bornhack-website/src/utils/pdf.py
2019-07-09 10:38:14 +02:00

69 lines
2 KiB
Python

import logging
import io
import os
from django.contrib.auth.models import AnonymousUser
from wkhtmltopdf.views import PDFTemplateResponse
from PyPDF2 import PdfFileWriter, PdfFileReader
from django.test.client import RequestFactory
from django.conf import settings
logger = logging.getLogger("bornhack.%s" % __name__)
def generate_pdf_letter(filename, template, formatdict):
logger.debug("Generating PDF with filename %s and template %s" % (filename, template))
# conjure up a fake request for PDFTemplateResponse
request = RequestFactory().get("/")
request.user = AnonymousUser()
request.session = {}
# produce text-only PDF from template
pdfgenerator = PDFTemplateResponse(
request=request,
template=template,
context=formatdict,
cmd_options={"margin-top": 50, "margin-bottom": 50},
)
textonlypdf = io.BytesIO()
textonlypdf.write(pdfgenerator.rendered_content)
# create a blank pdf to work with
finalpdf = PdfFileWriter()
# open the text-only pdf
pdfreader = PdfFileReader(textonlypdf)
# get watermark from watermark file
watermark = PdfFileReader(
open(
os.path.join(
settings.STATICFILES_DIRS[0], "pdf", settings.PDF_LETTERHEAD_FILENAME
),
"rb",
)
)
# add the watermark to all pages
for pagenum in range(pdfreader.getNumPages()):
page = watermark.getPage(0)
try:
page.mergePage(pdfreader.getPage(pagenum))
except ValueError:
# watermark pdf might be broken?
return False
# add page to output
finalpdf.addPage(page)
# save the generated pdf to the archive
fullpath = os.path.join(settings.PDF_ARCHIVE_PATH, filename)
with open(fullpath, "wb") as fh:
finalpdf.write(fh)
logger.info("Saved pdf to archive: %s" % fullpath)
returnfile = io.BytesIO()
finalpdf.write(returnfile)
return returnfile