flask POOL,websocket握手

一.POOL

Pool就是为了多线程访问数据库,减少数据库压力

回顾pymysql

import pymysql
#建立连接
mysql_conn = pymysql.connect(host="127.0.0.1",
                             port=3306,
                             user="root",
                             password="",
                             charset="utf8",
                             db="day115")
#创建游标
c = mysql_conn.cursor(cursor=pymysql.cursors.DictCursor)

sql = "select * from users WHERE name='jwb' and age=73 "
# 光标执行sql
# res为生成几行
res = c.execute(sql)

#获取结果
print(c.fetchall())

c.close()
mysql_conn.close()

创建POOL

import pymysql
from DBUtils.PooledDB import PooledDB
POOL = PooledDB(
    creator=pymysql,  # 使用链接数据库的模块
    maxconnections=6,  # 连接池允许的最大连接数，0和None表示不限制连接数
    mincached=2,  # 初始化时，链接池中至少创建的空闲的链接，0表示不创建
    maxcached=5,  # 链接池中最多闲置的链接，0和None不限制
    maxshared=3,  # 链接池中最多共享的链接数量，0和None表示全部共享。PS: 无用，因为pymysql和MySQLdb等模块的 threadsafety都为1，所有值无论设置为多少，_maxcached永远为0，所以永远是所有链接都共享。
    blocking=True,  # 连接池中如果没有可用连接后，是否阻塞等待。True，等待；False，不等待然后报错
    maxusage=None,  # 一个链接最多被重复使用的次数，None表示无限制
    setsession=[],  # 开始会话前执行的命令列表。如：["set datestyle to ...", "set time zone ..."]
    ping=0,
    # ping MySQL服务端，检查是否服务可用。
    #  如：0 = None = never,
    # 1 = default = whenever it is requested,
    # 2 = when a cursor is created,
    # 4 = when a query is executed,
    # 7 = always
    host="127.0.0.1",
    port=3306,
    user="root",
    password="",
    charset="utf8",
    db="day115"
)

#
# conn = POOL.connection() # pymysql - conn
# cur = conn.cursor(cursor=pymysql.cursors.DictCursor)
#
# sql = "select * from users WHERE name='jwb' and age=73 "
#
# res = cur.execute(sql)
#
#
# print(cur.fetchall())
#
# conn.close()

执行线程池

from dbpool import POOL
import pymysql

def create_conn():
    conn = POOL.connection()
    cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)

    return conn,cursor

def close_conn(conn,cursor):
    cursor.close()
    conn.close()

def insert(sql,args):
    conn,cursor = create_conn()
    res = cursor.execute(sql,args)
    conn.commit()
    close_conn(conn,cursor)
    return res

def fetch_one(sql,args):
    conn,cursor = create_conn()
    cursor.execute(sql,args)
    res = cursor.fetchone()
    close_conn(conn,cursor)
    return res

def fetch_all(sql,args):
    conn,cursor = create_conn()
    cursor.execute(sql,args)
    res = cursor.fetchall()
    close_conn(conn,cursor)
    return res

# sql = "insert into users(name,age) VALUES (%s, %s)"

# insert(sql,("mjj",9))

sql = "select * from users where name=%s and age=%s"

print(fetch_one(sql,("mjj",9)))

二.socket握手

就是在客户端请求头中获取Sec-WebSocket-Key与宝藏magic_string = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'进行匹配

当与客户端验证成功后就已经进行了握手

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)
# 获取客户端socket对象
conn, address = sock.accept()
# 获取客户端的【握手】信息
data = conn.recv(1024)
print(data)
"""
GET /ws HTTP/1.1\r\n
Host: 127.0.0.1:9527\r\n
Connection: Upgrade\r\n
Pragma: no-cache\r\n
Cache-Control: no-cache\r\n
User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36\r\n
Upgrade: websocket\r\n
Origin: http://localhost:63342\r\n
Sec-WebSocket-Version: 13\r\n
Accept-Encoding: gzip, deflate, br\r\n
Accept-Language: zh-CN,zh;q=0.9\r\n
Cookie: session=a6f96c20-c59e-4f33-84d9-c664a2f29dfc\r\n
Sec-WebSocket-Key: MAZZU5DPIxWmhk/UWL2+BA==\r\n  #这个就是那把钥匙
Sec-WebSocket-Extensions: permessage-deflate; client_max_window_bits\r\n\r\n
"""
# 以下动作是有websockethandler完成的
# magic string为：258EAFA5-E914-47DA-95CA-C5AB0DC85B11

def get_headers(data): #在获取的data列表中通过分割获取Sec-WebSocket-Key
    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

headers = get_headers(data)  # 提取请求头信息
#
magic_string = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
#Sec-WebSocket-Key: MAZZU5DPIxWmhk/UWL2+BA==
value = headers['Sec-WebSocket-Key'] + magic_string
print(value)
#将钥匙Sec-WebSocket-Key和宝藏magic_string进行加密
ac = base64.b64encode(hashlib.sha1(value.encode('utf-8')).digest())

# 对请求头中的sec-websocket-key进行加密
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"
print(ac.decode('utf-8'))
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)

需要在前端中访问

<!DOCTYPE html>
<html lang="zh-CN">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>

</body>
<script type="application/javascript">
  var ws = new WebSocket("ws://127.0.0.1:9527/ws");

</script>
</html>

发现,在前端发送的数据vm.send("abc)发到后端的数据是加密的,需要进行解密

解密方法

比如发送到服务端的是

b'\x81\x83H\xc0x\xa6y\xf2K'

