• flask框架4 表单验证, 表单查询wtforms,flask-migrate


    简单的表单验证      wtforms

    简单的表单验证.py

    from flask import Flask, render_template, request, redirect
    from wtforms import Form
    from wtforms.fields import simple
    from wtforms import validators
    from wtforms import widgets
    
    app = Flask(__name__, template_folder='templates')
    
    app.debug = True
    
    
    class LoginForm(Form):
        # 字段(内部包含正则表达式)
        name = simple.StringField(
            label='用户名',
            validators=[    # 检验规则
                validators.DataRequired(message='用户名不能为空.'),    # 错误信息
                validators.Length(min=6, max=18, message='用户名长度必须大于%(min)d且小于%(max)d')
            ],
            widget=widgets.TextInput(), # 页面上显示的插件类型
            render_kw={'class': 'form-control'} # 设定类属性,form-control 填满
    
        )
        # 字段(内部包含正则表达式)
        pwd = simple.PasswordField(
            label='密码',
            validators=[
                validators.DataRequired(message='密码不能为空.'),
                validators.Length(min=8, message='用户名长度必须大于%(min)d'),
                validators.Regexp(regex="^(?=.*[a-z])(?=.*[A-Z])(?=.*d)(?=.*[$@$!%*?&])[A-Za-zd$@$!%*?&]{8,}",
                                  message='密码至少8个字符,至少1个大写字母,1个小写字母,1个数字和1个特殊字符')
    
            ],
            widget=widgets.PasswordInput(),
            render_kw={'class': 'form-control'}
        )
    
    
    @app.route('/login', methods=['GET', 'POST'])
    def login():
        if request.method == 'GET':
            form = LoginForm()
            return render_template('login.html', form=form)
        else:
            form = LoginForm(formdata=request.form)    # request.form接收到的表单数据
            if form.validate(): # 判断数据是否合法
                print('用户提交数据通过格式验证,提交的值为:', form.data)
            else:
                print(form.errors)
            return render_template('login.html', form=form)
    
    if __name__ == '__main__':
        app.run()

    login.html

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
    <h1>登录</h1>
    <form method="post">
        <p>{{form.name.label}} {{form.name}} {{form.name.errors[0] }}</p>
    
        <p>{{form.pwd.label}} {{form.pwd}} {{form.pwd.errors[0] }}</p>
        <input type="submit" value="提交">
    </form>
    </body>
    </html>

     

    复杂的表单验证

    复杂的表单验证.py

    from flask import Flask, render_template, request, redirect
    from wtforms import Form
    from wtforms.fields import core
    from wtforms.fields import html5
    from wtforms.fields import simple
    from wtforms import validators
    from wtforms import widgets
    
    app = Flask(__name__, template_folder='templates')
    app.debug = True
    
    class RegisterForm(Form):
    
        def validate_pwd_confirm (self, field): # 钩子
            """
            自定义pwd_confirm字段规则,例:与pwd字段是否一致
            :param field:
            :return:
            """
            # 最开始初始化时,self.data中已经有所有的值
    
            if field.data != self.data['pwd']:  # field指代钩子函数中的pwd_confirm,所有数据都在self.data中
                raise validators.ValidationError("密码不一致") # 继续后续验证
                #raise validators.StopValidation("密码不一致123123123")  # 不再继续后续验证,不会执行下面的pwd_confirm equalto方法
    
        name = simple.StringField(
            label='用户名',
            validators=[
                validators.DataRequired()
            ],
            widget=widgets.TextInput(),
            render_kw={'class': 'form-control'},
            default='alex'  # 默认值
        )
    
        pwd = simple.PasswordField(
            label='密码',
            validators=[
                validators.DataRequired(message='密码不能为空.')
            ],
            widget=widgets.PasswordInput(),
            render_kw={'class': 'form-control'}
        )
    
        pwd_confirm = simple.PasswordField(
            label='重复密码',
            validators=[
                #validators.DataRequired(message='重复密码不能为空.'),
                validate_pwd_confirm,
                validators.EqualTo('pwd', message="两次密码输入不一致")  # 判断是否和pwd相等
            ],
            widget=widgets.PasswordInput(),
            render_kw={'class': 'form-control'}
        )
    
        email = html5.EmailField(
            label='邮箱',
            validators=[
                validators.DataRequired(message='邮箱不能为空.'),
                validators.Email(message='邮箱格式错误')
            ],
            widget=widgets.TextInput(input_type='email'),
            render_kw={'class': 'form-control'}
        )
    
