python中websocket需要我们自己实现握手代码,流程是这样:服务端启动websocket服务,并监听。当客户端连接过来时,(需要我们自己实现)服务端就接收客户端的请求数据,拿到请求头,根据请求头信息封装响应头,并将响应头发给前端,这样就完成了一次握手,接下来服务端和客户端才可以通信。
上代码,我的代码只涉及到服务端发消息给客户端的情况
先说一下代码涉及到的知识
1、单例模式
2、多线程
3、redis
4、websokcet
5、在docker容器中运行
#
!/usr/bin python
#
-*- coding:UTF-8 -*-
import
redis
import
time, threading, sched, json, socket, base64, hashlib,logging,traceback
allkv_json = ""# 发送给前端的数据
conn_list = [] # 处于在线的socket链接# 单例def singleton(cls):
instances = {}
def getinstatce(*args, **kwargs):
if cls notin instances:
instances[cls] = cls(*args, **kwargs)
return instances[cls]
return getinstatce
@singleton
class RedisUtils:
def__init__(self, port, db):
self.redis_object = redis.Redis(‘127.0.0.1‘, port, db)
self.allKV = []
def get_all_kv(self):
keys = self.redis_object.keys()
self.allKV = [key for key in keys if self.redis_object.ttl(key) isnot None]
# for key in keys:# self.allKV[key] = ‘online‘ if (time.time() - int(self.redis_object.get(key))) < 10 else ‘off_line‘class SchedTask:
allkv = []
@classmethod
def getHostOnlineStatus(cls):
global allkv_json
ru = RedisUtils(6379, 1)
ru.get_all_kv()
cls.allkv = ru.allKV
allkv_json = json.dumps(cls.allkv)
print allkv_json
@classmethod
def getHostOnlineStatusTask(cls):
threading.Thread(target=cls.getHostOnlineStatus).start()
@classmethod
def run(cls, timedelay):
while True:
s = sched.scheduler(time.time, time.sleep)
s.enter(timedelay, 1, cls.getHostOnlineStatusTask, ())
s.run()
class WebsocketUtils(threading.Thread):
MAGIC_STRING = ‘258EAFA5-E914-47DA-95CA-C5AB0DC85B11‘
HANDSHAKE_STRING = "HTTP/1.1 101 Switching Protocolsrn""Upgrade:WebSocketrn""Connection: Upgradern""Sec-WebSocket-Accept: {1}rn""WebSocket-Location: ws://{2}/chatrn""WebSocket-Protocol:chatrnrn"def__init__(self, host, port):
ifnot isinstance(host, str):
raise KeyError("The host must be a string like ‘127.0.0.1‘")
else:
self.host = host
ifnot isinstance(port, int):
raise KeyError(‘The port must be a integer‘)
else:
self.port = port
try:
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.sock.bind((host, port))
print‘=========================================================================================‘print host,port
self.sock.listen(100)
except:
print traceback.format_exc()
print‘start socket error‘
super(WebsocketUtils, self).__init__()
# 前端握手def handshake(self, conn):
headers = {}
shake = conn.recv(1024)
print shake
ifnot len(shake):
print(‘len error‘)
return False
header, data = shake.split(‘rnrn‘, 1)
for line in header.split(‘rn‘)[1:]:
key, value = line.split(‘: ‘, 1)
headers[key] = value
if‘Sec-WebSocket-Key‘notin headers:
print(‘this is not websocket, client close.‘)
print headers
conn.close()
return False
sec_key = headers[‘Sec-WebSocket-Key‘]
res_key = base64.b64encode(hashlib.sha1(sec_key + WebsocketUtils.MAGIC_STRING).digest())
str_handshke = WebsocketUtils.HANDSHAKE_STRING.replace(‘{1}‘, res_key).replace(‘{2}‘,
self.host + ":" + str(self.port))
print str_handshke
conn.send(str_handshke)
i=0
def send_msg(self):
WebsocketUtils.i+=1
global conn_list
print‘send msg‘ +str(WebsocketUtils.i)
for conn in conn_list:
try:
conn.send(‘%c%c%s‘ % (0x81, len(allkv_json), allkv_json))
except:
print‘send msg error‘
conn.close()
conn_list.remove(conn)
# 定时给前端发信息def sched_send_msg(self):
while True:
s=sched.scheduler(time.time,time.sleep)
s.enter(2,1,self.send_msg,())
s.run()
def run(self):
# 另开一个线程给各个conn发消息global conn_list
t=threading.Thread(target=self.sched_send_msg)
t.start()
while True:
print‘wait link‘try:
print self.sock
self.conn, addr = self.sock.accept()
print‘link ok‘
self.handshake(self.conn)
print‘handshake ok‘
conn_list.append(self.conn)
except:
print traceback.format_exc()
print‘error‘
time.sleep(3)
if__name__ == ‘__main__‘:
# websocket线程
websocket_utils = WebsocketUtils(‘0.0.0.0‘, 9000)
#websocket_utils.setDaemon(True) # 把当前进程设置为守护进程,主线程执行完毕,子线程均停止 websocket_utils.start()
# 定时获取主机在线信息
SchedTask.run(5)
上js代码
<html> <head> <script type="text/javascript"> var socket = new WebSocket(‘ws://192.168.81:9000‘); console.log(‘socket : ‘ + socket); socket.onopen = function(e) { console.log(‘onopen : ‘ + e); var element = document.getElementById("holder"); element.innerHTML += ‘onopen : ‘ element.innerHTML += e; element.innerHTML += "<br>"; } socket.onclose = function(e) { console.log(‘onclose : ‘ + e + ‘; length : ‘ + arguments.length); var element = document.getElementById("holder"); element.innerHTML += ‘close : ‘ element.innerHTML += e; element.innerHTML += "<br>"; } socket.onmessage = function(e) { console.log(‘onmessage : ‘ + e + ‘; length : ‘ + arguments.length); console.log(‘data : ‘ + e.data); socket.send(‘chengang‘); var element = document.getElementById("holder"); element.innerHTML += ‘onmessage : ‘ element.innerHTML += e element.innerHTML += "<br>"; element.innerHTML += ‘data : ‘ element.innerHTML += e.data; element.innerHTML += "<br>"; } </script> </head> <body> <div id="holder" style="width:600px; height:300px"></div> </body> </html>
因为是在docket容器中运行的服务端,所以需要在端口映射9000:9000 客户端js代码的ip必须是服务端宿主机的ip
可能用的命令,可能会涉及到防火墙的关闭和查看端口是否开放可以这样做
查看centos端口是否开放 在windos中 telnet 192.168.82.2 80 可以知道192.168.82.2这个主机的80端口是否开放,需要打开windows中telnet 在所有程序中打开,自行百度
查看centos端口占用 netstat -nap |grep ***
原文:https://www.cnblogs.com/lfxiao/p/9719951.html
【说明】:本文章由站长整理发布,文章内容不代表本站观点,如文中有侵权行为,请与本站客服联系(QQ:254677821)!