潭州课堂25班：Ph201805201 tornado 项目 第十一课 项目改进和优化（课堂笔记）

使用  Bootstrap 前端框架

可以在 bootCDN 这里找 jquery ，poppe.js 文件

当聊天室发来一第图片链接时，自动保存图片到服务器，并保存相关信息到数据库，系统向该用户发出扑救 信息

class ChatWebsocket(tornado.websocket.WebSocketHandler, AuthBaseHandler):
    """处理 Websocket 连接"""
    walters = set()                  # 去除网络中重复的请求
    history = []                     # 存放历史信息
    history_size = 10                 # 消息列表的大小

    def open(self):
        # print('websocket opened')
        ChatWebsocket.walters.add(self)

    def on_message(self, message):
        p = tornado.escape.json_decode( message )     # 解码成为字典
        body = p['body']
        if body and ( body.startswith('http://') or body.startswith('https://') ):
            client = AsyncHTTPClient()
            save_api_url = 'http://47.107.171.155:8000/sa?save_url={}&name={}'.format( body, self.current_user )
            IOLoop.current().spawn_callback( client.fetch, save_api_url )                 # 不会等待结果
            chat = ChatWebsocket.make_chat(
                body='图片链接{}正在下载。'.format( body )
            )
            html = self.render_string('message.html', message = chat)   # 渲染 message.html 页面
            msg = {
                'html':tornado.escape.to_basestring( html ),
                'id':chat['id']
            }
            self.write_message( msg )
        else:
            chat = ChatWebsocket.make_chat(
                p['body'],
                self.current_user
            )
            html = self.render_string('message.html', message = chat)   # 渲染 message.html 页面
            msg = {
                'html':tornado.escape.to_basestring( html ),
                'id':chat['id']
            }
            ChatWebsocket.update_history( msg )
            ChatWebsocket.send_update( msg )

    @classmethod
    def make_chat(cls, body, name='系统信息', img_url='' ):
        chat = {
            'id'  : str(uuid.uuid4()),
            'body': body,
            'name': name,
            'img_url': img_url
        }
        return chat

    @classmethod
    def update_history(cls, msg):
        """更新消息列表"""
        ChatWebsocket.history.append(msg)
        if len(ChatWebsocket.history) > ChatWebsocket.history_size:
            ChatWebsocket.history = ChatWebsocket.history[ChatWebsocket.history_size:]

    @classmethod
    def send_update(cls, msg):
        """发送信息给所有用户"""
        for w in ChatWebsocket.walters:
            w.write_message(msg)

    def on_close(self):
        ChatWebsocket.walters.remove(self)

当图片保存成功后，系统要向聊天室的所有人发信息提示，

class AyncSaveHandler(AuthBaseHandler):
    """异步版本保存 URL"""
    @coroutine
    def get(self, *args, **kwargs):
        save_url = self.get_argument('save_url', None)
        name     = self.get_argument('name', '')
        client = AsyncHTTPClient()

        # res = requests.get(save_url)
        res = yield client.fetch(save_url, request_timeout=20)
        uim = UploadImg('a.jpg', self.settings['static_path'])
        uim.save_upload(res.body)
        uim.save_thumb()

        # post = add_post_for(self.current_user, uim.upload_url, uim.thumb_url)
        post = add_post_for(name, uim.upload_url, uim.thumb_url)
        chat = ChatWebsocket.make_chat(
            '用户 ' + name + '{}http://47.107.171.155:8000/post/{}'.format('上传了图片', post.id ),
            img_url=uim.thumb_url
        )
        html = self.render_string( 'message.html', message=chat )  # 渲染 message.html 页面
        msg = {
            'html': tornado.escape.to_basestring( html ),
            'id': chat['id']
        }

        ChatWebsocket.send_update( msg )