Combine with pdfrw¶

fpdf2 cannot parse existing PDF files.

However, other Python libraries can be combined with fpdf2 in order to add new content to existing PDF files.

This page provides several examples of using fpdf2 with pdfrw, a great zero-dependency pure Python library dedicated to reading & writing PDFs, with numerous examples and a very clean set of classes modelling the PDF internal syntax.

Sadly, this library is not maintained anymore, cf. pmaupin/pdfrw issue #232 & sarnold/pdfrw issue #15.

Adding content onto an existing PDF page¶

#!/usr/bin/env python3
# USAGE: ./add_on_page_with_pdfrw.py src_file.pdf dest_file.pdf
import sys
from fpdf import FPDF
from pdfrw import PageMerge, PdfReader, PdfWriter
from pdfrw.pagemerge import RectXObj

IN_FILEPATH = sys.argv[1]
OUT_FILEPATH = sys.argv[2]
ON_PAGE_INDEX = 1
# if True, new content will be placed underneath page (painted first):
UNDERNEATH = False

reader = PdfReader(IN_FILEPATH)
area = RectXObj(reader.pages[0])


def new_content():
    fpdf = FPDF(format=(area.w, area.h), unit="pt")
    fpdf.add_page()
    fpdf.set_font("helvetica", size=36)
    fpdf.text(50, 50, "Hello!")
    reader = PdfReader(fdata=bytes(fpdf.output()))
    return reader.pages[0]


writer = PdfWriter()
writer.pagearray = reader.Root.Pages.Kids
if writer.pagearray[0].Kids:
    writer.pagearray = writer.pagearray[0].Kids
PageMerge(writer.pagearray[ON_PAGE_INDEX]).add(
    new_content(), prepend=UNDERNEATH
).render()
writer.write(OUT_FILEPATH)

Adding a page to an existing PDF¶

#!/usr/bin/env python3
# USAGE: ./add_new_page_with_pdfrw.py src_file.pdf dest_file.pdf
import sys

from fpdf import FPDF
from pdfrw import PdfReader, PdfWriter

IN_FILEPATH = sys.argv[1]
OUT_FILEPATH = sys.argv[2]
NEW_PAGE_INDEX = 1  # set to None to append at the end


def new_page():
    fpdf = FPDF()
    fpdf.add_page()
    fpdf.set_font("helvetica", size=36)
    fpdf.text(50, 50, "Hello!")
    reader = PdfReader(fdata=bytes(fpdf.output()))
    return reader.pages[0]


writer = PdfWriter(trailer=PdfReader(IN_FILEPATH))
writer.addpage(new_page(), at_index=NEW_PAGE_INDEX)
writer.write(OUT_FILEPATH)

This example relies on pdfrw Pull Request #216. Until it is merged, you can install a forked version of pdfrw including the required patch:

pip install git+https://github.com/PyFPDF/pdfrw.git@addpage_at_index

Altering with pdfrw a document generated with fpdf2¶

A document created with fpdf2 can the be edited with pdfrw by passing its .output() to a pdfrw.PdfReader:

import io
from fpdf import FPDF
from pdfrw import PdfReader

pdf = FPDF()
pdf.add_page()
pdf.set_font('times', style='B', size=19)
pdf.text(50, 10, 'Hello World!')

reader = PdfReader(io.BytesIO(pdf.output()))