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copied!<p>This works if anyone is interested:</p> <pre><code>from google.appengine.ext import webapp import Cookie import base64 import time import hashlib import hmac import datetime import re import calendar import email.utils import logging def _utf8(s): if isinstance(s, unicode): return s.encode("utf-8") assert isinstance(s, str) return s def _unicode(s): if isinstance(s, str): try: return s.decode("utf-8") except UnicodeDecodeError: raise HTTPError(400, "Non-utf8 argument") assert isinstance(s, unicode) return s def _time_independent_equals(a, b): if len(a) != len(b): return False result = 0 for x, y in zip(a, b): result |= ord(x) ^ ord(y) return result == 0 class ExtendedRequestHandler(webapp.RequestHandler): """Extends the Google App Engine webapp.RequestHandler.""" def clear_cookie(self,name,path="/",domain=None): """Deletes the cookie with the given name.""" expires = datetime.datetime.utcnow() - datetime.timedelta(days=365) self.set_cookie(name,value="",path=path,expires=expires, domain=domain) def clear_all_cookies(self): """Deletes all the cookies the user sent with this request.""" for name in self.cookies.iterkeys(): self.clear_cookie(name) def cookies(self): """A dictionary of Cookie.Morsel objects.""" if not hasattr(self,"_cookies"): self._cookies = Cookie.BaseCookie() if "Cookie" in self.request.headers: try: self._cookies.load(self.request.headers["Cookie"]) except: self.clear_all_cookies() return self._cookies def _cookie_signature(self,*parts): """Hashes a string based on a pass-phrase.""" hash = hmac.new("MySecretPhrase",digestmod=hashlib.sha1) for part in parts:hash.update(part) return hash.hexdigest() def get_cookie(self,name,default=None): """Gets the value of the cookie with the given name,else default.""" if name in self.request.cookies: return self.request.cookies[name] return default def set_cookie(self,name,value,domain=None,expires=None,path="/",expires_days=None): """Sets the given cookie name/value with the given options.""" name = _utf8(name) value = _utf8(value) if re.search(r"[\x00-\x20]",name + value): # Don't let us accidentally inject bad stuff raise ValueError("Invalid cookie %r:%r" % (name,value)) new_cookie = Cookie.BaseCookie() new_cookie[name] = value if domain: new_cookie[name]["domain"] = domain if expires_days is not None and not expires: expires = datetime.datetime.utcnow() + datetime.timedelta(days=expires_days) if expires: timestamp = calendar.timegm(expires.utctimetuple()) new_cookie[name]["expires"] = email.utils.formatdate(timestamp,localtime=False,usegmt=True) if path: new_cookie[name]["path"] = path for morsel in new_cookie.values(): self.response.headers.add_header('Set-Cookie',morsel.OutputString(None)) def set_secure_cookie(self,name,value,expires_days=30,**kwargs): """Signs and timestamps a cookie so it cannot be forged""" timestamp = str(int(time.time())) value = base64.b64encode(value) signature = self._cookie_signature(name,value,timestamp) value = "|".join([value,timestamp,signature]) self.set_cookie(name,value,expires_days=expires_days,**kwargs) def get_secure_cookie(self,name,include_name=True,value=None): """Returns the given signed cookie if it validates,or None""" if value is None:value = self.get_cookie(name) if not value:return None parts = value.split("|") if len(parts) != 3:return None if include_name: signature = self._cookie_signature(name,parts[0],parts[1]) else: signature = self._cookie_signature(parts[0],parts[1]) if not _time_independent_equals(parts[2],signature): logging.warning("Invalid cookie signature %r",value) return None timestamp = int(parts[1]) if timestamp < time.time() - 31 * 86400: logging.warning("Expired cookie %r",value) return None try: return base64.b64decode(parts[0]) except: return None </code></pre> <p>It can be used like this:</p> <pre><code>class MyHandler(ExtendedRequestHandler): def get(self): self.set_cookie(name="MyCookie",value="NewValue",expires_days=10) self.set_secure_cookie(name="MySecureCookie",value="SecureValue",expires_days=10) value1 = self.get_cookie('MyCookie') value2 = self.get_secure_cookie('MySecureCookie') </code></pre>

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