Download the files needed to compile a LaTeX paper for SoCG21

download-socg-lipics.py

#!/usr/bin/env python3

"""Downloads all the files necessary to compile a LaTeX paper
as per the instructions of SOCG21."""

import sys
import os
from urllib.request import urlopen
from zipfile import ZipFile

SOCG_WRAPPER_URL = 'http://www.computational-geometry.org/guidelines/socg-lipics-v2019.cls'
SOCG_WRAPPER_FNAME = 'socg-lipics-v2019.cls'
LIPICS_ZIP_URL = 'https://submission.dagstuhl.de/styles/download-tag/lipics/v2019.2/authors/zip'
LIPICS_ZIP_FNAME = 'authors-lipics-v2019.zip'
LIPICS_FILES = """
lipics-v2019.cls
lipics-logo-bw.pdf
cc-by.pdf
orcid.pdf
""".split()


def already_exists(fname):
    return os.path.exists(fname)


def check_and_download(fname, url):
    if already_exists(fname):
        print(fname, 'found', file=sys.stderr)
    else:
        print('downloading', url, file=sys.stderr)
        with urlopen(url) as fp:
            data = fp.read()
        with open(fname, 'wb') as fp:
            fp.write(data)


def get_lipics():
    found = True
    for fname in LIPICS_FILES:
        if not already_exists(fname):
            found = False
            print(fname, 'not found; extraction needed', file=sys.stderr)
            break
    if found:
        print('all lipics files found', file=sys.stderr)
        return

    check_and_download(LIPICS_ZIP_FNAME, LIPICS_ZIP_URL)
    with ZipFile(LIPICS_ZIP_FNAME) as zfp:
        for fname in LIPICS_FILES:
            with zfp.open(fname, 'r') as fp:
                data = fp.read()
            with open(fname, 'wb') as fp:
                fp.write(data)


if __name__ == '__main__':
    check_and_download(SOCG_WRAPPER_FNAME, SOCG_WRAPPER_URL)
    get_lipics()