        gender = core.RadioField(
            label='性别',
            choices=(
                (1, ''),
                (2, ''),
            ),
            coerce=int # “1” “2”    # 强制为int类型
         )
        city = core.SelectField(
            label='城市',
            choices=(
                ('bj', '北京'),
                ('sh', '上海'),
            )
        )
    
        hobby = core.SelectMultipleField(
            label='爱好',
            choices=(
                (1, '篮球'),
                (2, '足球'),
            ),
            coerce=int
        )
    
        favor = core.SelectMultipleField(
            label='喜好',
            choices=(
                (1, '篮球'),
                (2, '足球'),
            ),
            widget=widgets.ListWidget(prefix_label=False),
            option_widget=widgets.CheckboxInput(),
            coerce=int,
            default=[1, 2]
        )
    
        # def __init__(self, *args, **kwargs):
        #     super(RegisterForm, self).__init__(*args, **kwargs)
        #     self.favor.choices = ((1, '篮球'), (2, '足球'), (3, '羽毛球'))
    
    @app.route('/register', methods=['GET', 'POST'])
    def register():
        if request.method == 'GET':
            form = RegisterForm() # initial
            return render_template('register.html', form=form)
        else:
            form = RegisterForm(formdata=request.form)  # request.form接收到的表单数据
            if form.validate():
                print('用户提交数据通过格式验证,提交的值为:', form.data)
            else:
                print(form.errors)
            return render_template('register.html', form=form)
    
    
    if __name__ == '__main__':
        app.run()

    register.html

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
    <h1>用户注册</h1>
    <form method="post" novalidate style="padding:0  50px">
        {% for field in form %}
        <p>{{field.label}}: {{field}} {{field.errors[0] }}</p>
        {% endfor %}
        <input type="submit" value="提交">
    </form>
    </body>
    </html>

     

    flask的ORM  sqlalchemy

    SQLAlchemy是一个基于Python实现的ORM框架。该框架建立在 DB API之上,使用关系对象映射进行数据库操作,简言之便是:将类和对象转换成SQL,然后使用数据API执行SQL并获取执行结果。

    SQLAlchemy本身无法操作数据库,其必须以来pymsql等第三方插件,Dialect用于和数据API进行交流,根据配置文件的不同调用不同的数据库API,从而实现对数据库的操作

    注意:sqlalchemy不支持改表,只能删除表后再创表

    简单的表单查询

    models文件:

    import datetime
    from sqlalchemy import create_engine
    from sqlalchemy.ext.declarative import declarative_base
    from sqlalchemy import Column, Integer, String, Text, ForeignKey, DateTime, UniqueConstraint, Index
    from sqlalchemy.orm import relationship
    Base = declarative_base()
    
    class Users(Base):
        __tablename__ = 'users'  # 数据库表名称
        id = Column(Integer, primary_key=True)  # id 主键
        name = Column(String(32), index=True, nullable=False)  # name列,index索引,不可为空
        age = Column(Integer)
        # email = Column(String(32), unique=True)
        #datetime.datetime.now不能加括号,加了括号,以后永远是当前时间
        # ctime = Column(DateTime, default=datetime.datetime.now)
        # extra = Column(Text, nullable=True)
    
        __table_args__ = (
            # UniqueConstraint('id', 'name', name='uix_id_name'), #联合唯一
            # Index('ix_id_name', 'name', 'email'), #索引
        )
    
        def __repr__(self): # 更为底层,如果为__str__不能清晰显示
            return self.name
    
    class Hobby(Base):
        __tablename__ = 'hobby'
        id = Column(Integer,primary_key=True)
        caption = Column(String(50),default='双色球')
    
    class Person(Base):
        __tablename__ = 'person'
        nid = Column(Integer,primary_key=True)
        name = Column(String(32))
        # hobby是tablename而不是Hobby类名
        hobby_id = Column(Integer,ForeignKey('hobby.id'))
    
