.Input<T>): Uint8Array

Serialises data into a Uint8Array based on the provided schema.

decode<T>(schema: T, buffer: Uint8Array): Data.Output<T>

Deserialises a Uint8Array back into structured data based on the schema.

---

Schema Primitives

The following primitive strings can be used in your schemas:

Type	Description	Byte Size
u8, u16, u32	Unsigned Integers (8, 16, 32 bit)	1, 2, 4
i8, i16, i32	Signed Integers (8, 16, 32 bit)	1, 2, 4
f32, f64	Floats (32, 64 bit)	4, 8
char	Single ASCII/UTF-8 character	1

Example:

const s = "u32";
const s2 = "f64";

---

Complex Schema Helpers

array(schema, count?)

Defines an array of a specific schema.

• If count is omitted (or set to -1), the array is dynamic and prefixed with a 4-byte length.
• If count is provided, the array is fixed-size.

import { array } from "@1natsie/destructure/schema";

const dynamicArray = array("u8"); // Length-prefixed
const fixedArray = array("u16", 5); // Exactly 5 elements
const simpleSyntax = "u8[]"; // Equivalent to array("u8")
const fixedSyntax = "u8[10]"; // Equivalent to array("u8", 10)

optional(schema)

Defines a field that may be undefined. Prefixed with a 1-byte boolean flag (0 or 1).

import { optional } from "@1natsie/destructure/schema";

const schema = {
  required: "u32",
  maybe: optional("u16"),
};

string and string.nullTerminated

Handlers for string data.

• string: Prefixed with a 4-byte length. Supports full UTF-8.
• string.nullTerminated: C-style string ending in \0. No length prefix.

import { string } from "@1natsie/destructure/schema";

const schema = {
  normal: string,
  legacy: string.nullTerminated,
};

bytes

Handler for raw Uint8Array data. Prefixed with a 4-byte length.

import { bytes } from "@1natsie/destructure/schema";

const schema = {
  raw: bytes,
};

custom(handler)

Create your own custom serialisation logic.

import { custom } from "@1natsie/destructure/schema";

const dateHandler = custom<Date>({
  encode: (d) => {
    const buf = new Uint8Array(8);
    new DataView(buf.buffer).setBigUint64(0, BigInt(d.getTime()), true);
    return buf;
  },
  decode: (bytes, offset) => {
    const time = bytes.view.getBigUint64(offset, true);
    return { value: new Date(Number(time)), nextOffset: offset + 8 };
  },
  size: () => ({ value: 8, isVariable: false }),
});

---

Objects and Tuples

Objects

Plain objects define key-value structures. Keys are sorted alphabetically during encoding to ensure consistent binary output.

const user = {
  name: string,
  age: "u8",
};

Tuples

Arrays in the schema define fixed-order tuples.

const point = ["f32", "f32", "f32"] as const;

---

Use Cases

1. Network Protocols: Building custom binary protocols for WebSockets or TCP.
2. File Storage: Saving complex state in a compact, easy-to-read binary format.
3. IPC (Inter-Process Communication): Passing data between workers or processes with minimal overhead.
4. Performance Critical Apps: Games or real-time data visualisations where JSON parsing is a bottleneck.

Contributing

Contributions are welcome!

1. Fork the repository.
2. Create a feature branch: git checkout -b feature/my-feature
3. Commit your changes: git commit -am 'Add some feature'
4. Push to the branch: git checkout -b feature/my-feature
5. Submit a pull request.

Please ensure all tests pass by running:

node ./testing/destructure.test.ts

License

MIT Oghenevwegba Obire