一、概述和项目结构
在使用flask-socketio实现单聊时,需要将会话id(sid) 与用户进行绑定,通过emit('事件','消息',to=sid) ,就可以把消息单独发送给某个用户了。
flask_websocket
|--static
|--js
|--jquery-3.7.0.min.js
|--socket.io_4.3.1.js
|--templates
|--chat
|--single.html
|--app.py
1.1、python版本
python3.9.0
1.2、依赖包
Flask==2.1.0
eventlet==0.33.3
Flask-SocketIO==5.3.4
1.3、js文件下载
https://code.jquery.com/jquery-3.7.0.min.jshttps://code.jquery.com/jquery-3.7.0.min.jshttps://cdnjs.cloudflare.com/ajax/libs/socket.io/4.3.1/socket.io.min.jshttps://cdnjs.cloudflare.com/ajax/libs/socket.io/4.3.1/socket.io.min.js
二、具体代码
2.1、具体逻辑
1、先请求http://127.0.0.1:5000/single/chat?name=lhz 与后端建立连接,将会用户名与会话id绑定关系
2、指定消息发送给哪个用户
3、展示在线的用户名字,用户退出连接时通知其他用户
2.2、app.py
from flask import Flask,render_template,request,jsonify
from flask_socketio import SocketIO,send,emit,join_room,leave_roomapp = Flask(__name__,static_folder='./static',template_folder='./templates')
socketio = SocketIO(app,cors_allowed_origins='*',async_mode ='eventlet')
from flask_socketio import ConnectionRefusedError'''
单对单聊天功能
1、用户连接时,携带上用户名,sid记录到该用户名的字典中
2、通过sid实现单聊
3、通过sid判断用户是否在线中
'''USER = {} #{'lhz':{'sid':'xxxx'}}@app.route('/single/chat')
def single():name = request.args.get('name')return render_template('chat/single.html',data={'name':name})class SingleChat(Namespace):def on_connect(self):name = request.args.get('name')sid = request.sid# 把当前用户写入到在线中if name in USER:print('有其他用户了', '直接覆盖')# raise ConnectionRefusedError('用户已经在线了')USER[name] = {'sid': sid}else:USER[name] = {'sid': sid}# send({'code':200,'msg':'使用send返回的,给connect事件'})#告诉在线用户,现在在线的用户情况online_users = [name_ for name_, dic in USER.items()]emit('connect',online_users,broadcast=True)def on_disconnect(self):sid = request.sidprint('disconnect,','sid=',sid)del_name = Falsefor name,dic in USER.items():if sid == dic.get('sid'):del_name = namebreakif del_name:USER.pop(del_name)print(USER,'当前用户消息')online_users = [name_ for name_, dic in USER.items()]emit('disconnect', {'leave':del_name,'online_users':online_users}, broadcast=True)def on_single_chat(self,data):name = data.get('name') #接收消息的用户msg = data.get('msg') #消息sendName = data.get('sendName') #发送消息的用户sid_dic = USER.get(name)if sid_dic:#给该用户发送消息emit('single_chat',{'name':sendName,'msg':msg},to=sid_dic.get('sid'))#告诉发送方,消息发送成功emit('success',{'code':200,'msg':msg,'name':name})print(name,'用户在线,可以发送')else:#告诉发送方,消息发送失败emit('success',{'code':400,'msg':'该用户不在线,无法发送消息'})print(name, '用户不在线,不可以发送')socketio.on_namespace(SingleChat('/single/chat'))if __name__ == '__main__':socketio.run(app,debug=True)
2.3、single.html
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title><script type="application/javascript" src="/static/js/jquery-3.7.0.min.js"></script><script type="application/javascript" src="/static/js/socket.io_4.3.1.js"></script><script type="application/javascript">const data = {{ data|tojson }};const name = data.name; // 当前用户名//1、发起连接const socket = io('http://'+document.domain+':'+location.port+'/single/chat',{query:{'token':'123456','name':name}});//2、监听connect事件,socket.on('connect',function (data) {console.log(data);const showDiv = $('#showDataId');if (data){//将当前用户的名字删除for (let i = data.length - 1; i >= 0; i--) {if (data[i] === name) {data.splice(i, 1);}}//展示在线的用户名if(data.length>=1){const pElement = $('<p>').text('[公告]在线的用户:'+data);//添加到展示的div标签中showDiv.append(pElement);}else{const pElement = $('<p>').text('[公告] 当前只有您在线...');//添加到展示的div标签中showDiv.append(pElement);}}});// 3、监听disconnect事件,展示退出的用户消息,通知其他人socket.on('disconnect',function (dic) {const showDiv = $('#showDataId');const data = dic.online_users;const leave = dic.leave;if (data){//将当前用户的名字删除for (let i = data.length - 1; i >= 0; i--) {if (data[i] === name) {data.splice(i, 1);}}// 1、展示谁离线了const pElement = $('<p>').text('[公告] '+leave+'离线了...');//添加到展示的div标签中showDiv.append(pElement);//2、展示还在线的用户if(data.length>=1){const pElement = $('<p>').text('[公告]在线的用户:'+data);//添加到展示的div标签中showDiv.append(pElement);}else{const pElement = $('<p>').text('[公告] 当前只有您在线...');//添加到展示的div标签中showDiv.append(pElement);}}});//4、监听单聊事件,single_chatsocket.on('single_chat',function (data) {const sendName = data.name;const msg = data.msg;const showDiv = $('#showDataId');//展示别人发送的消息if(sendName===name){}else {const pElement = $('<p>').text(sendName+'>'+msg);//添加到展示的div标签中showDiv.append(pElement);}})//5、监听消息发送是否成功,失败时要展示socket.on('success',function (data) {const code = data.code;const msg = data.msg;const name = data.name;const showDiv = $('#showDataId');if (code===200){const pElement = $('<p>').text('you to('+name+') >'+msg);//添加到展示的div标签中showDiv.append(pElement);}else {alert(msg)}})//6、发送消息function sendMsg() {const recvName = $('#recvUserId').val();const msg = $('#inputDataId').val();socket.emit('single_chat',{'name':recvName,'msg':msg,'sendName':name})}</script>
</head>
<body>
<div id="showDataId"></div>
<div><p><input type="text" id="recvUserId" value="接收用户"><input type="text" id="inputDataId" value="消息"><input type="button" id="submitId" value="发送消息" onclick="sendMsg()"></p></div></body>
</html>
三、代码测试
1、开启三个浏览器标签,分别输入
http://127.0.0.1:5000/single/chat?name=lhz
http://127.0.0.1:5000/single/chat?name=zzh
http://127.0.0.1:5000/single/chat?name=yf
2、两两之间互发消息
3、关闭lhz的浏览器标签
4、关闭zzh的浏览器标签