What is Bitperm?

Bitperm is a lightweight and efficient permission management library based on bitwise operations. It allows you to assign and check user permissions using integers, making it extremely fast, compact, and easy to integrate into any Node.js or Express project.

Features

🧩 Bitmask-based permission system

⚡ Super-fast checks using bitwise operations

🧠 Full TypeScript support

🔐 Express middleware for route protection

🪶 Minimal and dependency-free

Installation

npm install bitperm

Usage

• Define your permissions

import { BitPerm } from "bitperm";

export const PERMS = {
  COMMENT_VIEW: 1 << 1,     // 2
  COMMENT_CREATE: 1 << 2,   // 4
  COMMENT_DELETE: 1 << 3,   // 8
};

• Combine permissions for a user

let userPermissions = BitPerm.combine(PERMS.COMMENT_VIEW);
// userPermissions = 2

• Check permissions

BitPerm.has(userPermissions, PERMS.COMMENT_VIEW);   // true

• Add or remove permissions

userPermissions = BitPerm.add(userPermissions, PERMS.COMMENT_DELETE);
userPermissions = BitPerm.remove(userPermissions, PERMS.COMMENT_CREATE);

• List all permissions

BitPerm.list(userPermissions, PERMS); 
// Returns: ['COMMENT_VIEW', 'COMMENT_DELETE']

Express Middleware

Protect routes with required permissions.

import express from "express";
import { BitPerm, requirePermission } from "bitperm";

const app = express();

const PERMS = {
  COMMENT_VIEW: 1 << 1,
  COMMENT_CREATE: 1 << 2,
  COMMENT_DELETE: 1 << 3,
};

// Simulated auth middleware
app.use((req, res, next) => {
  req.user = { id: 1, permission: BitPerm.combine(PERMS.COMMENT_VIEW, PERMS.COMMENT_CREATE) };
  next();
});

app.get("/comments", requirePermission(PERMS.COMMENT_VIEW), (req, res) => {
  res.json({ message: "You can view comments" });
});

app.post("/comments", requirePermission(PERMS.COMMENT_CREATE), (req, res) => {
  res.json({ message: "You can create comments" });
});

app.delete("/comments", requirePermission(PERMS.COMMENT_DELETE), (req, res) => {
  res.json({ message: "You can delete comments" });
});

app.listen(3000, () => console.log("Server running on port 3000"));

Publishing & Maintenance

Increment versions with npm version patch|minor|major#

Build with npm run build

Publish with npm publish