tornado源码中不支持在self.write()中直接传入list对象,源代码如下

    def write(self, chunk):

        if self._finished:

            raise RuntimeError("Cannot write() after finish()")

        if not isinstance(chunk, (bytes, unicode_type, dict)):

            message = "write() only accepts bytes, unicode, and dict objects"

            if isinstance(chunk, list):

                message += ". Lists not accepted for security reasons; see http://www.tornadoweb.org/en/stable/web.html#tornado.web.RequestHandler.write"

            raise TypeError(message)

        if isinstance(chunk, dict):

            chunk = escape.json_encode(chunk)

            self.set_header("Content-Type", "application/json; charset=UTF-8")

        chunk = utf8(chunk)

        self._write_buffer.append(chunk)

但是在某些条件下我们需要传list给前端便于前端解析,因此我们可以覆写框架中的write(不建议)或者定义我们自己的write,我自己在自己定义的基类中定义了自己的write函数,代码如下:

class BaseHandler(tornado.web.RequestHandler):

    # 这是自己定义的基类,业务类继承这个基类

    def __init__(self, *argc, **kwarg):

        super(BaseHandler, self).__init__(*argc, **kwarg)

    def get_current_user(self):

        return self.get_secure_cookie("user")

    def get(self):

        self.send_error(404)

        def mywrite(self, chunk):

        # 定义自己实现的write()方法

        if self._finished:

            raise RuntimeError("Cannot write() after finish()")

        if not isinstance(chunk, (unicode_type, list, dict)):

            message = "write() only accepts bytes, unicode, list and dict objects"

            raise TypeError(message)

        if isinstance(chunk, (list, dict)):

            chunk = json.dumps(chunk).replace("</", "<\\/")

            self.set_header("Content-Type", "application/json; charset=UTF-8")

        chunk = utf8(chunk)

        self._write_buffer.append(chunk)

    def write_error(self, status_code, **kwargs):

        if status_code == 404:

            self.render('public/404.html')

        elif status_code == 500:

            self.render('public/500.html')

        else:

            self.write('error' + str(status_code))

下面是业务类,继承了自己写的基类BaseHandler

class BaseHandler(BaseHandler):

    # 这是这里是业务类

    def get(self):

        a = [1,2,3,4,5]

        self.mywrite(a)