Suppress spurious warnings from bs4

More MarkupResemblesLocatorWarning warnings have been appearing. This
seems to be caused by parsing HTML content that contains a URL.

This new change suppresses the warning at the root level of the app
before any content has been parsed, so this error shouldn't appear
again.

Fixes #968

app/__init__.py

@@ -4,14 +4,16 @@ from app.utils.session import generate_key
 from app.utils.bangs import gen_bangs_json
 from app.utils.misc import gen_file_hash, read_config_bool
 from base64 import b64encode
+from bs4 import MarkupResemblesLocatorWarning
 from datetime import datetime, timedelta
+from dotenv import load_dotenv
 from flask import Flask
 import json
 import logging.config
 import os
 from stem import Signal
 import threading
-from dotenv import load_dotenv
+import warnings
 
 from werkzeug.middleware.proxy_fix import ProxyFix
 
@@ -174,6 +176,9 @@ app.jinja_env.globals.update(
 # Attempt to acquire tor identity, to determine if Tor config is available
 send_tor_signal(Signal.HEARTBEAT)
 
+# Suppress spurious warnings from BeautifulSoup
+warnings.simplefilter('ignore', MarkupResemblesLocatorWarning)
+
 from app import routes  # noqa
 
 # Disable logging from imported modules

app/utils/results.py

@@ -1,6 +1,6 @@
 from app.models.config import Config
 from app.models.endpoint import Endpoint
-from bs4 import BeautifulSoup, NavigableString, MarkupResemblesLocatorWarning
+from bs4 import BeautifulSoup, NavigableString
 import copy
 from flask import current_app
 import html
@@ -10,9 +10,6 @@ from urllib.parse import parse_qs
 import re
 import warnings
 
-# Suppress incorrect warnings from bs4 related to parsing HTML content
-warnings.filterwarnings('ignore', category=MarkupResemblesLocatorWarning)
-
 SKIP_ARGS = ['ref_src', 'utm']
 SKIP_PREFIX = ['//www.', '//mobile.', '//m.', 'www.', 'mobile.', 'm.']
 GOOG_STATIC = 'www.gstatic.com'