optools/arch/relchk.py
2018-07-22 20:31:05 -04:00

82 lines
2.7 KiB
Python
Executable File

#!/usr/bin/env python3
import configparser
import hashlib
import os
import re
from bs4 import BeautifulSoup
from urllib.parse import urljoin, urlparse
from urllib.request import urlopen
try:
import lxml
htmlparser = 'lxml'
except ImportError:
htmlparser = 'html.parser'
cfgpath = os.path.abspath(os.path.expanduser(
'~/.config/optools/relchk/arch.ini'))
cfg = configparser.ConfigParser()
cfg['arch'] = {'url': 'https://arch.mirror.square-r00t.net/iso/latest/',
'path': '/boot/iso/arch.iso',
'hashtype': 'sha1',
'hashurl': (
'https://arch.mirror.square-r00t.net/iso/latest/sha1sums.txt')
}
if not os.path.isfile(cfgpath):
os.makedirs(os.path.dirname(cfgpath), exist_ok = True)
with open(cfgpath, 'w') as f:
cfg.write(f)
else:
cfg.read(cfgpath)
cfg['arch']['path'] = os.path.abspath(os.path.expanduser(cfg['arch']['path']))
# We need the hashes first. We'll pop them into memory,
# no need to save locally.
# Must be in GNU checksum format (i.e. "<HASH> <FILENAME>\n").
hashes = {}
if 'hashurl' in cfg['arch']:
with urlopen(cfg['arch']['hashurl']) as h:
for i in h.read().decode('utf-8').splitlines():
line = [x.strip() for x in i.split()]
hashes[os.path.basename(line[1])] = line[0]
chksum = hashlib.new(cfg['arch']['hashtype'])
# Now we (try to) get a list of files available for download. We're looking
# for .iso or .img files. Compressed images not currently supported; TODO.
exts = re.compile('.*\.(iso|img)$', re.IGNORECASE)
imgfiles = []
with urlopen(cfg['arch']['url']) as u:
dlsoup = BeautifulSoup(u.read().decode('utf-8'), htmlparser)
for a in dlsoup.find_all('a'):
if a['href']:
if exts.search(a['href']):
if not urlparse(a['href']).netloc:
imgfiles.append(urljoin(cfg['arch']['url'], a['href']))
else:
imgfiles.append(a['href'])
if not imgfiles:
raise RuntimeError('Could not find any ISO or IMG files at {0}'.format(
cfg['arch']['url']))
# Not foolproof, but will handle standard Arch ISO mirrors just fine.
imgfiles.sort()
iso = imgfiles[0]
# Now we get the existing file (if it exists) and grab the hash (if we have
# one fetched).
up2date = False
if os.path.isfile(cfg['arch']['path']):
_fname = os.path.basename(iso)
if _fname in hashes:
with open(cfg['arch']['path'], 'rb') as f:
chksum.update(f.read())
if chksum.hexdigest().lower() == hashes[_fname].lower():
up2date = True
if not up2date:
os.makedirs(os.path.dirname(cfg['arch']['path']), exist_ok = True)
with open(cfg['arch']['path'], 'wb') as f, urlopen(iso) as u:
f.write(u.read())