        # 更新数据库没有关系,不会信增加字段,只能用于快速的链表查询操作
        # relationship的第一个参数,是类名,第二个参数backref,用于反向查询
        hobby = relationship('Hobby',backref='pres')
        def __repr__(self):
            return self.name
    
    class Boy2Girl(Base):
        __tablename__ = 'boy2girl'
        id = Column(Integer,primary_key=True)
        girl_id = Column(Integer,ForeignKey('girl.id'))
        boy_id = Column(Integer,ForeignKey('boy.id'))
    
    class Girl(Base):
        __tablename__ = 'girl'
        id = Column(Integer,primary_key=True)
        name = Column(String(100),nullable=False)
    
        def __repr__(self):
            return self.name
    
    class Boy(Base):
        __tablename__ = 'boy'
        id = Column(Integer,primary_key=True)
        name = Column(String(100),nullable=False)
        # secondary=boy2girl 为中间表的表名
        girl = relationship('Girl',secondary='boy2girl',backref='boys')
    
        def __repr__(self):
            return self.name
    
    def init_db():
        """
        根据类创建数据库表
        :return:
        """
        engine = create_engine(
            "mysql+pymysql://root:@127.0.0.1:3306/day95?charset=utf8",
            # "什么数据库(mysql,orcal)+用什么取链接数据库(pymysql)://数据库用户名:密码@mysqlip:端口/数据库名?charset=字符集"
            max_overflow=0,  # 超过连接池大小外最多创建的连接
            pool_size=5,  # 连接池大小
            pool_timeout=30,  # 池中没有线程最多等待的时间,否则报错
            pool_recycle=-1  # 多久之后对线程池中的线程进行一次连接的回收(重置)
        )
    
        Base.metadata.create_all(engine)    # 创建数据库
    
    def drop_db():
        """
        根据类删除数据库表
        :return:
        """
        engine = create_engine(
            "mysql+pymysql://root:@127.0.0.1:3306/day95?charset=utf8",
            max_overflow=0,  # 超过连接池大小外最多创建的连接
            pool_size=5,  # 连接池大小
            pool_timeout=30,  # 池中没有线程最多等待的时间,否则报错
            pool_recycle=-1  # 多久之后对线程池中的线程进行一次连接的回收(重置)
        )
    
        Base.metadata.drop_all(engine)  # 删除数据库
    
    if __name__ == '__main__':  # sqlalchemy不支持该表,只能删除表后再创表
        drop_db()
        init_db()

    orm.py

    from sqlalchemy.orm import sessionmaker
    from sqlalchemy import create_engine
    from models import Users
    #"mysql+pymysql://root@127.0.0.1:3306/aaa"
    engine = create_engine("mysql+pymysql://root:@127.0.0.1:3307/python13", max_overflow=0, pool_size=5)
    Connection = sessionmaker(bind=engine)
    
    # 每次执行数据库操作时,都需要创建一个Connection
    con = Connection()
    
    # 1 单增
    
    # obj1  = Users(name="lsb1",age=12)
    # con.add(obj1)
    
    # 2 多个增加
    
    # con.add_all([
    #          Users(name="lsb1",age=12),
    #         Users(name="esb",age=40),
    #         Users(name="jsb",age=30),
    #         Users(name="tsb",age=12),
    #         #Host(name = "tsb",time=123213)
    # ])
    
    
    
    # 3 删除
    # con.query(Users).delete()
    
    
    #4 改
    # con.query(Users).update({"name":"sb","age":14})    # 要传字典
    
    # 如果拼接是字符串,此处要设置synchronize_session=False
    # con.query(Users).update({Users.name:Users.name +" is true","age":1},synchronize_session=False)
    
    # con.query(Users).update({Users.age:Users.age + 10})
    
    # 5查(查是不需要commit,也能拿到结果)
    #打印sql
    # r1 = con.query(Users)
    
    #查询所有
    # r1 = con.query(Users).all()
    #
    #查单条记录
    # r1  = con.query(Users).first()
    
    #查哪些字段
    # r1  = con.query(Users.age,Users.name.label("sb")).first()    # 起别名sb 打印要用print(r1.sb)
    
    #过滤用filter_by(传参数)或者filter(传表达式)
    # r1 = con.query(Users).filter(Users.name == "tsb").first()
    # con.query(Users).filter(Users.name == "tsb").update({"name": "sb", "age": 14})
    
    
    r1 =  con.query(Users).filter_by(name = "esb").first()
    
    print(r1)
    
    #必须提交才能生效
    con.commit()
    
    #关闭链接
    con.close()

