flask的CBV,flash,Flask-Session,及WTForms-MoudelForm

1,CBV:

• from flask import vews
• class LoginView(views.MethodView):
  • def get(self):
    • return "雪雪其实也很好,"
  • def post(self):
    • return "听说雪人很要走了,那些等有机会,等有时间,都觉的遥远了"
• app.add_url_rule("/login", endpoint=None, view_func=LoginView.as_view("login"))

2,flask:

• from flask import flask,get_flash_messages
• flash("雪雪", "tag")   # 闪存
• get_flash_messages("tag")

3,Flask-Session

• from flask_session import Session
• from flask import session
• app.config["SESSION_TYPE"] = "redis"
• app.config["SESSION_REDIS"] = Redis("127.0.0.1", 6379, db=7)
• Session(app)

4,WTForms - MoudelForm

• from wtfroms.field import simple,core
• from wtforms import Form,validators
• class LoginForm(Form):
  • username = simple.StringField(label= "用户名")
• loginForm = LoginForm()
• render_template("login.html", loginForm=loginForm)
• {{ loginForm.username }}
• {{ loginForm.password }}
• {{ loginForm.username.errors.0 }}
• loginForm = LoginForm(request.forms)
• if not loginForm.validata():
  • render_template("login.html", loginForm)

具体代码:

CBV的写法:

from flask import Flask, flash, get_flashed_messages,render_template
from flask import views
# 实例化Flask对象
app = Flask(__name__)  # type: Flask
app.secret_key = "miss"

@app.route("/")
def index():
    # 这个flash取完值就没有了,一次性的事
    flash("xuexue", "小老弟")
    flash("xiaoxue")
    return "我的头可不是面团捏的!!!"

# CBV的写法
class LoginClass(views.MethodView):
    # get请求的方法
    def get(self):
        print(get_flashed_messages("小老弟"))
        print(get_flashed_messages())
        return render_template("login.html")

    # 提交数据的方法
    def post(self):
        return "来了, 老弟~~~"

# 注册路由
app.add_url_rule("/login", view_func=LoginClass.as_view("login"))

@app.before_first_request
def asd():
    # 在这根据flash判断是不是第一次请求
    # 第一次请求,就把flash的值取走,
    print("bf1")
    return "不知道该写什么了..."

if __name__ == '__main__':
    app.run(debug=True)

APP-flask-Session

from flask import Flask,render_template, redirect, session
from flask import views
from redis import Redis  # 这个必须写,重新封装Redis的时候用
from flask_session import Session  # 用了这个Session就不用指定secret_key = xxxx
# 实例化一个 Flask对象
app = Flask(__name__)  # type:Flask
app.config["SESSION_TYPE"] = "redis"
app.config["SESSION_REDIS"] = Redis("127.0.0.1", 6379, db=7)  # db表示能开几个服务
# 实例化一个Session的对象把Flask数理化的对象传进去,就不用指定secret_key=xxx了
Session(app)

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

    return "雪人哈哈哈哈哈~~~~"

class LoginClass(views.MethodView):

    def get(self):
        print(session.get("user"))
        # 7b97e0ef-2a14-4725-842e-848fde4d2f15
        # 和uuid的值特别的像
        return render_template("login.html")

    def post(self):
        return "啧啧啧..."

app.add_url_rule("/login", view_func=LoginClass.as_view("login"))

if __name__ == '__main__':
    app.run(debug=True)

app的视图函数

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

# CBV的写法
# 指定登录的类继承Form
class LoginForm(Form):
    # 定义校验的字段
    username = simple.StringField(
        label="用户名",
        # 要校验该字段的内容
        validators=[
            validators.DataRequired(message="不能为空"),
            validators.Length(min=5, max=10, message="用户名不能小于5个字符求不能大于10个字符")
        ],
        # widget=widgets.TextInput
        render_kw={"class": "my_username"}  # 在标签上加一个样式类
    )
    password = simple.PasswordField(
        label="密码",
        # 要校验该字段的内容
        validators=[
            validators.DataRequired(message="不能为空"),
            validators.Length(min=6,message="密码最少要6位"),
            validators.Length(max=12, message="密码至多12位"),
            validators.Regexp(regex="\d+", message="密码必须是纯数字"),
        ],
        render_kw={"class": "my_password"}
    )

