Flask-session,WTForms,POOL,Websocket通讯原理 -握手,加密解密过程

1.Flask-session

Flask中的session 需要执行 session_interface - open_session
存储到redis中,存的key:session:d3f07db2-940b-4ee3-adfb-cdd7956dd921(前端浏览器里session的vlaue)

from flask import Flask, session
from flask_session import Session
from redis import Redis

app = Flask(__name__)
# app.secret_key = "asdasd"
app.config["SESSION_TYPE"] = "redis"
app.config["SESSION_REDIS"] = Redis(host="127.0.0.1", port=6379, db=6)

Session(app)

@app.route("/")
def index():
    session["user"] = "1111111"
    return "hello"

@app.route("/go")
def go():
    print(session.get("user"))
    return "ok"


if __name__ == '__main__':
    app.run("0.0.0.0", 5000, debug=True)

2.WTForms

类似django的modelform

.py

from flask import Flask, request, render_template
from wtforms import Form
from wtforms.fields import simple, core
from wtforms import validators


app = Flask(__name__)


class LoginFrom(Form):
    username = simple.StringField(
        # 标签标记
        label="用户名",
        # 校验条件,可迭代对象
        validators=[validators.DataRequired(message="用户名不能为空"),
                    validators.Length(min=3, max=8, message="密码必须在3-8位之间")],
        # 标签id
        id="user_name",
        # 默认值
        default=None,
        # 默认组件(input type="text") 在StringField中已经被实例化了
        widget=None,
        # 标签属性
        render_kw={"class": "login"}
    )
    password = simple.PasswordField(
        label="密码",
        validators=[validators.DataRequired(message="密码不能为空"),
                    validators.Length(min=6, max=16, message="密码必须在6-16位之间"),
                    validators.Email(message="密码必须为邮箱格式")],
        id="pwd",
        default=None,
        # simple.PasswordField里面为我们设置了widget为widgets.PasswordInput()
        widget=None,
        render_kw={"class": "login"}
    )


class RegForm(Form):
    username = simple.StringField(
        label="用户名",
        validators=[validators.DataRequired(message="用户名不能为空"),
                    validators.Length(min=3, max=8, message="密码必须在3-8位之间")]
    )
    password = simple.PasswordField(
        label="密码",
        validators=[validators.DataRequired(message="密码不能为空"),
                    validators.Length(min=6, max=16, message="密码必须在6-16位之间"),
                    validators.Email(message="密码必须为邮箱格式")],
    )
    repassword = simple.PasswordField(
        label="确认密码",
        validators=[validators.EqualTo(fieldname="password", message="两次密码不一致!")]
    )
    gender = core.RadioField(
        label="性别",
        coerce=str,
        choices=(
            ("1", ""),
            ("2", "")
        ),
        default="1"
    )
    hobby = core.SelectMultipleField(
        label="爱好",
        validators=[validators.Length(min=2, max=4, message="请选择2-4个爱好")],
        coerce=int,
        choices=(
            (1, "fengjie"),
            (2, "luoyufeng"),
            (3, "lixueqin"),
            (4, "wuyifan"),
            (5, "panta")
        ),
        default=(1, 3, 5)
    )


@app.route("/login", methods=["GET", "POST"])
def login():
    if request.method == "GET":
        fm = LoginFrom()
        return render_template("login.html", fm=fm)
    else:
        fm = LoginFrom(request.form)
        if fm.validate():
            return "登录成功" + request.form.get("password")
        else:
            return render_template("login.html", fm=fm)


@app.route("/reg", methods=["GET", "POST"])
def reg():
    if request.method == "GET":
        fm = RegForm()
        return render_template("reg.html", fm=fm)
    else:
        fm = RegForm(request.form)
        if fm.validate():
            print(type(fm.data.get("gender")), fm.data.get("gender"))
            return "登录成功" + request.form.get("password")
        else:
            return render_template("reg.html", fm=fm)


if __name__ == '__main__':
    app.run("0.0.0.0", 5000, debug=True)

.html

login
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="" method="post" novalidate>
    {{ fm.username.label }}
    {{ fm.username }}
    <p><h1>{{ fm.username.errors.0}}</h1></p>
    {{ fm.password.label }}
    {{ fm.password }}
    <p><h1>{{ fm.password.errors.0 }}</h1></p>
    <input type="submit" value="登录">
</form>
</body>
</html>
reg
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="" method="post" novalidate>
    {% for field in fm %}
        <p>{{ field.label }}{{ field }}{{ field.errors.0 }}</p>
    {% endfor %}
    <input type="submit" value="注册">
</form>
</body>
</html>

3.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="day"
)

conn = POOL.connection() # pymysql - conn
cur = conn.cursor(cursor=pymysql.cursors.DictCursor) #游标,用于查询(里面的参数会将查询结果优化)
sql = "select * from users WHERE name='jwb' and age=73"
res = cur.execute(sql) #有几行响应
print(res)
print(cur.fetchall())
conn.close()

