一.websocket简单实现

ep1.py

from geventwebsocket.handler import WebSocketHandler
from gevent.pywsgi import WSGIServer
from geventwebsocket.websocket import WebSocket # 引这个模块为了注释中显示提示用

from flask import Flask, render_template,request

app = Flask(__name__)

@app.route('/my_app')
def my_app():

    return render_template('my_app.html')

@app.route('/my_ws')
def my_ws():
    print(request.environ)
    user_socket = request.environ.get('wsgi.websocket') # type:WebSocket

    while 1:
        msg = user_socket.receive()
        print(msg)
        user_socket.send(msg)

if __name__ == '__main__':
    # app.run()

    http_server = WSGIServer(('0.0.0.0',9527),app,handler_class=WebSocketHandler)
    http_server.serve_forever()

my_app.html

<body>
我即将是Websocket
</body>
<script>
    var ws = new WebSocket("ws://127.0.0.1:9527/my_ws")

    ws.onmessage = function (MessageEvent) {
        console.log(MessageEvent.data);
    }
</script>

request.environ:

{
    'GATEWAY_INTERFACE': 'CGI/1.1',
    'SERVER_SOFTWARE': 'gevent/1.4 Python/3.6',
    'SCRIPT_NAME': '',
    'wsgi.version': (1, 0),
    'wsgi.multithread': False,
    'wsgi.multiprocess': False,
    'wsgi.run_once': False,
    'wsgi.url_scheme': 'http',
    'wsgi.errors': < _io.TextIOWrapper name = '<stderr>'
    mode = 'w'
    encoding = 'UTF-8' > ,
    'SERVER_NAME': 'DESKTOP-3B0N8T7',
    'SERVER_PORT': '9527',
    'REQUEST_METHOD': 'GET',
    'PATH_INFO': '/my_ws',
    'QUERY_STRING': '',
    'SERVER_PROTOCOL': 'HTTP/1.1',
    'REMOTE_ADDR': '127.0.0.1',
    'REMOTE_PORT': '62130',
    'HTTP_HOST': '127.0.0.1:9527',
    'HTTP_CONNECTION': 'Upgrade',
    'HTTP_PRAGMA': 'no-cache',
    'HTTP_CACHE_CONTROL': 'no-cache',
    'HTTP_UPGRADE': 'websocket',
    'HTTP_ORIGIN': 'http://127.0.0.1:9527',
    'HTTP_SEC_WEBSOCKET_VERSION': '13',
    'HTTP_USER_AGENT': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/537.36',
    'HTTP_ACCEPT_ENCODING': 'gzip, deflate, br',
    'HTTP_ACCEPT_LANGUAGE': 'zh-CN,zh;q=0.9',
    'HTTP_COOKIE': 'session=cd724228-79f3-4fee-af68-f923b5298ddf',
    'HTTP_SEC_WEBSOCKET_KEY': 'Sut5Yva++5oPh3yBO8nbXw==',
    'HTTP_SEC_WEBSOCKET_EXTENSIONS': 'permessage-deflate; client_max_window_bits',
    'wsgi.input': < gevent.pywsgi.Input object at 0x00000222A00988E8 > ,
    'wsgi.input_terminated': True,
    'wsgi.websocket_version': '13',
    'wsgi.websocket': < geventwebsocket.websocket.WebSocket object at 0x00000222A009F1E8 > ,
    'werkzeug.request': < Request 'http://127.0.0.1:9527/my_ws' [GET] >
}

二.使用websocket简单应用

1.简单实现聊天, (一对一单人聊天聊天)

import json

from geventwebsocket.handler import WebSocketHandler
from gevent.pywsgi import WSGIServer
from geventwebsocket.websocket import WebSocket
from geventwebsocket.exceptions import WebSocketError

from flask import Flask,render_template,request

app = Flask(__name__)

# user_socket_list = []
user_socket_dict = {}

@app.route("/my_app")
def my_app():
    print(request.environ)
    return render_template("my_app.html")

@app.route("/my_ws/<username>")
def my_ws(username):
    user_socket = request.environ.get("wsgi.websocket") # type:WebSocket
    user_socket_dict[username] = user_socket
    print(len(user_socket_dict),user_socket_dict)
    while 1:
        try:
            msg = user_socket.receive() # 阻塞等待消息数据
            print(msg,type(msg))
            msg_dict = json.loads(msg)
            # msg = {from_user:xxx,to_user:robert,messge:"hello"}
            to_user = msg_dict.get("to_user")
            to_user_socket = user_socket_dict.get(to_user)
            to_user_socket.send(msg)
            # user_socket_dict.get(msg.get(to_user) == "robert").send(msg)
        except WebSocketError:
            user_socket_dict.pop(username)
            return "good bye"






if __name__ == '__main__':
    # app.run()
    http_serv = WSGIServer(("0.0.0.0",9527),app,handler_class=WebSocketHandler)
    http_serv.serve_forever()

s1.py

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
你的名字:<input type="text" id="nickname">
<button onclick="open_chat()">登录聊天室</button>
<p>发送至<input type="text" id="to_user"></p>
消息<input type="text" id="message">
<button onclick="send_message()">发送</button>
<div id="chat_list">

