1.群聊
- web - socket--基於TCP/UDP
- http - 無狀態的短鏈接
- 長連接:客戶端和服務器保持永久性的鏈接,除非有一方主動斷開,
- 輪詢:客戶端和服務端不斷連接,然后斷開,請求響應;不能保證數據的實時性.
- 長輪詢:長輪詢:客戶端發起請求至server,服務端不響應,服務端一直等待,鏈接一直建立,等待http鏈接自動超時(默認15s),主動斷開鏈接
1.1 服務端
# 安裝模塊 gevent-websocket,基於websocket 長連接實現群聊
from flask import Flask, request, render_template
from geventwebsocket.handler import WebSocketHandler # 請求處理WSGI HTTP
from geventwebsocket.server import WSGIServer # 替換Flask原來的wsgi服務
from geventwebsocket.websocket import WebSocket # 語法提示
app = Flask(__name__)
socket_lsit = [] # 建立連接的用戶存在列表中
@app.route('/ws') # 不再需要methods
def my_ws():
# print(request.environ) # 輸出原始請求信息
ws_socket = request.environ.get('wsgi.websocket') # type:WebSocket #語法提示 #獲取連接
socket_lsit.append(ws_socket) # 獲取到的連接保存到列表中
print(len(socket_lsit)) # 查看連接數
while True:
msg = ws_socket.receive() # 基於長連接socket 接收用戶傳遞的數據
print(msg) # 查看數據
for usocket in socket_lsit: # 群聊遍歷所有用戶
if usocket == ws_socket: # 如果地址等於發送消息的客戶端地址,不用自己發給自己
continue
try: # 處理異常
usocket.send(msg) # 將消息發送給所有有效連接
except:
continue
@app.route('/wechat') # 客戶端訪問地址
def wechat():
return render_template('ws_we.html')
if __name__ == '__main__':
# app.run()
http_serv = WSGIServer(('0.0.0.0', 9527),
app,
handler_class=WebSocketHandler #websocket替換http
)
http_serv.serve_forever()
1.2 客戶端(html文件)
- 狀態碼status:
- 1 當前連接處於可用狀態
- 3 由服務器主動發起斷開
- 0 正在建立連接或連接建立失敗
- 2 客戶端主動發起斷開
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="x-ua-compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Title</title>
</head>
<body>
<input type="text" id="content"><button onclick="send_msg()">發送消息</button>
<div id="content_list">
</div>
</body>
<script type="application/javascript">
var ws = new WebSocket("ws://192.168.12.10:9527/ws");
ws.onmessage = function (messageEvent) {
console.log(messageEvent.data);
var my_div = document.getElementById("content_list");
var ptag = document.createElement("p");
ptag.innerText = messageEvent.data;
my_div.appendChild(ptag);
};
function send_msg() {
var msg = document.getElementById("content").value;
ws.send(msg);
}
</script>
</html>
2.單聊
2.1服務端
# 基於websocket 實現群聊
import json
from flask import Flask, request, render_template
from geventwebsocket.handler import WebSocketHandler # 請求處理WSGI HTTP
from geventwebsocket.server import WSGIServer # 替換Flask原來的wsgi服務
from geventwebsocket.websocket import WebSocket # 語法提示
app = Flask(__name__)
# socket_dict = {'xiaobangzhu':'abc','shangjia':'adcd'} #
socket_dict = {} # 字段存儲登錄人員信息{用戶的唯一標識:websocket連接}
@app.route('/ws/<username>') # 不再需要methods
def my_ws(username):
# print(request.environ) # 輸出原始請求信息
ws_socket = request.environ.get('wsgi.websocket') # type:WebSocket #語法提示 #獲取連接
print(ws_socket, username)
socket_dict[username] = ws_socket # 獲取到的連接保存到列表中
print(len(socket_dict), socket_dict) # 查看連接數
while True:
msg = ws_socket.receive() # 基於長連接socket 接收用戶傳遞的數據
msg_dict = json.loads(msg) # msg_dict={receiver: receiver,sender: sender,data: msg,}
receiver = msg_dict.get('receiver') # 獲取接收者的username
receiver_socket = socket_dict.get(receiver) # 根據receiver的username獲取接收者的websocket地址
receiver_socket.send(msg) # 發送接收者的消息
@app.route('/wechat')
def wechat():
return render_template('ws_one.html') #
if __name__ == '__main__':
# app.run()
http_serv = WSGIServer(('0.0.0.0', 9527), app, handler_class=WebSocketHandler)
http_serv.serve_forever()
2.2客戶端(html文件)
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
基於JavaScript 實現Websocket客戶端
<body>
<p>你的昵稱<input type="text" id="username">
<button onclick="login()">登錄聊天室</button>
</p>
<p>給<input type="text" id="receiver">發送</p>
<input type="text" id="content">