# 注册的Form
class RegisterForm(Form):
    username = simple.StringField(
        label="用户名",
        validators=[
            validators.DataRequired(message="用户名不能为空"),
        ],
        render_kw={"class": "my_username"}
    )
    nickname = simple.StringField(
        label="昵称",
        validators=[
            validators.DataRequired(message="昵称不能为空")
        ],
        render_kw={"class": "my_username"}
    )
    password = simple.PasswordField(
        label="密码",
        validators=[
            validators.DataRequired(message="密码不能为空"),
            validators.Length(min=6, max=12, message="密码大于6小于12"),
            validators.Regexp(regex="\d+", message="密码必须是数字"),
        ],
        render_kw={"class": "my_password"}
    )
    re_password = simple.PasswordField(
        label="重复密码",
        validators=[
            validators.EqualTo(fieldname="password",message="两次密码不一致"),
        ],
    )
    email = simple.StringField(
        label="邮箱",
        validators=[
            validators.Email(message="格式不正确"),
        ],
        render_kw={"class": "my_email"}
    )
    gender = core.RadioField(
        label="性别",
        coerce=int,  # 拿到的是性别在数据库中的前边数字
        choices=(
            (1, "女"),
            (2, "男"),
        ),
        default=1  # 设置默认值为1
    )
    hobby = core.SelectMultipleField(
        label="爱好",
        coerce=int,
        choices=(
            (1, "烤串"),
            (2, "烤面包片"),
            (3, "烤鱼"),
            (4, "pizza"),
            (5, "蝎王府"),
        ),
        default=(3,5)
    )
# 实例化一个Flask的对象
app = Flask(__name__)  # type:Flask

@app.route("/")
def index():
    return "我的头可不是面团捏的"

# 登录页面
class LoginView(views.MethodView):
    def get(self):
        loginForm = LoginForm()
        return render_template("login.html", loginForm=loginForm)

    def post(self):
        # 将获取到的数据放到LoginForm中进行
        loginForm = LoginForm(request.form)
        # 通过校验的数据
        if loginForm.validate():
            return "登录成功"
        else:
            return render_template("login.html", loginForm=loginForm)

app.add_url_rule("/login", view_func=LoginView.as_view("login"))

# 注册的业务逻辑函数
class RegisterView(views.MethodView):
    def get(self):
        # 实例化注册的校验类
        regForm = RegisterForm()
        if regForm.validate():
            return "注册通过了校验"
        else:
            return render_template("register.html", regForm=regForm)

    def post(self):
        regForm = RegisterForm(request.form)
        if regForm.validate():
            return "通过校验的数据"
        else:
            return render_template("register.html", regForm=regForm)

app.add_url_rule("/register", view_func=RegisterView.as_view("register"))

if __name__ == '__main__':
        app.run(debug=True)

5,DBUtils数据连接池

import pymysql
from DBUtils.PooledDB import PooledDB
# 实例化pooleDB对象
POOL = PooledDB(
    creator=pymysql,  # 使用连接数据库的模块
    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,连接池中至少创建的空闲的连接,0表示不创建
    maxcached=5, # 连接池中最多闲置的连接, 0和None不限制
    maxshared=3,  # 连接池中最多共享的连接数量, 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,maxacahed永远为0,所以永远是共享所有连接都共享
    blocking=True,  # 连接池中如果没有可用连接,是否阻塞等待.True,等待,False,不等待然后报错
    maxusage=None,  # 一个连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 = nerver, 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="123456",
    database="test",
    charset="utf8"
)

def func():
    # 在连接池中连接
    conn = POOL.connection()
    # 油表使用辟谣mysql
    cursor = conn.cursor(pymysql.cursors.DictCursor)
    # 从表中查询数据
    cursor.execute('select * from xueren ')
    result = cursor.fetchall()
    print(result)
    conn.close()

func()

from DBUtils.PooledDB import PooledDB
import pymysql

class MySQLhelper(object):
    def __init__(self, host, port, dbuser, password, database):
        self.pool = PooledDB(
            creator=pymysql,  # 使用连接数据库的模块
            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,连接池中至少创建的空闲的连接,0表示不创建
            maxcached=5,  # 连接池中最多闲置的连接, 0和None不限制
            maxshared=3,
            # 连接池中最多共享的连接数量, 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,maxacahed永远为0,所以永远是共享所有连接都共享
            blocking=True,  # 连接池中如果没有可用连接,是否阻塞等待.True,等待,False,不等待然后报错
            maxusage=None,  # 一个连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 = nerver, 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="123456",
            database="test",
            charset="utf8"
        )

    # 创建连接油表
    def create_conn_cursor(self):
        conn = self.pool.connection()
        cursor = conn.cursor(pymysql.cursors.DictCursor)
        return conn, cursor

    # 获取所有的数据(从数据库中)
    def fetch_all(self, sql, args):
        conn, cursor = self.create_conn_cursor()
        cursor.execute(sql, args)
        result = cursor.fetchall()
        cursor.close(
        )

    # 插入数据
    def insert_one(self, sql, args):
        conn, cursor = self.create_conn_cursor()
        res = cursor.execute(sql, args)
        conn.commit()
        print(res)
        conn.close()
        return res

    # 更新数据
    def update(self, sql, args):
        conn,cursor = self.create_conn_cursor()
        res = cursor.execute(sql, args)
        conn.commit()
        print(res)
        conn.close()
        return res

sqlhelper = MySQLhelper("127.0.0.1", 3306, "root", "", "test")

# 查询表里所有的数据
res = sqlhelper.fetch_all("select * from xueren where id=%s", (1,))
print(res)

# 插入数据
# res = sqlhelper.insert_one("insert into xueren VALUES (%s,%s %s)", (1, "miss", "really"))
# print(res)
# 更新数据
# res = sqlhelper.update("update user SET name=%s WHERE id=%s", ("哈哈哈"))