</div>
</body>
<script type="application/javascript">
    var ws = null;

    function open_chat() {
        var nickname = document.getElementById("nickname").value;
        ws = new WebSocket("ws://192.168.14.200:9527/my_ws/" + nickname); // 这里的地址是websocket服务器的地址
        ws.onopen = function () {
            alert(nickname + "!欢迎登录对骂平台!");
        };
        ws.onmessage = function (eventMessage) {
            // document.getElementById("chat_list").innerHTML += "<p>" + eventMessage.data + "</p>";

            console.log(eventMessage.data);
            var chat = JSON.parse(eventMessage.data);
            var p = document.createElement("p");
            p.style.cssText = " 250px;text-align: left";
            p.innerText = chat.from_user + "->" + chat.message;
            document.getElementById("chat_list").appendChild(p);
        };
        ws.onclose = function () {
            //断开重连机制
            console.log("连接断开了完全懵逼了");
        };
    }

    function send_message() {
        var message = document.getElementById("message").value;
        var from_user = document.getElementById("nickname").value;
        var to_user = document.getElementById("to_user").value;
        var send_str = {
            from_user: from_user,
            to_user: to_user,
            message: message
        };
        ws.send(JSON.stringify(send_str));

        var p = document.createElement("p");
        p.style.cssText = " 250px;text-align: right";
        p.innerText = send_str.message + "<-我";
        document.getElementById("chat_list").appendChild(p);
    }

</script>
</html>

my_app.html

2. 实现多人在线聊天

from geventwebsocket.handler import WebSocketHandler
from gevent.pywsgi import WSGIServer
from geventwebsocket.websocket import WebSocket
from geventwebsocket.exceptions import WebSocketError

from flask import Flask,render_template,request

app = Flask(__name__)

user_socket_list = []

@app.route("/my_app")
def my_app():
    return render_template("my_app.html")

@app.route("/my_ws")
def my_ws():
    user_socket = request.environ.get("wsgi.websocket") # type:WebSocket
    user_socket_list.append(user_socket)
    print(len(user_socket_list),user_socket_list)
    while 1:
        try:
            msg = user_socket.receive() # 阻塞等待消息数据
        except WebSocketError:
            user_socket_list.remove(user_socket)
            return "good bye"
        for u in user_socket_list:
            if u == user_socket:
                continue
            try:
                u.send(msg)
            except :
                continue




if __name__ == '__main__':
    # app.run()
    http_serv = WSGIServer(("0.0.0.0",9527),app,handler_class=WebSocketHandler)
    http_serv.serve_forever()

ep1.py

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <input type="text" id="message"><button onclick="send_message()">发送</button>
    <div id="chat_list">

    </div>
</body>
<script type="application/javascript">
    var ws = new WebSocket("ws://192.168.14.200:9527/my_ws");
    ws.onmessage = function (eventMessage) {
        // document.getElementById("chat_list").innerHTML += "<p>" + eventMessage.data + "</p>";
        var p = document.createElement("p");
        p.innerText = eventMessage.data;
        document.getElementById("chat_list").appendChild(p);
    };

    function send_message() {
        var message = document.getElementById("message").value;
        ws.send(message);
    }

</script>
</html>

my_app.html

三.websocket握手原理, 加密, 解密

下面是我用python代码进行的简单原理实现, 上文中的websocket其实已经帮我们封装好了这些方式

1.握手原理

import socket, base64, hashlib

# 分析HTTP请求
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)
# 获取客户端socket对象
conn, address = sock.accept() # 阻塞
# 获取客户端的【握手】信息
data = conn.recv(1024)
print(data)

"""
b'GET / HTTP/1.1

Host: 127.0.0.1:9527

Connection: Upgrade

Pragma: no-cache

Cache-Control: no-cache

Upgrade: websocket

Origin: http://localhost:63342

Sec-WebSocket-Version: 13

User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/537.36

Accept-Encoding: gzip, deflate, br

Accept-Language: zh-CN,zh;q=0.9

Sec-WebSocket-Key: 176bkom1UAtHfS7MUYCwlQ==

Sec-WebSocket-Extensions: permessage-deflate; client_max_window_bits

'
"""
# 由于信息是bytes类型,所以我们要将请求头信息处理转化为字典



# 获取头的第1种方式
def get_headers(data):
    header_dict = {}
    header_str = data.decode("utf8")
    for i in header_str.split("
"):
        if str(i).startswith("Sec-WebSocket-Key"):
            header_dict["Sec-WebSocket-Key"] = i.split(":")[1].strip()

    return header_dict

# 获取头的第2种方式
def get_header(data):
    """
     将请求头格式化成字典
     :param data:
     :return:
     """
    header_dict = {}
    data = str(data, encoding='utf-8')

    header, body = data.split('

