bserializer/dist/deserialize.js

A TypeScript-based serialization/deserialization library built for exploration and learning.

import { TYPE_CODES } from "./typecodes.js";
const { STRING, NUMBER, BOOLEAN, NULL, ARRAY, OBJECT, FIXED_POINT, UNDEFINED, BIG_FLOAT_STRING, } = TYPE_CODES;
function deserializeArray(buffer, offsetRef) {
    const len = buffer.readUInt32LE(offsetRef.offset);
    offsetRef.offset += 4;
    const result = [];
    for (let i = 0; i < len; i++) {
        result.push(deserializeData(buffer, offsetRef));
    }
    return result;
}
function deserializeObject(buffer, offsetRef) {
    const obj = {};
    const count = buffer.readUInt32LE(offsetRef.offset);
    offsetRef.offset += 4;
    for (let i = 0; i < count; i++) {
        const keyLen = buffer.readUInt32LE(offsetRef.offset);
        offsetRef.offset += 4;
        const key = buffer.toString('utf8', offsetRef.offset, offsetRef.offset + keyLen);
        offsetRef.offset += keyLen;
        obj[key] = deserializeData(buffer, offsetRef);
    }
    return obj;
}
export function deserializeData(buffer, offsetRef = { offset: 0 }) {
    const type = buffer.readUInt8(offsetRef.offset++);
    switch (type) {
        case STRING: {
            const len = buffer.readUInt32LE(offsetRef.offset);
            offsetRef.offset += 4;
            const val = buffer.toString('utf8', offsetRef.offset, offsetRef.offset + len);
            offsetRef.offset += len;
            return val;
        }
        case NUMBER: {
            const val = buffer.readDoubleLE(offsetRef.offset);
            offsetRef.offset += 8;
            return val;
        }
        case BOOLEAN: {
            return !!buffer.readUInt8(offsetRef.offset++);
        }
        case NULL: {
            return null;
        }
        case UNDEFINED: {
            return undefined;
        }
        case ARRAY: {
            return deserializeArray(buffer, offsetRef);
        }
        case OBJECT: {
            return deserializeObject(buffer, offsetRef);
        }
        case FIXED_POINT: {
            const scale = buffer.readUInt32LE(offsetRef.offset);
            offsetRef.offset += 4;
            const raw = buffer.readBigInt64LE(offsetRef.offset);
            offsetRef.offset += 8;
            return Number(raw) / scale;
        }
        case BIG_FLOAT_STRING: {
            const len = buffer.readUInt32LE(offsetRef.offset);
            offsetRef.offset += 4;
            const str = buffer.toString('utf8', offsetRef.offset, offsetRef.offset + len);
            offsetRef.offset += len;
            return parseFloat(str);
        }
        default:
            throw new Error(`Unknown type code: 0x${type.toString(16)}}`);
    }
}