<button onclick="send_msg()">發送消息</button>
<div id="content_list" style="width: 300px">
</div>
<script type="application/javascript">
var ws = null; //ws的路由地址
function send_msg() {
var msg = document.getElementById('content').value; //獲取要發送的消息
var receiver = document.getElementById('receiver').value; //獲取接收者的username
var sender = document.getElementById('username').value; //獲取發送者的username
var send_str = { // 封裝數據結構和要發送信息
receiver: receiver,
sender: sender,
data: msg,
};
ws.send(JSON.stringify(send_str));
// 顯示我的信息
var my_div = document.getElementById('content_list');
var ptag = document.createElement('p');
ptag.innerText = msg + " : " + '我';
ptag.style.cssText = 'text-align:right';
my_div.appendChild(ptag);
}
//接收消息
function login() {
var username = document.getElementById('username').value;
ws = new WebSocket('ws://192.168.12.10:9527/ws/' + username);
ws.onmessage = function (messageEvent) {
//ws.onmessage 當ws客戶端收到消息時執行回調函數
//ws.onopen 當ws客戶端建立完成連接時,status==1 時,執行的回調函數
//ws.onclose 當ws客戶端關閉中,或者關閉時,執行的回調函數status==2,3
//ws.onerror 當ws客戶端出現錯誤時,執行回調函數.
console.log(messageEvent.data);
var obj = JSON.parse(messageEvent.data);
var my_div = document.getElementById('content_list');
var ptag = document.createElement('p');
ptag.innerText = obj.sender + " : " + obj.data;
my_div.appendChild(ptag);
};
}
</script>
</body>
</html>
3. websocket 握手原理
import socket, base64, hashlib
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.bind(('127.0.0.1', 9527))
sock.listen(5)
# 獲取客戶端socket對象
conn, address = sock.accept()
# 獲取客戶端的【握手】信息
data = conn.recv(1024)
print(data)
"""
b'GET /ws HTTP/1.1\r\n
Host: 127.0.0.1:9527\r\n
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0\r\n
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\n
Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2\r\n
Accept-Encoding: gzip, deflate\r\n
Sec-WebSocket-Version: 13\r\n
Origin: http://localhost:63342\r\n
Sec-WebSocket-Extensions: permessage-deflate\r\n
Sec-WebSocket-Key: jocLOLLq1BQWp0aZgEWL5A==\r\n
Cookie: session=6f2bab18-2dc4-426a-8f06-de22909b967b\r\n
Connection: keep-alive, Upgrade\r\n
Pragma: no-cache\r\n
Cache-Control: no-cache\r\n
Upgrade: websocket\r\n\r\n'
"""
# magic string為：258EAFA5-E914-47DA-95CA-C5AB0DC85B11
magic_string = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
def get_headers(data):
header_dict = {}
header_str = data.decode("utf8")
for i in header_str.split("\r\n"):
if str(i).startswith("Sec-WebSocket-Key"):
header_dict["Sec-WebSocket-Key"] = i.split(":")[1].strip()
return header_dict
def get_header(data):
"""
將請求頭格式化成字典
:param data:
:return:
"""
header_dict = {}
data = str(data, encoding='utf-8')
header, body = data.split('\r\n\r\n', 1)
header_list = header.split('\r\n')
for i in range(0, len(header_list)):
if i == 0:
if len(header_list[i].split(' ')) == 3:
header_dict['method'], header_dict['url'], header_dict['protocol'] = header_list[i].split(' ')
else:
k, v = header_list[i].split(':', 1)
header_dict[k] = v.strip()
return header_dict
headers = get_headers(data) # 提取請求頭信息
# 對請求頭中的sec-websocket-key進行加密
response_tpl = "HTTP/1.1 101 Switching Protocols\r\n" \
"Upgrade:websocket\r\n" \
"Connection: Upgrade\r\n" \
"Sec-WebSocket-Accept: %s\r\n" \
"WebSocket-Location: ws://127.0.0.1:9527\r\n\r\n"
value = headers['Sec-WebSocket-Key'] + magic_string
print(value,"magic+websocketkey")
ac = base64.b64encode(hashlib.sha1(value.encode('utf-8')).digest())
print(ac,"accept")
response_str = response_tpl % (ac.decode('utf-8'))
# 響應【握手】信息
conn.send(response_str.encode("utf8"))
while True:
msg = conn.recv(8096)
print(msg)
