Python HTTP 599:连接已关闭（Tornado）

Question

我得到这个错误：

HTTP 599: Connection closed [E 130405 11:43:14 web:1031] Uncaught exception GET /networks/1/sensors/1/alarm (127.0.0.1)

执行以下代码时：

from tornado.stack_context import ExceptionStackContext

def handle_exc(*args):
print('Exception occured')
return True

@tornado.gen.engine
def check_status_changes(netid, sensid):

    como_url = "".join(['http://131.114.52:44444/ztc?netid=', str(netid), '&sensid=', str(sensid), '&start=-5s&end=-1s'])

    http_client = AsyncHTTPClient()
    response = yield tornado.gen.Task(http_client.fetch, como_url)

    if response.error is not None:
            print("Terzo")
            print response.error
            with ExceptionStackContext(handle_exc):
                response.rethrow()
    else:
        print('Handle request')

    for line in response.body.split("\n"):
                if line != "": 
                    #net = int(line.split(" ")[1])
                    #sens = int(line.split(" ")[2])
                    #stype = int(line.split(" ")[3])
                    value = int(line.split(" ")[4])
                    print value
                    yield value
                    return


class AlarmHandler(BaseHandler):
    @tornado.web.authenticated
    @tornado.web.asynchronous
    @tornado.gen.engine
    def get(self, netid, sensid):
        self.lock_tables("read", ['devices'])
        status = self.db.get("SELECT status from devices \
                          WHERE id=%s AND network_id=%s", sensid, netid)
        print("Primo")
        print status

        try:
            periodic = tornado.ioloop.PeriodicCallback(check_status_changes(netid, sensid), 5000)
            value = periodic.start()
            print("Secondo")
            print value
        except:
            print("Quarto")
            periodic.stop()
            self.finish()
            return
        if value != status['status']:

            self.lock_tables("write", ['devices'])
            self.db.execute("UPDATE devices SET status=%s \
                             WHERE id=%s AND network_id=%s", value, netid, sensid)
            self.unlock_tables()
            self.notice("Status changed")

在类AlarmHandler中有一个称为check_status_changes的周期例程。在这个函数中，当有response.error时，我获得标题的错误。

如何设置if错误条件以返回类并管理该情况？谢谢您。

其他信息

如果我做一个龙卷风的屏幕，我看到这个：

Primo

{'status': None}

Secondo

None

Terzo

HTTP 599: Connection closed

Exception occured

所以，我认为程序在返回异常之前关闭连接！

在html控制台中，我看到这个错误：

File "./wsn.py", line 226, in check_status_changes for line in response.body.split("\n"): AttributeError: 'NoneType' object has no attribute 'split'

Answer 1

你提出了一个例外：

if response.error:
        print("Terzo")
        print response.error
        raise Exception(response.error)
        return

这将是一个Uncaught Exception。您应该编写此代码来处理异常而不引发异常。E、 记录错误信息并中止数据库更新。