如何修复Flask-uwsgi-Nginx设置中的Post请求延迟的websocket消息?

时间:2019-06-19 07:38:52

标签: python flask websocket uwsgi

我正在开发一个Flask应用程序,该应用程序具有一个由Flask的render_template函数呈现的网页。该网页包含一个表单,用于通过发布请求+ WebSocket连接提交数据以显示任务状态。提交表单后,将触发对长期运行任务的后期请求。在执行此长时间运行的任务期间,很少有WebSocket消息从烧瓶后端发送到此网页作为任务状态。但是,即使这些消息是按照正确的顺序从后端发送的,它们也仅在长时间运行的任务完成时(即,当网页接收到表单发布请求的响应时)才在网页中接收到。据我了解,WebSocket是异步的。那为什么会这样呢?

我在做什么:

发布请求处理程序-> websocket消息1-> websocket消息2->芹菜->发送请求的响应

我尝试在app.ini中添加进程,线程等。

uwsgi的app.ini

[uwsgi]
module = wsgi:app
master = true
http-socket = 127.0.0.1:7001
gevent = 10
http-websockets = true

nginx配置

server {
    listen 7000;
    server_name _;  

    location / {
        include proxy_params;
    proxy_pass http://127.0.0.1:7001;
    uwsgi_buffering off;
    }

    location /socket.io {
    include proxy_params;
        proxy_http_version 1.1;
    uwsgi_buffering off;
        proxy_buffering off;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
        proxy_pass http://127.0.0.1:7001/socket.io;

    }
}

网页websocket代码

<script type="text/javascript" charset="utf-8">
        var socket = io.connect('http://' + document.domain + ':' + location.port);

         socket.on('connect', function() {
            socket.emit('get_status')
            socket.emit('get_message')
            console.log('Websocket connected!');
            });

        socket.on('response_status',function(data){
        document.getElementById("status").innerHTML = "Status : "+data.status;
        console.log("status received");
    });


        socket.on('response_last_message',function(data){
        document.getElementById("message").innerHTML = "Message : "+data.last_message;
        console.log("Message received");
    });


</script>

Python代码:

主班

socketio = SocketIO()

def create_app():
    app = Flask(__name__)
    api = Api(app)
    socketio.init_app(app)


    with open('config.json', 'r') as conf:
        configObject = json.load(conf)

    commonConfig = commons.Common(configObject)
    socketWork = commons.SocketWork(socketio, commonConfig)


    api.add_resource(routes.IndexPage,'/', resource_class_kwargs={ 'commonConfig': commonConfig, 'socketWork': socketWork})
    api.add_resource(routes.UploadFile, '/uploadFile', resource_class_kwargs={ 'commonConfig': commonConfig, 'socketWork': socketWork})


    return app

套接字类

class SocketWork():

    def __init__(self, socketio = None, commonObj=None):
        self.commonObj = commonObj
        self.socketio = socketio
        self.socketio.on_event('get_status',self.send_last_status)
        self.socketio.on_event('get_message',self.send_last_message)

    def send_last_status(self):
        print("Send status now")
        status = self.commonObj.status
        self.socketio.emit("response_status", {"status": status})

    def send_last_message(self):
        print("Send last message")
        msg = self.commonObj.msg
        self.socketio.emit("response_last_message", {"last_message": msg})

    def send_message(self,msg):
        self.commonObj.msg = msg
        self.send_last_message()

    def send_status(self,statusVal):
        self.commonObj.status = statusVal
        self.send_last_status()

长时间运行帖子方法:

class UploadFile(Resource):

    def __init__(self, **kwargs):
        self.commonConfig = kwargs['commonConfig']
        self.socketWork    = kwargs['socketWork']

    @use_args(args.argsUploadData)
    def post(self, args):
        msg = "This is socket message"
        socketWork.send_message(msg)
        socketWork.send_status(commonConfig.config['Status']['READY'])
        sleep(15)       ###long running task
        return constants.generic_msg.PROCESSING_QUERY.name

网页中预期的WebSocket可以立即从Flask后端接收消息,但在后请求完成后接收消息。没有错误消息生成。

1 个答案:

答案 0 :(得分:0)

仔细阅读许多文章后,我知道该错误是由于 NOT 猴子修补了我的程序引起的。我应该对Gevent本身的文档有更好的了解。如果某些人遇到相同的问题,此链接将有所帮助:GeventDoc

此外,请记住,猴子补丁应该是代码中的第一件事。 在进行其他任何导入之前。