我有以下处理程序
首先，用户调用此处理程序并被重定向到 Facebook：
class LoginFacebookHandler(BasicHandler):
def get(self):
user = self.auth.get_user_by_session()
if not user:
h = hashlib.new('sha512')
h.update(str(datetime.now())+"abc")
nonce = h.hexdigest()
logging.info("hash "+str(nonce))
memcache.set(str(nonce), True, 8600)
#facebook_uri = "https://www.facebook.com/dialog/oauth?client_id=%s&redirect_uri=%s&state=%s&scope=%s" % ("20773", "http://upstrackapp.appspot.com/f", str(nonce), "email")
data = {"client_id": 20773, "redirect_uri": "http://***.appspot.com/f", "state": str(nonce), "scope": "email"}
facebook_uri = "https://www.facebook.com/dialog/oauth?%s" % (urllib.urlencode(data))
self.redirect(facebook_uri)
在他授权我的应用程序 facebook 重定向到重定向 URI（处理程序）后：
class CreateUserFacebookHandler(BasicHandler):
def get(self):
state = self.request.get('state')
code = self.request.get('code')
logging.info("state "+state)
logging.info("code "+code)
if len(code) > 3 and len(state) > 3:
cached_state = memcache.get(str(state))
logging.info("cached_state "+str(cached_state))
if cached_state:
#memcache.delete(str(state))
data = { "client_id": 20773, "redirect_uri": "http://***.appspot.com/f", "client_secret": "7f587", "code": str(code)}
graph_url = "https://graph.facebook.com/oauth/access_token?%s" % (urllib.urlencode(data))
logging.info("grph url "+graph_url)
result = urlfetch.fetch(url=graph_url, method=urlfetch.GET)
if result.status_code == 200:
fb_response = urlparse.parse_qs(result.content)
access_token = fb_response["access_token"][0]
token_expires = fb_response["expires"][0]
logging.info("access token "+str(access_token))
logging.info("token expires "+str(token_expires))
if access_token:
api_data = { "access_token": str(access_token)}
api_url = "https://graph.facebook.com/me?%s" % (urllib.urlencode(api_data))
logging.info("api url "+api_url)
api_result = urlfetch.fetch(url=api_url, method=urlfetch.GET)
if api_result.status_code == 200:
api_content = json.loads(api_result.content)
user_id = str(api_content["id"])
email = str(api_content["email"])
logging.info("user id "+str(user_id))
logging.info("email "+str(email))
h = hashlib.new('sha512')
h.update(str(user_id)+"abc")
password = h.hexdigest()
expire_data = datetime.now() + timedelta(seconds=int(token_expires))
user = self.auth.store.user_model.create_user(email, password_raw=password, access_token=access_token, token_expires=expire_data, fb_id=user_id)
else:
self.response.write.out.write("error contacting the graph api")
else:
self.response.out.write("access token not long enough")
else:
self.response.out.write("error while contacting facebook server")
else:
self.response.out.write("error no cached state")
else:
self.response.out.write("error too short")
大多数情况下，这一直有效，直到代码尝试检索 access_token 并且我最终得到“联系时出错......”。有趣的是，我记录了所有 URL、状态等，所以我进入我的日志，复制并粘贴 urlfetch 尝试打开的 URL（fb api->access_token），将其粘贴到我的浏览器中，瞧，我的 access_token + 过期了。当代码试图从图表（graph/me）中获取用户信息时，有时也会发生同样的事情。