class BaseHandler(CommonRequestHandler):
"""Base RequestHandler for this application.
All the RequestHandler classes in this application should be a
child of this class.
"""
# Whether the login cookie duration has to be refreshed when
# this handler is called. Useful to filter asynchronous
# requests.
refresh_cookie = True
@catch_exceptions
def prepare(self):
"""This method is executed at the beginning of each request.
"""
self.set_header("Cache-Control", "no-cache, must-revalidate")
self.sql_session = Session()
self.contest = Contest.get_from_id(self.application.service.contest, self.sql_session)
localization_dir = os.path.join(os.path.dirname(__file__), "mo")
if os.path.exists(localization_dir):
tornado.locale.load_gettext_translations(localization_dir, "cms")
self._ = self.get_browser_locale().translate
self.r_params = self.render_params()
def get_current_user(self):
"""Gets the current user logged in from the cookies
If a valid cookie is retrieved, return a User object with the
username specified in the cookie. Otherwise, return None.
"""
timestamp = time.time()
if self.get_secure_cookie("login") is None:
return None
try:
cookie = pickle.loads(self.get_secure_cookie("login"))
username = str(cookie[0])
last_update = int(cookie[1])
except:
self.clear_cookie("login")
return None
# Check if the cookie is expired.
if timestamp - last_update > config.cookie_duration:
self.clear_cookie("login")
return None
user = self.sql_session.query(User).filter_by(contest=self.contest).filter_by(username=username).first()
if user is None:
self.clear_cookie("login")
return None
if self.refresh_cookie:
self.set_secure_cookie("login", pickle.dumps((user.username, int(time.time()))), expires_days=None)
# If this is the first time we see user during the active
# phase of the contest, we note that his/her time starts from
# now.
if self.contest.phase(timestamp) == 0 and user.starting_time is None:
logger.info("Starting now for user %s" % user.username)
user.starting_time = timestamp
self.sql_session.commit()
return user
def render_params(self):
"""Return the default render params used by almost all handlers.
return (dict): default render params
"""
ret = {}
ret["timestamp"] = int(time.time())
ret["contest"] = self.contest
ret["url_root"] = get_url_root(self.request.path)
ret["valid_phase_end"] = self.contest.stop
if self.contest is not None:
ret["phase"] = self.contest.phase(ret["timestamp"])
# If we have a user logged in, the contest may be ended
# before contest.stop if the user has finished the time
# allocated for him/her.
if ret["phase"] == 0 and self.current_user is not None and self.contest.per_user_time is not None:
delta = ret["timestamp"] - self.current_user.starting_time
if delta >= self.contest.per_user_time:
ret["phase"] = 1
user_end_time = self.current_user.starting_time + self.contest.per_user_time
if user_end_time < self.contest.stop:
ret["valid_phase_end"] = user_end_time
ret["contest_list"] = self.sql_session.query(Contest).all()
ret["cookie"] = str(self.cookies)
return ret
def finish(self, *args, **kwds):
""" Finishes this response, ending the HTTP request.
We override this method in order to properly close the database.
"""
if hasattr(self, "sql_session"):
logger.debug("Closing SQL connection.")
try:
self.sql_session.close()
except Exception as error:
logger.warning("Couldn't close SQL connection: %r" % error)
tornado.web.RequestHandler.finish(self, *args, **kwds)
class BaseHandler(CommonRequestHandler):
"""Base RequestHandler for this application.
All the RequestHandler classes in this application should be a
child of this class.
"""
def safe_get_item(self, cls, ident, session=None):
"""Get item from database of class cls and id ident, using
session if given, or self.sql_session if not given. If id is
not found, raise a 404.
cls (class): class of object to retrieve.
ident (string): id of object.
session (session/None): session to use.
return (object/404): the object with the given id, or 404.
"""
if session is None:
session = self.sql_session
entity = cls.get_from_id(ident, session)
if entity is None:
raise tornado.web.HTTPError(404)
return entity
def prepare(self):
"""This method is executed at the beginning of each request.
"""
# Attempt to update the contest and all its references
# If this fails, the request terminates.
self.set_header("Cache-Control", "no-cache, must-revalidate")
self.sql_session = Session()
self.sql_session.expire_all()
self.contest = None
localization_dir = os.path.join(os.path.dirname(__file__), "mo")
if os.path.exists(localization_dir):
tornado.locale.load_gettext_translations(localization_dir, "cms")
def render_params(self):
"""Return the default render params used by almost all handlers.
return (dict): default render params
"""
params = {}
params["timestamp"] = int(time.time())
params["contest"] = self.contest
params["url_root"] = get_url_root(self.request.path)
if self.contest is not None:
params["phase"] = self.contest.phase(params["timestamp"])
# Keep "== None" in filter arguments
params["unanswered"] = self.sql_session.query(Question)\
.join(User)\
.filter(User.contest_id == self.contest.id)\
.filter(Question.reply_timestamp == None)\
.filter(Question.ignored == False)\
.count()
params["contest_list"] = self.sql_session.query(Contest).all()
params["cookie"] = str(self.cookies)
return params
def finish(self, *args, **kwds):
""" Finish this response, ending the HTTP request.
We override this method in order to properly close the database.
"""
logger.debug("Closing SQL connection.")
self.sql_session.close()
tornado.web.RequestHandler.finish(self, *args, **kwds)
def get_non_negative_int(self, argument_name, default, allow_empty=True):
""" Get a non-negative integer from the arguments.
Use default if the argument is missing; If allow_empty=False,
Empty values such as "" and None are not permitted.
Raise ValueError if the argument can't be converted into a
non-negative integer.
"""
argument = self.get_argument(argument_name, repr(default))
if allow_empty and \
(argument is None or argument == "" or argument == "None"):
return None
try:
argument = int(argument)
except:
raise ValueError("%s: can't cast %s to int." %
(argument_name, argument))
if argument < 0:
raise ValueError("%s is negative." % argument_name)
return argument
