Official Developer Guide • rackupit.com/pdf/userguide

RackUp PDF API User Guide

Everything you need to integrate automated vector PDF invoices, POS receipts, certificates, reports, and WooCommerce billing into your software.

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Quick Start Guide

RackUp PDF API allows you to convert structured JSON payloads into high-precision vector PDFs in under 30 milliseconds. No headless browser (Puppeteer/Chromium) overhead required.

cURL Quick RequestEndpoint: https://api.rackupit.com/v1/invoice

curl -X POST https://api.rackupit.com/v1/invoice \
  -H "X-API-Key: rackup_demo_key_2026" \
  -H "Content-Type: application/json" \
  -d '{
    "invoiceNumber": "INV-2026-001",
    "currencySymbol": "$",
    "seller": { "name": "RackUp IT Solutions", "email": "[email protected]" },
    "customer": { "name": "Acme Corporation", "email": "[email protected]" },
    "items": [
      { "name": "Managed Cloud VPS Hosting", "unitPrice": 45.00, "quantity": 1 }
    ],
    "payment": { "status": "PAID", "qrData": "https://rackupit.com/pay/001" }
  }' \
  --output invoice.pdf

API Key Authentication & Headers

All production requests require a valid API key passed via request headers. You can use our default public demo key rackup_demo_key_2026 for testing.

Header Format (Recommended)

X-API-Key: your_live_api_key_here

Secondary Header Format

api-key: your_live_api_key_here

POST /v1/invoice

POST

Generates a clean, vector A4 PDF invoice. Supports dynamic currency symbols, line item breakdowns, tax percentage, shipping costs, payment QR codes, hex themes, and custom watermarks.

POST /v1/receipt

POST

Renders compact 80mm thermal POS receipts suitable for retail counters, restaurants, and handheld Bluetooth thermal printers with Code128 barcodes.

POST /v1/certificate

POST

Renders landscape course completion certificates with SVG vector borders, gold seal styling, and embedded verification QR codes.

POST /v1/report

POST

Generates executive financial & system performance reports with KPI metric cards and module breakdown tables.

POST /v1/resume

POST

Generates multi-column professional resumes optimized for ATS parsing with skill tags and work experience timelines.

POST /v1/shipping-label

POST

Generates 4x6 inch thermal shipping labels with 1D Code128 tracking barcodes (UPS/FedEx/DHL compliant).

POST /v1/html-to-pdf

POST

Parses custom HTML/CSS templates with {{variable}} substitution into native vector PDFs.

POST /v1/batch-invoices

POST

Process arrays of up to 100 invoices in a single API call. Returns a combined multi-document PDF stream for batch printing or monthly archival.

WooCommerce PHP Integration

Add this lightweight snippet to your WordPress functions.php file to automatically generate and attach RackUp PDF invoices to completed WooCommerce customer emails:

<?php
// Auto-attach RackUp PDF Invoice to WooCommerce Completed Orders
add_filter('woocommerce_email_attachments', 'rackup_pdf_attach_invoice', 10, 3);

function rackup_pdf_attach_invoice($attachments, $email_id, $order) {
    if ($email_id !== 'customer_completed_order' || !$order) return $attachments;

    $items = [];
    foreach ($order->get_items() as $item) {
        $items[] = [
            'name' => $item->get_name(),
            'unitPrice' => (float)$order->get_item_subtotal($item),
            'quantity' => (int)$item->get_quantity()
        ];
    }

    $body = json_encode([
        'invoiceNumber' => 'INV-' . $order->get_order_number(),
        'currencySymbol' => get_woocommerce_currency_symbol(),
        'seller' => ['name' => get_bloginfo('name')],
        'customer' => ['name' => $order->get_formatted_billing_full_name()],
        'items' => $items,
        'payment' => ['status' => 'PAID', 'qrData' => $order->get_checkout_order_received_url()]
    ]);

    $response = wp_remote_post('https://api.rackupit.com/v1/invoice', [
        'headers' => ['Content-Type' => 'application/json', 'X-API-Key' => 'rackup_demo_key_2026'],
        'body' => $body,
        'timeout' => 15
    ]);

    if (!is_wp_error($response) && wp_remote_retrieve_response_code($response) === 200) {
        $pdf_path = sys_get_temp_dir() . '/invoice_' . $order->get_id() . '.pdf';
        file_put_contents($pdf_path, wp_remote_retrieve_body($response));
        $attachments[] = $pdf_path;
    }

    return $attachments;
}

SDK Code Snippets

Node.js / Axios

const axios = require('axios');
const fs = require('fs');

async function generateInvoice() {
  const response = await axios.post('https://api.rackupit.com/v1/invoice', {
    invoiceNumber: "INV-2026-901",
    currencySymbol: "$",
    seller: { name: "RackUp IT Solutions" },
    customer: { name: "Acme Corp" },
    items: [{ name: "Cloud Server", unitPrice: 50.00 }]
  }, {
    headers: { 'X-API-Key': 'rackup_demo_key_2026' },
    responseType: 'arraybuffer'
  });

  fs.writeFileSync('invoice.pdf', response.data);
  console.log("PDF saved!");
}

curl -X POST https://api.rackupit.com/v1/invoice \ -H "X-API-Key: rackup_demo_key_2026" \ -H "Content-Type: application/json" \ -d '{ "invoiceNumber": "INV-2026-001", "currencySymbol": "$", "seller": { "name": "RackUp IT Solutions", "email": "[email protected]" }, "customer": { "name": "Acme Corporation", "email": "[email protected]" }, "items": [ { "name": "Managed Cloud VPS Hosting", "unitPrice": 45.00, "quantity": 1 } ], "payment": { "status": "PAID", "qrData": "https://rackupit.com/pay/001" } }' \ --output invoice.pdf

<?php // Auto-attach RackUp PDF Invoice to WooCommerce Completed Orders add_filter('woocommerce_email_attachments', 'rackup_pdf_attach_invoice', 10, 3); function rackup_pdf_attach_invoice($attachments, $email_id, $order) { if ($email_id !== 'customer_completed_order' || !$order) return $attachments; $items = []; foreach ($order->get_items() as $item) { $items[] = [ 'name' => $item->get_name(), 'unitPrice' => (float)$order->get_item_subtotal($item), 'quantity' => (int)$item->get_quantity() ]; } $body = json_encode([ 'invoiceNumber' => 'INV-' . $order->get_order_number(), 'currencySymbol' => get_woocommerce_currency_symbol(), 'seller' => ['name' => get_bloginfo('name')], 'customer' => ['name' => $order->get_formatted_billing_full_name()], 'items' => $items, 'payment' => ['status' => 'PAID', 'qrData' => $order->get_checkout_order_received_url()] ]); $response = wp_remote_post('https://api.rackupit.com/v1/invoice', [ 'headers' => ['Content-Type' => 'application/json', 'X-API-Key' => 'rackup_demo_key_2026'], 'body' => $body, 'timeout' => 15 ]); if (!is_wp_error($response) && wp_remote_retrieve_response_code($response) === 200) { $pdf_path = sys_get_temp_dir() . '/invoice_' . $order->get_id() . '.pdf'; file_put_contents($pdf_path, wp_remote_retrieve_body($response)); $attachments[] = $pdf_path; } return $attachments; }