', 1)
    header_list = header.split('
')
    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)  # 提取请求头信息
# # 对请求头中的sec-websocket-key进行加密
swk = headers['Sec-WebSocket-Key']
# Websocket 中的魔法字符串 magic_string
magic_string = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
value = swk + magic_string
# 176bkom1UAtHfS7MUYCwlQ==258EAFA5-E914-47DA-95CA-C5AB0DC85B11
# ZWHsGUn8ogDGd+JYzQunlQ==258EAFA5-E914-47DA-95CA-C5AB0DC85B11


# 先SHA1后base64
ac = base64.b64encode(hashlib.sha1(value.encode('utf-8')).digest())
print(value)
print(ac)
# b'PIj4+UWLuqcpcTZcMnnu9Ik6rSQ='
# b'iZFEC+HI/NqNp5g2BoENbywWBLA='


response_tpl = "HTTP/1.1 101 Switching Protocols
" 
               "Upgrade:websocket
" 
               "Connection: Upgrade
" 
               "Sec-WebSocket-Accept: %s
" 
               "WebSocket-Location: ws://127.0.0.1:9527

"

response_str = response_tpl % (ac.decode('utf-8'))
# 响应【握手】信息
conn.send(response_str.encode("utf8"))

while True:
    msg = conn.recv(8096)
    print(msg)
    import websocket加密
    conn.send(websocket加密.res())
# # magic string为：258EAFA5-E914-47DA-95CA-C5AB0DC85B11
#

2.加密

import struct

def res():
    msg_bytes = "hello".encode("utf8")
    token = b"x81"
    length = len(msg_bytes) # 5

    if length < 126:
        token += struct.pack("B", length)
    elif length == 126:
        token += struct.pack("!BH", 126, length)
    else:
        token += struct.pack("!BQ", 127, length)

    msg = token + msg_bytes

    print(msg)
    return msg

3.解密

# b'x81x83xceHxb6x85xffzx85'

hashstr = b'x81x8cxc2Jxb3x0cxaa/xdf`xadjxc4cxb0&xd7-'
# b'x81    x8c    xc2Jxb3x0cxaa/xdf`xadjxc4cxb0&xd7-'
ssss = b'x81xfex0bpx8fFxa1xa3jxc3)F7xdbD+x14xa2x199ixdax0bFx02xccI#x03xa2x19x0efxc72F;xefG

xa9x1d/kxfd+F+xefEx1bx04xa2x,'

print(ssss[2:4])  # == 140
# 与127做 与 位运算 12

# Websocket 加密 解密 3种情况
# 校验位 : 由websocket加密字符串的第二个字节与127期开始进行与位运算
# 校验位 == 127
# 校验位 == 126
# 校验位 <= 125

# 将第二个字节也就是 x83 第9-16位 进行与127进行位运算
payload = hashstr[1] & 127
print(payload)
if payload == 127:
    extend_payload_len = hashstr[2:10]  # 15.5ZB
    mask = hashstr[10:14]
    decoded = hashstr[14:]
# 当位运算结果等于127时,则第3-10个字节为数据长度
# 第11-14字节为mask 解密所需字符串
# 则数据为第15字节至结尾

# ssss = b'x81xfex0bpx8fFxa1xa3jxc3)F7xdbD+x14xa2x199ixdax0bFx02xccI#x03xa2x19x0efxc72F;xefG

xa9x1d/kxa0x0cx07gxe9;Fx02xf7G#*\xa0+x06kxff*G,'
if payload == 126:
    extend_payload_len = hashstr[2:4]  # x0bpx8fF  65535 字节 21845个汉字
    mask = hashstr[4:8]  # xa1xa3jxc3)F7
    decoded = hashstr[8:]  # 从第九个开始全是数据
# 当位运算结果等于126时,则第3-4个字节为数据长度
# 第5-8字节为mask 解密所需字符串
# 则数据为第9字节至结尾

# hashstr = b'x81x8cxc2Jxb3x0cxaa/xdf`xadjxc4cxb0&xd7-'  12
if payload <= 125:
    extend_payload_len = None
    mask = hashstr[2:6]  # xc2Jxb3x0cxaa
    decoded = hashstr[6:]  # /xdf`xadjxc4cxb0&xd7-

# 当位运算结果小于等于125时,则这个数字12就是数据的长度
# 第3-6字节为mask 解密所需字符串
# 则数据为第7字节至结尾

str_byte = bytearray()
# mask_len = 4
# [0,1,2,3]
for i in range(len(decoded)): # 12 - 0 1 2 3 4 5 6 7 8 9 10 11
    byte = decoded[i] ^ mask[i % 4] # i=0
    str_byte.append(byte)

print(str_byte.decode("utf8"))