whoogle-search/app/filter.py
Ben Busby f4a087303d
Improve static typing throughout repo
Eventually this should be part of a separate mypy ci build, but right
now it's just a general guideline. Future commits and PRs should be
validated for static typing wherever possible.

For reference, the testing commands used for this commit were:

mypy --ignore-missing-imports --pretty --disallow-untyped-calls app/
mypy --ignore-missing-imports --pretty --disallow-untyped-calls test/
2021-03-24 15:13:52 -04:00

260 lines
8.9 KiB
Python

from app.request import VALID_PARAMS
from app.utils.results import *
from bs4 import BeautifulSoup
from bs4.element import ResultSet, Tag
from cryptography.fernet import Fernet
import re
import urllib.parse as urlparse
from urllib.parse import parse_qs
class Filter:
def __init__(self, user_keys: dict, mobile=False, config=None) -> None:
if config is None:
config = {}
self.near = config['near'] if 'near' in config else ''
self.dark = config['dark'] if 'dark' in config else False
self.nojs = config['nojs'] if 'nojs' in config else False
self.new_tab = config['new_tab'] if 'new_tab' in config else False
self.alt_redirect = config['alts'] if 'alts' in config else False
self.mobile = mobile
self.user_keys = user_keys
self.main_divs = ResultSet('')
self._elements = 0
def __getitem__(self, name):
return getattr(self, name)
@property
def elements(self):
return self._elements
def reskin(self, page: str) -> str:
# Aesthetic only re-skinning
if self.dark:
page = page.replace(
'fff', '000').replace(
'202124', 'ddd').replace(
'1967D2', '3b85ea')
return page
def encrypt_path(self, path, is_element=False) -> str:
# Encrypts path to avoid plaintext results in logs
if is_element:
# Element paths are encrypted separately from text, to allow key
# regeneration once all items have been served to the user
enc_path = Fernet(
self.user_keys['element_key']
).encrypt(path.encode()).decode()
self._elements += 1
return enc_path
return Fernet(
self.user_keys['text_key']
).encrypt(path.encode()).decode()
def clean(self, soup) -> BeautifulSoup:
self.main_divs = soup.find('div', {'id': 'main'})
self.remove_ads()
self.fix_question_section()
self.update_styling(soup)
for img in [_ for _ in soup.find_all('img') if 'src' in _.attrs]:
self.update_element_src(img, 'image/png')
for audio in [_ for _ in soup.find_all('audio') if 'src' in _.attrs]:
self.update_element_src(audio, 'audio/mpeg')
for link in soup.find_all('a', href=True):
self.update_link(link)
input_form = soup.find('form')
if input_form is not None:
input_form['method'] = 'POST'
# Ensure no extra scripts passed through
for script in soup('script'):
script.decompose()
# Update default footer and header
footer = soup.find('footer')
if footer:
# Remove divs that have multiple links beyond just page navigation
[_.decompose() for _ in footer.find_all('div', recursive=False)
if len(_.find_all('a', href=True)) > 3]
header = soup.find('header')
if header:
header.decompose()
return soup
def remove_ads(self) -> None:
"""Removes ads found in the list of search result divs
Returns:
None (The soup object is modified directly)
"""
if not self.main_divs:
return
for div in [_ for _ in self.main_divs.find_all('div', recursive=True)]:
div_ads = [_ for _ in div.find_all('span', recursive=True)
if has_ad_content(_.text)]
_ = div.decompose() if len(div_ads) else None
def fix_question_section(self) -> None:
"""Collapses the "People Also Asked" section into a "details" element
These sections are typically the only sections in the results page that
are structured as <div><h2>Title</h2><div>...</div></div>, so they are
extracted by checking all result divs for h2 children.
Returns:
None (The soup object is modified directly)
"""
if not self.main_divs:
return
question_divs = [_ for _ in self.main_divs.find_all(
