Simple Border for FPDF2

SimpleBordersFPDF2.py

from fpdf import FPDF
from fpdf.drawing import Point


class Border:
    top_left = None
    top_right = None

    def __init__(self, pdf, width=0.8):
        self.pdf = pdf
        self.width = width
        self.pdf_margin = pdf.l_margin

    @property
    def start_x(cls):
        return (cls.pdf.w - (cls.pdf.w * cls.width)) / 2
    
    @property
    def end_x(cls):
        return cls.start_x + (cls.pdf.w * cls.width)
    
    def __enter__(self):
        self.pdf.set_left_margin(self.start_x)
        self.top_left = Point(self.start_x, self.pdf.y)
        self.top_right = Point(self.end_x, self.pdf.y)
        self.pdf.line(*self.top_left, *self.top_right)
        return self
    
    def __exit__(self, exc_type, exc_value, traceback):
        self.pdf.line(self.start_x, self.pdf.y, *self.top_left)
        self.pdf.line(self.start_x, self.pdf.y, self.end_x, self.pdf.y)
        self.pdf.line(self.end_x, self.pdf.y, *self.top_right)
        self.pdf.set_left_margin(self.pdf_margin)
        return False


class PDF(FPDF):
    def border(self, *args, **kwargs):
        return Border(self, *args, **kwargs)


"""
Simple borders for FPDF2
Use borders with with statement.
# Caveats:
- Doesn't support page breaks (make sure border fits in one page)
- Doesn't support relative margin modification, will restart after border end.
# Example usage:

```
pdf = PDF()
pdf.add_page()

pdf.set_font("Helvetica", "B", size=10)
pdf.cell(0, 10, "Example border:", align='C')
pdf.ln(10)

with pdf.border(width=0.8) as border:
    pdf.cell(0, None, "This text will be displayed in border")
    pdf.ln(4)
    pdf.cell(0, None, "And this text as well")
    pdf.ln(4)

pdf.cell(0, None, "And here we're again outside the border")

pdf.ln(4)

pdf.output("fpdf2_borders.pdf")
```
"""