ultra-uuid/index.mjs

A non-duplicate ultra-secure UUID generator using timestamp + extended character set

let lastTime = 0;
let counter = 0;

export function generateUltraUUID(length = 50) {
    const now = Date.now();

    if (now === lastTime) {
        counter++;
    } else {
        counter = 0;
        lastTime = now;
    }

    const timeStr = now.toString();
    const counterStr = counter.toString().padStart(4, "0");
    const pidStr = (typeof process !== "undefined" ? process.pid : 0)
        .toString()
        .padStart(5, "0");

    const prefix = timeStr + counterStr + pidStr;
    const charset =
        "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
    const remainingLength = length - prefix.length;

    let randomStr = "";
    for (let i = 0; i < remainingLength; i++) {
        const index = Math.floor(Math.random() * charset.length);
        randomStr += charset[index];
    }

    const rawUUID = prefix + randomStr;
    const arr = rawUUID.split("");
    for (let i = arr.length - 1; i > 0; i--) {
        const j = Math.floor(Math.random() * (i + 1));
        [arr[i], arr[j]] = [arr[j], arr[i]];
    }
    return arr.join("");
}