PDF Generation with PDFKit

Setup

npm install pdfkit

Basic PDF

const PDFDocument = require('pdfkit');
const fs = require('fs');

const doc = new PDFDocument();

doc.pipe(fs.createWriteStream('output.pdf'));

doc.fontSize(25).text('Hello World!', 100, 100);

doc.addPage()
   .fontSize(15)
   .text('Second page', 100, 100);

doc.end();

Invoice Example

function generateInvoice(invoice, res) {
  const doc = new PDFDocument({ margin: 50 });
  
  doc.pipe(res);
  
  doc.fontSize(20).text('INVOICE', 50, 50);
  doc.fontSize(10).text(`Invoice #: ${invoice.id}`, 50, 80);
  
  doc.moveTo(50, 120).lineTo(550, 120).stroke();
  
  doc.fontSize(12).text('Bill To:', 50, 140);
  doc.fontSize(10).text(invoice.customer.name, 50, 160);
  
  doc.end();
}

app.get('/invoice/:id', async (req, res) => {
  const invoice = await Invoice.findById(req.params.id);
  
  res.setHeader('Content-Type', 'application/pdf');
  res.setHeader('Content-Disposition', `attachment; filename=invoice-${invoice.id}.pdf`);
  
  generateInvoice(invoice, res);
});

Key Takeaway

PDFKit creates PDFs programmatically. Pipe to response for downloads. Good for invoices and reports.