GST Library

A simple Node.js library for calculating GST (Goods and Services Tax) and generating invoices.

Installation

npm install gst-lib

Usage

const { calculateGST, generateInvoice, createPDFInvoice } = require('gst-lib');

// Calculate GST
const gstResult = calculateGST(1000, 18);
console.log(gstResult); // { amount: 1000, gstRate: 18, cgst: 90, sgst: 90, totalAmount: 1180 }

// Generate Invoice
const items = [
  { name: "Shirt", price: 500, qty: 2 },
  { name: "Shoes", price: 1000, qty: 1 }
];
const invoice = generateInvoice(items, { taxRate: 18, discount: 10 });
console.log(invoice);

// Create PDF Invoice
createPDFInvoice(invoice, "invoice.pdf");

API

calculateGST(amount, gstRate)

Calculates GST for a given amount and rate.

• amount: Number - The base amount
• gstRate: Number - The GST rate in percentage
• Returns: Object with amount, gstRate, cgst, sgst, totalAmount

generateInvoice(items, options)

Generates an invoice from items.

• items: Array of objects with name, price, qty
• options: Object with taxRate (default 18) and discount (default 0)
• Returns: Invoice object

createPDFInvoice(data, fileName)

Creates a PDF invoice.

• data: Invoice data object
• fileName: Output file name (default "invoice.pdf")

License

MIT