Invoice Generation Project

Overview

This project is a Node.js-based invoice generator that takes input data (seller, buyer, item details, etc.) and produces a formatted PDF invoice. It uses Handlebars for templating and html-pdf to generate a PDF document from the rendered HTML.

Features

• Accepts detailed invoice data including seller, buyer, item descriptions, and taxes.
• Generates a well-formatted PDF invoice.
• Supports calculations for CGST, SGST, and IGST taxes based on the place of supply.
• Customizable invoice template using Handlebars.

Prerequisites

• Node.js (v14+)
• npm (v6+)

Installation

1. Clone the repository:

   git clone <repository-url>
   cd <repository-folder>

2. Install the dependencies:

   npm install

Usage

1. Define your invoice data in sampleData format:

   const sampleData: InvoiceData = {
     sellerDetails: {
       name: "Acme Corp",
       address: "123 Business Rd",
       city: "Metropolis",
       state: "CA",
       pincode: "90210",
       panNo: "ABCDE1234F",
       gstRegistrationNo: "GST123456789",
     },
     placeOfSupply: "CA",
     billingDetails: {
       name: "John Doe",
       address: "456 Customer Ave",
       city: "Metropolis",
       state: "CA",
       pincode: "90211",
       stateUTCode: "CA",
     },
     shippingDetails: {
       name: "Jane Smith",
       address: "789 Delivery St",
       city: "Metropolis",
       state: "CA",
       pincode: "90212",
       stateUTCode: "CA",
     },
     placeOfDelivery: "CA",
     orderDetails: {
       orderNo: "ORD123456",
       orderDate: new Date("2024-09-01"),
     },
     invoiceDetails: {
       invoiceNo: "INV123456",
       invoiceDate: new Date("2024-09-05"),
     },
     reverseCharge: false,
     itemDetails: [
       {
         description: "Widget A",
         unitPrice: 100,
         quantity: 2,
         discount: 10,
         netAmount: 190,
         taxType: "CGST + SGST",
         cgstAmount: 17.1,
         sgstAmount: 17.1,
         igstAmount: 0,
         taxAmount: 34.2,
         totalAmount: 224.2,
       },
       {
         description: "Widget B",
         unitPrice: 200,
         quantity: 1,
         discount: 20,
         netAmount: 180,
         taxType: "CGST + SGST",
         cgstAmount: 16.2,
         sgstAmount: 16.2,
         igstAmount: 0,
         taxAmount: 32.4,
         totalAmount: 212.4,
       },
     ],
   };

2. Generate the invoice:

   generateInvoice(sampleData)
     .then(() => {
       console.log(`Invoice generated successfully!`);
     })
     .catch((error) => {
       console.error(`Error generating invoice`, error);
     });

3. The generated PDF will be saved as invoice.pdf in the project root.

Project Structure

.
├── src/
│   ├── templates/
│   │   └── invoice_template.hbs     # Handlebars template for the invoice
│   ├── invoice_generator.ts         # Main logic for invoice generation
│   └── index.ts                     # Entry point for generating invoices
├── public/
│   └── image.png                    # Company logo used in the invoice
├── README.md                        # Documentation
├── package.json                     # Project configuration and dependencies
└── invoice.pdf                      # Generated PDF (output)