'div', recursive=False
) if len(_.find_all('h2')) > 0]
if len(question_divs) == 0:
return
# Wrap section in details element to allow collapse/expand
details = BeautifulSoup(features='html.parser').new_tag('details')
summary = BeautifulSoup(features='html.parser').new_tag('summary')
summary.string = question_divs[0].find('h2').text
question_divs[0].find('h2').decompose()
details.append(summary)
question_divs[0].wrap(details)
for question_div in question_divs:
questions = [_ for _ in question_div.find_all(
'div', recursive=True
) if _.text.endswith('?')]
for question in questions:
question['style'] = 'padding: 10px; font-style: italic;'
def update_element_src(self, element: Tag, mime: str) -> None:
"""Encrypts the original src of an element and rewrites the element src
to use the "/element?src=" pass-through.
Returns:
None (The soup element is modified directly)
"""
src = element['src']
if src.startswith('//'):
src = 'https:' + src
if src.startswith(LOGO_URL):
# Re-brand with Whoogle logo
element['src'] = 'static/img/logo.png'
element['style'] = 'height:40px;width:162px'
return
elif src.startswith(GOOG_IMG) or GOOG_STATIC in src:
element['src'] = BLANK_B64
return
element['src'] = 'element?url=' + self.encrypt_path(
src,
is_element=True) + '&type=' + urlparse.quote(mime)
def update_styling(self, soup) -> None:
""""""
# Remove unnecessary button(s)
for button in soup.find_all('button'):
button.decompose()
# Remove svg logos
for svg in soup.find_all('svg'):
svg.decompose()
# Update logo
logo = soup.find('a', {'class': 'l'})
if logo and self.mobile:
logo['style'] = ('display:flex; justify-content:center; '
'align-items:center; color:#685e79; '
'font-size:18px; ')
# Fix search bar length on mobile
try:
search_bar = soup.find('header').find('form').find('div')
search_bar['style'] = 'width: 100%;'
except AttributeError:
pass
def update_link(self, link: Tag) -> None:
"""Update internal link paths with encrypted path, otherwise remove
unnecessary redirects and/or marketing params from the url
Args:
link: A bs4 Tag element to inspect and update
Returns:
None (the tag is updated directly)
"""
# Replace href with only the intended destination (no "utm" type tags)
href = link['href'].replace('https://www.google.com', '')
if 'advanced_search' in href or 'tbm=shop' in href:
# FIXME: The "Shopping" tab requires further filtering (see #136)
# Temporarily removing all links to that tab for now.
link.decompose()
return
elif self.new_tab:
link['target'] = '_blank'
result_link = urlparse.urlparse(href)
query_link = parse_qs(
result_link.query
)['q'][0] if '?q=' in href else ''
if query_link.startswith('/'):
# Internal google links (i.e. mail, maps, etc) should still
# be forwarded to Google
link['href'] = 'https://google.com' + query_link
elif '/search?q=' in href:
# "li:1" implies the query should be interpreted verbatim,
# which is accomplished by wrapping the query in double quotes
if 'li:1' in href:
query_link = '"' + query_link + '"'
new_search = 'search?q=' + self.encrypt_path(query_link)
query_params = parse_qs(urlparse.urlparse(href).query)
for param in VALID_PARAMS:
if param not in query_params:
continue
param_val = query_params[param][0]
new_search += '&' + param + '=' + param_val
link['href'] = new_search
elif 'url?q=' in href:
# Strip unneeded arguments
link['href'] = filter_link_args(query_link)
# Add no-js option
if self.nojs:
append_nojs(link)
else:
link['href'] = href
# Replace link location if "alts" config is enabled
if self.alt_redirect:
# Search and replace all link descriptions
# with alternative location
link['href'] = get_site_alt(link['href'])
link_desc = link.find_all(
text=re.compile('|'.join(SITE_ALTS.keys())))
if len(link_desc) == 0:
return
# Replace link destination
link_desc[0].replace_with(get_site_alt(link_desc[0]))