Generate a PDF from Raw HTML and Add a Barcode Using Python

4 Minutes Read

This tutorial shows how to:

Generate a barcode image.
Convert raw HTML code into a PDF.
Place the barcode on the generated PDF.

The workflow uses these PDF.co endpoints:

POST /v1/barcode/generate
POST /v1/pdf/convert/from/html
POST /v1/pdf/edit/add

The HTML-to-PDF endpoint accepts raw HTML code. It does not accept an HTML file as the source input. To convert an existing webpage, use the PDF from URL endpoint instead.

IN THIS TUTORIAL

Install the Python Dependency

Prepare the Python Script

Configure the Barcode

Configure the HTML

Position the Barcode

Run the Script

Step 1: Install the Python Dependency

Install the requests package:

python -m pip install requests

Store your PDF.co API key in an environment variable named PDFCO_API_KEY.

Step 2: Prepare the Python Script

Create a file named app.py and add the following code:

import os
import requests

API_KEY = os.environ["PDFCO_API_KEY"]
BASE_URL = "https://api.pdf.co/v1"
OUTPUT_FILE = "document-with-barcode.pdf"

HTML_CONTENT = """
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <style>
        body {
            margin: 40px;
            font-family: Arial, sans-serif;
            color: #222;
        }

        h1 {
            color: #2457a7;
        }
    </style>
</head>
<body>
    <h1>Order Confirmation</h1>
    <p>Thank you for your order.</p>
    <p>Order number: 123456</p>
</body>
</html>
"""


def pdfco_post(endpoint, payload):
    response = requests.post(
        f"{BASE_URL}{endpoint}",
        headers={
            "x-api-key": API_KEY,
            "Content-Type": "application/json"
        },
        json=payload,
        timeout=120
    )
    response.raise_for_status()

    result = response.json()

    if result.get("error"):
        raise RuntimeError(result.get("message", "PDF.co request failed"))

    return result


def generate_barcode():
    return pdfco_post(
        "/barcode/generate",
        {
            "type": "Code128",
            "value": "ORDER-123456",
            "name": "barcode.png",
            "inline": False,
            "async": False
        }
    )


def generate_pdf():
    return pdfco_post(
        "/pdf/convert/from/html",
        {
            "html": HTML_CONTENT,
            "name": "order-confirmation.pdf",
            "paperSize": "Letter",
            "orientation": "Portrait",
            "margins": "20px",
            "printBackground": True,
            "mediaType": "print",
            "async": False
        }
    )


def add_barcode(pdf_url, barcode_url):
    return pdfco_post(
        "/pdf/edit/add",
        {
            "url": pdf_url,
            "name": OUTPUT_FILE,
            "images": [
                {
                    "url": barcode_url,
                    "x": 400,
                    "y": 20,
                    "width": 150,
                    "height": 50,
                    "pages": "0"
                }
            ],
            "async": False
        }
    )


def download_file(file_url):
    response = requests.get(file_url, timeout=120)
    response.raise_for_status()

    with open(OUTPUT_FILE, "wb") as output:
        output.write(response.content)


def main():
    barcode = generate_barcode()
    pdf = generate_pdf()
    final_pdf = add_barcode(pdf["url"], barcode["url"])
    download_file(final_pdf["url"])

    print(f"Generated {OUTPUT_FILE}")


if __name__ == "__main__":
    main()

Step 3: Configure the Barcode

Update these values in generate_barcode():

type: The barcode format, such as Code128, QRCode, or DataMatrix.
value: The information to encode.
name: The temporary barcode-image filename.

See the Barcode Generator API for supported formats.

Step 4: Configure the HTML

Replace HTML_CONTENT with the raw HTML markup that should become the PDF.

The /pdf/convert/from/html endpoint accepts the markup through the html parameter. If your application keeps HTML in a local file, Python may read that file into a string first, but the API still receives raw HTML—not the file itself.

To convert a published webpage, call:

POST /v1/pdf/convert/from/url

and supply its URL. See the PDF from HTML documentation and PDF from URL documentation.

Step 5: Position the Barcode

The images object controls where the barcode appears:

x and y: Position measured from the upper-left corner.
width and height: Barcode dimensions.
pages: Target page. 0 represents the first page.

Use the PDF.co PDF Inspector to determine suitable coordinates.

Step 6: Run the Script

Run:

python app.py

The script generates the barcode and PDF as temporary PDF.co files, places the barcode on the first page, and downloads the completed document as:

document-with-barcode.pdf

PDF.co output URLs are temporary. This script downloads the finished PDF immediately so it remains available locally.

Conclusion

You have generated a PDF from raw HTML and added a barcode using Python. The workflow passes the temporary barcode and PDF URLs directly between PDF.co endpoints, eliminating unnecessary uploads and avoiding unsupported HTML-file conversion.