When working with PDF files in Python, the fpdf library is a popular choice. It allows you to create PDF documents from scratch or modify existing ones. In this article, we will explore different ways to build a Python class for fpdf.

Option 1: Inheritance

One way to create a Python class for fpdf is by using inheritance. This approach involves creating a new class that inherits from the fpdf.FPDF class. By doing so, we can add our own methods and attributes to customize the functionality of the fpdf library.

from fpdf import FPDF

class MyPDF(FPDF):
    def __init__(self):
        super().__init__()
        # Custom initialization code

    def my_custom_method(self):
        # Custom method implementation

# Usage example
pdf = MyPDF()
pdf.add_page()
pdf.set_font("Arial", size=12)
pdf.cell(200, 10, txt="Hello World", ln=1, align="C")
pdf.output("output.pdf")

In this example, we create a new class called MyPDF that inherits from the FPDF class. We can then add our own methods and attributes to customize the PDF generation process. The usage example demonstrates how to create a PDF document using our custom class.

Option 2: Composition

Another approach to building a Python class for fpdf is through composition. This means creating a separate class that interacts with the fpdf library internally. By doing so, we can encapsulate the fpdf functionality and provide a more user-friendly interface.

from fpdf import FPDF

class MyPDF:
    def __init__(self):
        self.pdf = FPDF()

    def add_page(self):
        self.pdf.add_page()

    def set_font(self, font, size):
        self.pdf.set_font(font, size)

    def add_text(self, text):
        self.pdf.cell(200, 10, txt=text, ln=1, align="C")

    def save(self, filename):
        self.pdf.output(filename)

# Usage example
pdf = MyPDF()
pdf.add_page()
pdf.set_font("Arial", size=12)
pdf.add_text("Hello World")
pdf.save("output.pdf")

In this example, we create a separate class called MyPDF that internally uses the FPDF class. We provide methods such as add_page, set_font, add_text, and save to interact with the fpdf library. The usage example demonstrates how to create a PDF document using our custom class.

Option 3: Wrapper

A third option is to create a wrapper class that provides a simplified interface to the fpdf library. This approach is similar to composition but focuses on abstracting the complexity of the fpdf library even further.

from fpdf import FPDF

class MyPDF:
    def __init__(self):
        self.pdf = FPDF()

    def add_page(self):
        self.pdf.add_page()

    def set_font(self, font, size):
        self.pdf.set_font(font, size)

    def add_text(self, text):
        self.pdf.cell(200, 10, txt=text, ln=1, align="C")

    def save(self, filename):
        self.pdf.output(filename)

# Usage example
def create_pdf():
    pdf = MyPDF()
    pdf.add_page()
    pdf.set_font("Arial", size=12)
    pdf.add_text("Hello World")
    pdf.save("output.pdf")

create_pdf()

In this example, we create a wrapper class called MyPDF that provides a simplified interface to the fpdf library. We also define a separate function called create_pdf that encapsulates the PDF generation process. This allows for a more modular and reusable approach.

After exploring these three options, it is clear that the best approach depends on the specific requirements of your project. If you need fine-grained control over the fpdf library, inheritance might be the best choice. If you prefer a more user-friendly interface, composition or a wrapper class can provide a simpler experience. Consider the complexity of your project and the needs of your users to determine the most suitable option.