Generate PDF in Python using pdfkit and Make Available via Flask API Endpoint

Introduction

In this tutorial, you'll learn how to generate a PDF file from HTML using pdfkit in Python and how to serve that PDF through a Flask API endpoint. This process is particularly useful for generating client invoices or other documents that can be easily downloaded.

Step 1: Setting Up Your Environment

Before you begin coding, ensure you have the necessary tools and libraries installed.

1. Install Python: Make sure you have Python installed on your machine. You can download it from the official website.
2. Install Flask: Open your terminal or command prompt and run the following command:

   pip install Flask
   

3. Install pdfkit: This library allows you to convert HTML to PDF. Install it using:

   pip install pdfkit
   

4. Install wkhtmltopdf: This is a prerequisite for pdfkit to function properly. Download it from wkhtmltopdf's official site and install it according to your operating system instructions.

Step 2: Creating the Flask Application

Next, you'll create a simple Flask application that will handle PDF generation.

1. Create a new Python file: Name it app.py or similar.
2. Import necessary libraries:

   from flask import Flask, send_file
   import pdfkit
   

3. Initialize the Flask app:

   app = Flask(__name__)
   

Step 3: Creating the PDF Generation Endpoint

Now, you will set up an endpoint that will generate and serve the PDF.

1. Define the route:

   @app.route('/generate-pdf')
   def generate_pdf():
       # HTML content to convert to PDF
       html_content = '<h1>Your Invoice</h1><p>This is a sample invoice.</p>'
       
       # Generate PDF
       pdf = pdfkit.from_string(html_content, False)
       
       # Send the PDF as a downloadable file
       return send_file(pdf, as_attachment=True, download_name='invoice.pdf', mimetype='application/pdf')
   

2. Run the application:

   if __name__ == '__main__':
       app.run(debug=True)
   

Step 4: Testing the API Endpoint

To test your setup and ensure everything is working:

1. Run your Flask application: In the terminal, navigate to the directory containing your app.py and run:

   python app.py
   

2. Access the endpoint: Open your web browser and go to http://127.0.0.1:5000/generate-pdf. This should trigger a PDF download.

Conclusion

You have successfully created a Flask API that generates and serves a PDF file from HTML content using pdfkit. This setup can be expanded and customized for various applications, such as generating invoices or other documents dynamically based on user input.

Next Steps

• Explore customizing the HTML content to create more complex PDFs.
• Consider integrating this API into a larger application or frontend framework.
• Check out the provided GitHub repository for additional examples and enhancements.