I am running into a situation where I need to generate multiple filled PDF forms, I have the data filled out and the 'bytes' file is accessible, but when I attempt to combine the 2 files in their byte representation, nothing happens, the file is overridden and the original is the only thing shown.
What am I doing wrong, this seems like it should be easy.
# don't worry about these, they are filled PDFs in byte form, this works as expected.
pdf1 = PDFFormManager.fill_with_jinja(file=template, data=data)
pdf2 = PDFFormManager.fill_with_jinja(file=template, data={})
# here is the issue
print(len(pdf1), len(pdf2)) # 177354 177354
print(type(pdf1), type(pdf2)) # <class 'bytes'> <class 'bytes'>
print(len(pdf1+ pdf2)) # 354708
# when I return this, I only get the single pdf, not the concatenated one
response = HttpResponse(pdf1+pdf2, content_type=f"application/pdf")
The solution was to take a step back and use pypdf to merge the content from the writer object.
For example:
pdf = PDFFormManager.fill_with_jinja(file=template, data=data)
pdf_merged_buffer = BytesIO()
merger = PdfMerger()
# merger.append(pdf)
merger.append(PdfReader(io.BytesIO(pdf)))
merger.append(PdfReader(io.BytesIO(pdf)))
merger.write(pdf_merged_buffer) # now shows all pages combined!
response = HttpResponse(pdf_merged_buffer.getvalue(), content_type=f"application/pdf")
response['Content-Disposition'] = 'inline; filename="{}"'.format('file.pdf')
response['Content-Length'] = len(response.content)