import logging
from collections import defaultdict
from scrapy.exceptions import NotConfigured
from scrapy.http import Response
from scrapy.http.cookies import CookieJar
from scrapy.utils.python import to_unicode
logger = logging.getLogger(__name__)
[docs]class CookiesMiddleware:
"""This middleware enables working with sites that need cookies"""
def __init__(self, debug=False):
self.jars = defaultdict(CookieJar)
self.debug = debug
@classmethod
def from_crawler(cls, crawler):
if not crawler.settings.getbool('COOKIES_ENABLED'):
raise NotConfigured
return cls(crawler.settings.getbool('COOKIES_DEBUG'))
def process_request(self, request, spider):
if request.meta.get('dont_merge_cookies', False):
return
cookiejarkey = request.meta.get("cookiejar")
jar = self.jars[cookiejarkey]
for cookie in self._get_request_cookies(jar, request):
jar.set_cookie_if_ok(cookie, request)
# set Cookie header
request.headers.pop('Cookie', None)
jar.add_cookie_header(request)
self._debug_cookie(request, spider)
def process_response(self, request, response, spider):
if request.meta.get('dont_merge_cookies', False):
return response
# extract cookies from Set-Cookie and drop invalid/expired cookies
cookiejarkey = request.meta.get("cookiejar")
jar = self.jars[cookiejarkey]
jar.extract_cookies(response, request)
self._debug_set_cookie(response, spider)
return response
def _debug_cookie(self, request, spider):
if self.debug:
cl = [to_unicode(c, errors='replace')
for c in request.headers.getlist('Cookie')]
if cl:
cookies = "\n".join("Cookie: {}\n".format(c) for c in cl)
msg = "Sending cookies to: {}\n{}".format(request, cookies)
logger.debug(msg, extra={'spider': spider})
def _debug_set_cookie(self, response, spider):
if self.debug:
cl = [to_unicode(c, errors='replace')
for c in response.headers.getlist('Set-Cookie')]
if cl:
cookies = "\n".join("Set-Cookie: {}\n".format(c) for c in cl)
msg = "Received cookies from: {}\n{}".format(response, cookies)
logger.debug(msg, extra={'spider': spider})
def _format_cookie(self, cookie, request):
"""
Given a dict consisting of cookie components, return its string representation.
Decode from bytes if necessary.
"""
decoded = {}
for key in ("name", "value", "path", "domain"):
if not cookie.get(key):
if key in ("name", "value"):
msg = "Invalid cookie found in request {}: {} ('{}' is missing)"
logger.warning(msg.format(request, cookie, key))
return
continue
if isinstance(cookie[key], str):
decoded[key] = cookie[key]
else:
try:
decoded[key] = cookie[key].decode("utf8")
except UnicodeDecodeError:
logger.warning("Non UTF-8 encoded cookie found in request %s: %s",
request, cookie)
decoded[key] = cookie[key].decode("latin1", errors="replace")
cookie_str = "{}={}".format(decoded.pop("name"), decoded.pop("value"))
for key, value in decoded.items(): # path, domain
cookie_str += "; {}={}".format(key.capitalize(), value)
return cookie_str
def _get_request_cookies(self, jar, request):
"""
Extract cookies from a Request. Values from the `Request.cookies` attribute
take precedence over values from the `Cookie` request header.
"""
def get_cookies_from_header(jar, request):
cookie_header = request.headers.get("Cookie")
if not cookie_header:
return []
cookie_gen_bytes = (s.strip() for s in cookie_header.split(b";"))
cookie_list_unicode = []
for cookie_bytes in cookie_gen_bytes:
try:
cookie_unicode = cookie_bytes.decode("utf8")
except UnicodeDecodeError:
logger.warning("Non UTF-8 encoded cookie found in request %s: %s",
request, cookie_bytes)
cookie_unicode = cookie_bytes.decode("latin1", errors="replace")
cookie_list_unicode.append(cookie_unicode)
response = Response(request.url, headers={"Set-Cookie": cookie_list_unicode})
return jar.make_cookies(response, request)
def get_cookies_from_attribute(jar, request):
if not request.cookies:
return []
elif isinstance(request.cookies, dict):
cookies = ({"name": k, "value": v} for k, v in request.cookies.items())
else:
cookies = request.cookies
formatted = filter(None, (self._format_cookie(c, request) for c in cookies))
response = Response(request.url, headers={"Set-Cookie": formatted})
return jar.make_cookies(response, request)
return get_cookies_from_header(jar, request) + get_cookies_from_attribute(jar, request)