Automate Shopify Order Emails & PDF Invoices Using TemplateMaster API + Webhooks

When a new order is created in Shopify, many merchants want to automatically:

Generate a PDF invoice
Send a confirmation email
Store or archive the document
Trigger backend processes

But doing this manually — or building your own PDF generation engine — is complex and time-consuming.

In this article, I’ll show you how to integrate Shopify Webhooks with the TemplateMaster API to automatically send invoices and emails whenever a new order is created.

This works with any backend language (C#, Node.js, Python, PHP…).

🧩 What is TemplateMaster?

TemplateMaster is a SaaS designed for developers and businesses who need:

📝 HTML/CSS template editor
📄 PDF generation via API
✉️ Email sending API
🔐 API key protection
🧩 JSON-based dynamic rendering
🗂️ Storage + versioning of templates

It is perfect for invoices, receipts, order confirmations, shipping docs, etc.

👉 Try it here: https://templatemaster.fr

📦 Shopify Webhook + TemplateMaster Workflow

1. Customer places an order ⬇️
2. Shopify triggers the orders/create webhook ⬇️
3. Your server receives the webhook ⬇️
4. Your server calls TemplateMaster API to:

Generate a PDF invoice
Send an email to the customer (with PDF attached)

⬇️

1. Shopify customer receives your customized invoice

1. Configure the Shopify Webhook

In Shopify Admin:

Settings → Notifications → Webhooks → Create Webhook

Event: Order creation (orders/create)
Format: JSON
URL: Your API endpoint (e.g. https://your-server.com/webhooks/shopify/order-created)

Shopify will POST the full order JSON to your server.

2. Example of Webhook Receiver (Node.js)

This endpoint receives the Shopify order JSON and generates a PDF invoice through TemplateMaster.

import express from "express";
import axios from "axios";

const app = express();
app.use(express.json());

app.post("/webhooks/shopify/order-created", async (req, res) => {
  const order = req.body;

  try {
    // Call TemplateMaster to generate a PDF + send email
    await axios.post(
      "https://api.templatemaster.fr/generate/pdf-email",
      {
        templateId: "your-invoice-template-id",
        data: order, // You can remap fields if needed
        email: {
          to: order.email,
          subject: `Invoice for Order #${order.name}`
        }
      },
      {
        headers: {
          "X-API-KEY": process.env.TM_API_KEY
        }
      }
    );

    res.status(200).send("OK");
  } catch (err) {
    console.error(err);
    res.status(500).send("Error");
  }
});

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

3. Example in C# (.NET)

using System.Net.Http;
using System.Text;

var client = new HttpClient();
client.DefaultRequestHeaders.Add("X-API-KEY", "YOUR_API_KEY");

app.MapPost("/webhooks/shopify/order-created", async (Order order) =>
{
    var requestBody = new
    {
        templateId = "your-invoice-template-id",
        data = order,
        email = new
        {
            to = order.email,
            subject = $"Invoice for Order {order.name}"
        }
    };

    var json = System.Text.Json.JsonSerializer.Serialize(requestBody);
    var content = new StringContent(json, Encoding.UTF8, "application/json");

    await client.PostAsync("https://api.templatemaster.fr/generate/pdf-email", content);

    return Results.Ok();
});

4. Template Structure (Invoice Example)

Inside your TemplateMaster HTML template, simply use JSON placeholders:

<h1>Invoice – Order {{name}}</h1>

<p>Date: {{created_at}}</p>
<p>Customer: {{customer.first_name}} {{customer.last_name}}</p>

<table>
  <tr>
    <th>Item</th>
    <th>Qty</th>
    <th>Price</th>
  </tr>

  {{#each line_items}}
  <tr>
    <td>{{title}}</td>
    <td>{{quantity}}</td>
    <td>{{price}}</td>
  </tr>
  {{/each}}
</table>

<p>Total: {{total_price}} {{currency}}</p>

TemplateMaster automatically applies your CSS and returns a beautiful PDF.

5. Bonus Features You Can Add

✔️ Send emails to the store owner
✔️ Send packing slips to warehouse staff
✔️ Add customer notes, discount codes, fulfillment info
✔️ Save PDFs to your storage (S3, Azure, etc.)
✔️ Use multiple templates depending on order type

🎉 Conclusion

With just a few lines of code, you can fully automate:

PDF invoice generation
Order confirmation emails
Document storage
Multi-store workflows

Using Shopify Webhooks + TemplateMaster API is a powerful way to build scalable, automated document flows without maintaining your own rendering engine.

👉 Try it now: https://templatemaster.fr