4.sqlhelper

import pymysql
from dbpool import POOL


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))

5.websocket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

Host: 127.0.0.1:9527

Connection: Upgrade

Pragma: no-cache

Cache-Control: no-cache

User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.81 Safari/537.36

Upgrade: websocket

Origin: http://localhost:63342

Sec-WebSocket-Version: 13

Accept-Encoding: gzip, deflate, br

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

Cookie: session=d3f07db2-940b-4ee3-adfb-cdd7956dd921

Sec-WebSocket-Key: JScC6nJU67n3fwkp2LdA0w==

Sec-WebSocket-Extensions: permessage-deflate; client_max_window_bits


"""
# 以下动作是有websockethandler完成的
# magic string为:258EAFA5-E914-47DA-95CA-C5AB0DC85B11


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


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)
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
" 
               "Upgrade:websocket
" 
               "Connection: Upgrade
" 
               "Sec-WebSocket-Accept: %s
" 
               "WebSocket-Location: ws://127.0.0.1:9527

"
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)

6.解密

#b'x81x89xf3x99x81-x15x05x01xcbOx1bex97]'
#b'x81x85sx92ax10x1bxf7
|x1c'
#b'x81x83Hxc0xxa6yxf2K'

hashstr = b'x81x85sx92ax10x1bxf7
|x1c'
# b'x81 x85s x92ax10x1bxf7  
|x1c' <126
# x85s = 5
hashstr = b'x81xfex02xdcx8dxe8-xb2hmxa5W5uxc8:x16x0cx95(ktx87Wx00bxc52x01x0cx95x1fdixbeW9Axcbx1cx0fx07x91>iSxa7W)Axc9
x06x0cx95;h`xab]1dxca)x07
x9a,j~x9fW1bxc2x0ex01x0ex80x16eGxb7Wx00Yxcb2(
x80*iRx8cV4cxcax15x06x0cx94-nhxafU	^xc9x0cx00
xa0x19iQxa6Z
Kxc9
x00x0exaa:iRxa3Wx0bmxc2x0ex01
x92x12hWxbaV4cxc8x11&
x92*eRx86V7fxc8x16x1bx00xad7bTxa1Ux16~xc5
0
xa8:hPxb0V4cxcbx1cx07x01xac5bTxa1T!Zxcb8(x0cx949iRxa3[x14sxc9
x06x0cx94-nhxafZ"rxc8x1cx11
x912hTx8dWx11Kxc8"!x07x91>iSx88Wx08axc87x05
x95/dixbaW3_xc2x0ex01x0exacx10hTxb5W2x7fxc8x11&x0cx949kXxb9]1dxc9
x00
x83.hNxa9Z
Bxc5=?x00xbb6bTxa1W1}xc8$6
x89x03iQxa4]1dxc9	(
x8c,hWx8dZ=gxc9x0bx06x00x9ax1diQxb2Q
jxc8x1c&x0cx95x1fhRxb1V5Exc2x0ex01x0cx92x03iPx97V5hxc9x0fx1ex07x91>dqxb2U0rxc55*
xbdx14bTxa1V5exc8x1cx11
x910hxxa1Q
jxc59(x0exb1;iUxb1W(Pxca8"x0fx8a#hgxa7V5Rxc8
-
xbb6ehxa8]1dxc8x1cx11x0cx96*ktxa4Wx02Pxc5x1c7
xa8x04h`xbcZ8gxc2x0ex01x0cx96x17kpx80[x14sxc9
x06
x94x01kpxa3V4cxca"x0bx07x91>iPxa0W#txc83x02x0fx8a3bTxa1V0Wxc84x08
x89$hTxafT>}xc9x0bx12x0bxad0iVxa0V5Exce2x0cx0cx93?dkxa3[x0eExcb&5x0cx949nhxacZ9Qxcax17x03x0bxad3eyx8eWx08ixcax1fx04x07x91>kEx89Ux17nxc5;"
x83,bTxa1W2x7fxc5+x1c
x92x12jRx82]1dxcb*"x0cx96x17hmxa5W5uxcax1c
x0exa6&iSx88[x0cx7fxc4+x16x0cx959nhxafT	rxc9	(x0cx95x08hFx86V5Exc9x0bx06x0cx979bTxa1V7cxcb%-
x89x15hXxa2]1dxcb0x04x0cx96x17hzx85V4cxc2x0ex01x0fxa9x04hxxa3Tx1bUxc5x13x01x07x91>hWxa8Zx0eUxc5x11%x00x8cx17dpxb4T1gxc2x0ex01x0exb1;kaxadW4Wxca)x07x0bxad0'
# 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 x92ax10x1b xf7
|x1c' <126
for i in range(len(decoded)): # 0  xf7 ^ x92a 1 
 ^ x10 x1c ^ x1b
    byte = decoded[i] ^ mask[i % 4]
    str_byte.append(byte)

print(str_byte.decode("utf8"))

7.加密

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)
原文地址:https://www.cnblogs.com/qq849784670/p/10274068.html