telegram-crawler/make_tracked_links_list.py
2021-04-25 14:13:52 +02:00

249 lines
7.3 KiB
Python

import asyncio
import logging
import os
import re
from asyncio.exceptions import TimeoutError
from html import unescape
from time import time
from urllib.parse import unquote
import aiohttp
from aiohttp import ClientConnectorError
PROTOCOL = 'https://'
BASE_URL = 'telegram.org'
# its necessary to help crawler to find more links
HIDDEN_URLS = {
# 'corefork.telegram.org',
'telegram.org/privacy/gmailbot',
'telegram.org/tos',
'telegram.org/tour',
'telegram.org/evolution',
'desktop.telegram.org/changelog',
}
BASE_URL_REGEX = r'telegram.org'
# disable crawling sub links for specific domains and url patterns
CRAWL_RULES = {
# every rule is regex
# empty string means match any url
# allow rules with higher priority than deny
'translations.telegram.org': {
'allow': {
r'^[^/]*$', # root
r'org/[^/]*/$', # 1 lvl sub
r'/en/[a-z_]+/$' # 1 lvl after /en/
},
'deny': {
'', # all
}
},
'bugs.telegram.org': { # crawl first page of cards sorted by rating
'deny': {
# r'/c/[0-9]+/[0-9]+', # disable comments
'',
},
},
'instantview.telegram.org': {
'allow': {
'contest/winners'
},
'deny': {
'file/',
r'templates/.+',
'samples/',
'contest/',
},
},
'core.telegram.org': {
'deny': {
'file/',
'tdlib/docs/classtd',
'constructor/',
'method/',
'type/',
},
},
'telegram.org': {
'deny': {
'file/',
r'apps$'
},
}
}
DIRECT_LINK_REGEX = r'([-a-zA-Z0-9@:%._\+~#]{0,249}' + BASE_URL_REGEX + r')'
ABSOLUTE_LINK_REGEX = r'([-a-zA-Z0-9@:%._\+~#]{0,248}' + BASE_URL_REGEX + r'\b[-a-zA-Z0-9@:%_\+.~#?&//=]*)'
RELATIVE_LINK_REGEX = r'\/(?!\/)([-a-zA-Z0-9\/@:%._\+~#]{0,249})'
DOM_ATTRS = ['href', 'src']
OUTPUT_FILENAME = os.environ.get('OUTPUT_FILENAME', 'tracked_links.txt')
# unsecure but so simple
CONNECTOR = aiohttp.TCPConnector(ssl=False)
TIMEOUT = aiohttp.ClientTimeout(total=30)
logging.basicConfig(format='%(message)s', level=logging.DEBUG)
logger = logging.getLogger(__name__)
VISITED_LINKS = set()
LINKS_TO_TRACK = set()
def should_exclude(url: str) -> bool:
direct_link = re.findall(DIRECT_LINK_REGEX, url)[0]
domain_rules = CRAWL_RULES.get(direct_link)
if not domain_rules:
return False
allow_rules = domain_rules.get('allow', set())
deny_rules = domain_rules.get('deny', set())
exclude = False
for regex in deny_rules:
if re.search(regex, url):
exclude = True
break
for regex in allow_rules:
if re.search(regex, url):
exclude = False
break
return exclude
def find_absolute_links(html: str) -> set[str]:
absolute_links = set(re.findall(ABSOLUTE_LINK_REGEX, html))
return {link for link in absolute_links if not should_exclude(link)}
def find_relative_links(html: str, cur_link: str) -> set[str]:
direct_cur_link = re.findall(DIRECT_LINK_REGEX, cur_link)[0]
# optimization. when we want to exclude domain
if should_exclude(cur_link):
return set()
relative_links = set()
for attr in DOM_ATTRS:
regex = f'{attr}="{RELATIVE_LINK_REGEX}'
links = re.findall(regex, html)
for link in links:
url = f'{direct_cur_link}/{link}'
if not should_exclude(url):
relative_links.add(url)
return relative_links
def cleanup_links(links: set[str]) -> set[str]:
cleaned_links = set()
for tmp_link in links:
# normalize link
link = unquote(tmp_link)
link = unescape(link)
link = link.replace('www.', '')
link = link.replace('http://', '').replace('https://', '')
# skip anchor links
if '#' in link:
continue
# remove get params from link
if '?' in link:
link = ''.join(link.split('?')[:-1])
# skip mailto:
link_parts = link.split('.')
if '@' in link_parts[0]:
continue
cleaned_links.add(link)
return cleaned_links
async def crawl(url: str, session: aiohttp.ClientSession):
if url in VISITED_LINKS:
return
VISITED_LINKS.add(url)
try:
logger.info(f'[{len(VISITED_LINKS)}] Process {url}')
async with session.get(f'{PROTOCOL}{url}', allow_redirects=False, timeout=TIMEOUT) as response:
status_code = response.status
content_type = response.headers.get('content-type')
if status_code != 200:
return
if 'text/html' in content_type:
LINKS_TO_TRACK.add(url)
html = await response.text()
absolute_links = cleanup_links(find_absolute_links(html))
relative_links = cleanup_links(find_relative_links(html, url))
sub_links = absolute_links | relative_links
await asyncio.gather(*[crawl(url, session) for url in sub_links])
elif 'application/javascript' in content_type:
LINKS_TO_TRACK.add(url)
elif 'text/css' in content_type:
LINKS_TO_TRACK.add(url)
elif 'application/json' in content_type:
LINKS_TO_TRACK.add(url)
else:
# TODO track hashes of image/svg/video content types
logger.info(f'Unhandled type: {content_type}')
# telegram url can work with and without trailing slash (no redirect). P.S. not on every sub domain ;d
# so this is a problem when we have random behavior with link will be added
# this if resolve this issue. If available both link we prefer without trailing slash
without_trailing_slash = url[:-1:] if url.endswith('/') else url
if without_trailing_slash in LINKS_TO_TRACK and \
f'{without_trailing_slash}/' in LINKS_TO_TRACK:
LINKS_TO_TRACK.remove(f'{without_trailing_slash}/')
except UnicodeDecodeError:
logger.warning('Codec can\'t decode byte. So its was a tgs file')
except ClientConnectorError:
logger.warning(f'Wrong link: {url}')
except TimeoutError:
logger.warning(f'Retrying {url}')
VISITED_LINKS.remove(url)
await asyncio.gather(crawl(url, session))
async def start(url_list: set[str]):
async with aiohttp.ClientSession(connector=CONNECTOR) as session:
await asyncio.gather(*[crawl(url, session) for url in url_list])
if __name__ == '__main__':
HIDDEN_URLS.add(BASE_URL)
logger.info('Start crawling links...')
start_time = time()
asyncio.get_event_loop().run_until_complete(start(HIDDEN_URLS))
logger.info(f'Stop crawling links. {time() - start_time} sec.')
try:
with open(OUTPUT_FILENAME, 'r') as f:
OLD_URL_LIST = set([l.replace('\n', '') for l in f.readlines()])
logger.info(f'Is equal: {OLD_URL_LIST == LINKS_TO_TRACK}')
logger.info(f'Deleted: {OLD_URL_LIST - LINKS_TO_TRACK}')
logger.info(f'Added: {LINKS_TO_TRACK - OLD_URL_LIST}')
except IOError:
pass
with open(OUTPUT_FILENAME, 'w') as f:
f.write('\n'.join(sorted(LINKS_TO_TRACK)))