如何在没有客户端首先请求 python 和 flask 的情况下通过 socket-io 发送数据

Question

My goal is for my Flask server to send the client data either every three seconds, or when a function is called.我的目标是让我的 Flask 服务器每三秒发送一次客户端数据，或者在调用 function 时发送客户端数据。 To do this I am using SocketIO.为此，我正在使用 SocketIO。 However based on some example code I am working with, it seems that I can only send data after a client requests something.但是，根据我正在使用的一些示例代码，我似乎只能在客户端请求某些内容后发送数据。 I don't want the client to have to 'poll' to find if there is new data, so I want the server to push it when it is ready.我不希望客户端必须“轮询”来查找是否有新数据，所以我希望服务器在准备好时推送它。

Here is what I tried so far.这是我到目前为止所尝试的。 (some of the code is unnecessary since it is based off an example) This should use socketio to push the time to the client every few seconds. （有些代码是不必要的，因为它基于一个示例）这应该使用 socketio 每隔几秒将时间推送到客户端。

HTML HTML

<!DOCTYPE HTML>
<html>
<head>
    <title>Socket-Test</title>
    <script src="//code.jquery.com/jquery-1.12.4.min.js"></script>
    <script src="//cdnjs.cloudflare.com/ajax/libs/socket.io/2.2.0/socket.io.js"></script>
    <script type="text/javascript" charset="utf-8">
        $(document).ready(function() {

            namespace = '/test';
            var socket = io(namespace);

           

            socket.on('my_response', function(msg, cb) {
                $('#log').text( $('<div/>').text(msg.data).html());
                if (cb)
                    cb();
            });
            
            
            
        });
    </script>
</head>
<body style="background-color:white;">

    <h1 style="background-color:white;">Socket</h1>
    <div id="time" ></div>
</body>
</html>

Python Python

import threading
from flask import Flask, render_template, session, copy_current_request_context,request
from flask_socketio import SocketIO, emit, disconnect
from threading import Lock
import time

async_mode = None
app = Flask(__name__)
app.config['SECRET_KEY'] = 'secret!'
socket_ = SocketIO(app, async_mode=async_mode)
thread = None
thread_lock = Lock()
clients = []
def update():
    time.sleep(1)
    emit('my_response',
         {'data': time.time},
         room=clients[0])
t=threading.Thread(target=update)



@socket_.on('connect')
def handle_connect():
    print('Client connected')
    clients.append(request.sid)
    t.start()


@app.route('/')
def index():
    
    return render_template('index.html', async_mode=socket_.async_mode)


@socket_.on('my_event', namespace='/test')
def test_message(message):
    session['receive_count'] = session.get('receive_count', 0) + 1
    emit('my_response',
         {'data': message['data'], 'count': session['receive_count']})


@socket_.on('my_broadcast_event', namespace='/test')
def test_broadcast_message(message):
    session['receive_count'] = session.get('receive_count', 0) + 1
    emit('my_response',
         {'data': time.time},
         broadcast=True)






socket_.run(app,port=8050)

I try to run it but it gives me the error RuntimeError: Working outside of request context.我尝试运行它，但它给了我错误RuntimeError: Working outside of request context.

Answer 1

I fixed my code by following this tutorial: https://www.shanelynn.ie/asynchronous-updates-to-a-webpage-with-flask-and-socket-io/我按照本教程修复了我的代码： https://www.shanelynn.ie/asynchronous-updates-to-a-webpage-with-flask-and-socket-io/

import threading
from flask import Flask, render_template, session, copy_current_request_context,request
from flask_socketio import SocketIO, emit, disconnect
from threading import Lock
import time

async_mode = None
app = Flask(__name__)
app.config['SECRET_KEY'] = 'secret!'
socket_ = SocketIO(app, async_mode=async_mode)
thread = None
thread_lock = Lock()

def update():
    
    time.sleep(1)
    socket_.emit('my_response',
         {'data': time.time()},
        namespace='/test')
    print("emitted")
    update()
t=threading.Thread(target=update)



@socket_.on('connect', namespace='/test')
def handle_connect():
    print('Client connected')
   
    if not t.isAlive():
        t.start()


@app.route('/')
def index():
    
    return render_template('index.html', async_mode=socket_.async_mode)


socket_.run(app,port=8070)

HTML HTML

<!DOCTYPE HTML>
<html>
<head>
    <title>Socket-Test</title>
    <script src="//code.jquery.com/jquery-1.12.4.min.js"></script>
    <script src="//cdnjs.cloudflare.com/ajax/libs/socket.io/2.2.0/socket.io.js"></script>
    <script type="text/javascript" charset="utf-8">
        $(document).ready(function() {

            namespace = '/test';
            var socket = io(namespace);

           console.log(("test"));

            socket.on('my_response', function(msg) {
                $('#time').text( $('<div/>').text(msg.data).html());
                
                console.log(msg);
            });
            
            
            
        });
    </script>
</head>
<body style="background-color:white;">

    <h1 style="background-color:white;">Socket</h1>
    <div id="time" ></div>
</body>
</html>

如何在没有客户端首先请求 python 和 flask 的情况下通过 socket-io 发送数据

问题描述

1 个解决方案

解决方案1
0 2022-01-02 03:53:46

如何在没有客户端首先请求 python 和 flask 的情况下通过 socket-io 发送数据

问题描述

1 个解决方案

解决方案1 0 2022-01-02 03:53:46

解决方案1
0 2022-01-02 03:53:46