第一个为统一的的\x81,用它的后一位与127求^,结果分三种 小于等于125,126,127
然后根据后面的数据长度/密码/数据/进行解密

#b'\x81\x89\xf3\x99\x81-\x15\x05\x01\xcbO\x1be\x97]'
#b'\x81\x85s\x92a\x10\x1b\xf7\r|\x1c'
#b'\x81\x83H\xc0x\xa6y\xf2K'

hashstr = b'\x81\x85s\x92a\x10\x1b\xf7\r|\x1c'
# b'\x81 \x85s \x92a\x10\x1b\xf7  \r|\x1c' <126
# \x85s = 5
hashstr = b'\x81\xfe\x02\xdc\x8d\xe8-\xb2hm\xa5W5u\xc8:\x16\x0c\x95(kt\x87W\x00b\xc52\x01\x0c\x95\x1fdi\xbeW9A\xcb\x1c\x0f\x07\x91>iS\xa7W)A\xc9\n\x06\x0c\x95;h`\xab]1d\xca)\x07\r\x9a,j~\x9fW1b\xc2\x0e\x01\x0e\x80\x16eG\xb7W\x00Y\xcb2(\r\x80*iR\x8cV4c\xca\x15\x06\x0c\x94-nh\xafU\t^\xc9\x0c\x00\r\xa0\x19iQ\xa6Z\nK\xc9\n\x00\x0e\xaa:iR\xa3W\x0bm\xc2\x0e\x01\r\x92\x12hW\xbaV4c\xc8\x11&\r\x92*eR\x86V7f\xc8\x16\x1b\x00\xad7bT\xa1U\x16~\xc5\r0\r\xa8:hP\xb0V4c\xcb\x1c\x07\x01\xac5bT\xa1T!Z\xcb8(\x0c\x949iR\xa3[\x14s\xc9\n\x06\x0c\x94-nh\xafZ"r\xc8\x1c\x11\r\x912hT\x8dW\x11K\xc8"!\x07\x91>iS\x88W\x08a\xc87\x05\r\x95/di\xbaW3_\xc2\x0e\x01\x0e\xac\x10hT\xb5W2\x7f\xc8\x11&\x0c\x949kX\xb9]1d\xc9\n\x00\r\x83.hN\xa9Z\nB\xc5=?\x00\xbb6bT\xa1W1}\xc8$6\r\x89\x03iQ\xa4]1d\xc9\t(\r\x8c,hW\x8dZ=g\xc9\x0b\x06\x00\x9a\x1diQ\xb2Q\rj\xc8\x1c&\x0c\x95\x1fhR\xb1V5E\xc2\x0e\x01\x0c\x92\x03iP\x97V5h\xc9\x0f\x1e\x07\x91>dq\xb2U0r\xc55*\r\xbd\x14bT\xa1V5e\xc8\x1c\x11\r\x910hx\xa1Q\rj\xc59(\x0e\xb1;iU\xb1W(P\xca8"\x0f\x8a#hg\xa7V5R\xc8\r-\r\xbb6eh\xa8]1d\xc8\x1c\x11\x0c\x96*kt\xa4W\x02P\xc5\x1c7\r\xa8\x04h`\xbcZ8g\xc2\x0e\x01\x0c\x96\x17kp\x80[\x14s\xc9\n\x06\r\x94\x01kp\xa3V4c\xca"\x0b\x07\x91>iP\xa0W#t\xc83\x02\x0f\x8a3bT\xa1V0W\xc84\x08\r\x89$hT\xafT>}\xc9\x0b\x12\x0b\xad0iV\xa0V5E\xce2\x0c\x0c\x93?dk\xa3[\x0eE\xcb&5\x0c\x949nh\xacZ9Q\xca\x17\x03\x0b\xad3ey\x8eW\x08i\xca\x1f\x04\x07\x91>kE\x89U\x17n\xc5;"\r\x83,bT\xa1W2\x7f\xc5+\x1c\r\x92\x12jR\x82]1d\xcb*"\x0c\x96\x17hm\xa5W5u\xca\x1c\r\x0e\xa6&iS\x88[\x0c\x7f\xc4+\x16\x0c\x959nh\xafT\tr\xc9\t(\x0c\x95\x08hF\x86V5E\xc9\x0b\x06\x0c\x979bT\xa1V7c\xcb%-\r\x89\x15hX\xa2]1d\xcb0\x04\x0c\x96\x17hz\x85V4c\xc2\x0e\x01\x0f\xa9\x04hx\xa3T\x1bU\xc5\x13\x01\x07\x91>hW\xa8Z\x0eU\xc5\x11%\x00\x8c\x17dp\xb4T1g\xc2\x0e\x01\x0e\xb1;ka\xadW4W\xca)\x07\x0b\xad0'
# print(chushibiao[1],chushibiao[1]&127)
# print(chushibiao[2:4],chushibiao[4:8])
# 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]
    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

if payload == 126:
    extend_payload_len = hashstr[2:4]
    mask = hashstr[4:8]
    decoded = hashstr[8:]
# 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

if payload <= 125:
    extend_payload_len = None
    mask = hashstr[2:6]
    decoded = hashstr[6:]

# 当位运算结果小于等于125时,则这个数字就是数据的长度
# 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()
# b'\x81 \x85s \x92a\x10\x1b \xf7\r|\x1c' <126
for i in range(len(decoded)): # 0  \xf7 ^ \x92a 1 \r ^ \x10 \x1c ^ \x1b
    byte = decoded[i] ^ mask[i % 4]
    str_byte.append(byte)

print(str_byte.decode("utf8"))

加密方法:

import struct
msg_bytes = "the emperor has not been half-baked in the early days of the collapse of the road, today down three points, yizhou weakness, this serious crisis autumn".encode("utf8")
token = b"\x81" # + 数据长度/运算位 + mask/数据长度 + mask/数据 + 数据
length = len(msg_bytes)

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)