    单表查询

    from sqlalchemy.orm import sessionmaker
    from sqlalchemy import create_engine
    from models import Users
    #"mysql+pymysql://root@127.0.0.1:3306/aaa"
    engine = create_engine("mysql+pymysql://root:@127.0.0.1:3307/python13", max_overflow=0, pool_size=5)
    Connection = sessionmaker(bind=engine)
    
    # 每次执行数据库操作时,都需要创建一个Connection
    session = Connection()
    
    # 条件
    # ret =  session.query(Users).filter_by(name = "esb").all()
    
    #表达式,and 条件链接
    # ret  = session.query(Users).filter(Users.name == "sb",Users.age ==14 ).first()
    # print(ret.age,ret.name)
    
    # 表示的between,条件,30<=age<=40
    # ret  = session.query(Users).filter(Users.age.between(30,40)).all()
    # print(ret)
    
    # sql查询的in_操作,相当于django中的__in
    # ret =session.query(Users).filter(Users.id.in_([9,11,13])).all()
    # print(ret)
    # # sql查询取反
    # ret1 = session.query(Users).filter(~Users.id.in_([9,11,13])).all()
    # print(ret1)
    
    
    #or查询 ,or和and ,做整合
    from sqlalchemy import or_,and_
    
    # ret =  session.query(Users).filter(or_(Users.id == 9,Users.name=="jsb")).all()
    # ret =  session.query(Users).filter(and_(Users.id == 9,Users.name=="lsb1")).all()
    
    # ret =  session.query(Users).filter(or_(
    #     Users.id == 9,
    #     and_(Users.name=="jsb",Users.id==13),
    #
    #     )
    # ).all()
    
    # like查询,        # _代表一个字符,%代表任意字符
    #必须以b开头
    # ret = session.query(Users).filter(Users.name.like("b%")).all()
    # #第二字母是b
    # ret = session.query(Users).filter(Users.name.like("_b%")).all()
    #不以b开头
    # ret = session.query(Users).filter(~Users.name.like("b%")).all()
    
    #排序
    #desc重大到小排序
    # ret = session.query(Users).filter(Users.id>1).order_by(Users.id.desc()).all()
    #desc重小到大排序
    #ret = session.query(Users).filter(Users.id>1).order_by(Users.id.asc()).all()
    #多条件排序,先以年纪从大到小排,如果年龄相同,再以id从小到大排
    # ret = session.query(Users).filter(Users.id>1).order_by(Users.age.desc(),Users.id.asc()).all()
    # print(ret)
    
    
    #分组查询
    # ret  = session.query(Users).group_by(Users.name).all()
    
    # 再分组的时候如果要用聚合操作,就要导入func
    from sqlalchemy.sql import func
    #选出组内最小年龄要大于等于30的组
    # ret  = session.query(Users).group_by(Users.name).having(func.min(Users.age)>=30).all()
    
    #选出组内最小年龄要大于等于30的组,查询组内的最小年龄,最大年纪,年纪之和,
    ret = session.query(
        func.min(Users.age),    # 显示组中最小值
        func.max(Users.age),
        func.sum(Users.age),
        Users.name
    ).group_by(Users.name).having(func.min(Users.age)>=30).all()
    print(ret)

    一对多关联

    from sqlalchemy.orm import sessionmaker
    from sqlalchemy import create_engine
    from models import Hobby,Person
    #"mysql+pymysql://root@127.0.0.1:3306/aaa"
    engine = create_engine("mysql+pymysql://root:@127.0.0.1:3307/python13", max_overflow=0, pool_size=5)
    Connection = sessionmaker(bind=engine)
    
    # 每次执行数据库操作时,都需要创建一个Connection
    session = Connection()
    
    #1添加,没有用关联关系
    # session.add_all([
    #     Hobby(catption="淫诗"),
    #     Hobby(catption="推背"),
    #     Person(name="tank",hobby_id=1),
    #     Person(name="jason",hobby_id=2)
    # ])
    
    # 2添加 用关联关系
    # preson = Person(name="egon",hobby=Hobby(catption="相亲"))
    #session.add(preson)
    #
    # hobb = Hobby(catption="人妖")
    # hobb.pres = [Person(name="owen"),Person(name="sean")]
    # session.add(hobb)
    
    #session.commit()
    
    #正向查询
    # pr = session.query(Person).filter( Person.name == "tank").first()
    # print(pr.name)
    # print(pr.hobby.catption)
    
    
    #反向查
    # v = session.query(Hobby).filter(Hobby.catption=="人妖").first()
    # print(v.catption)
    # print(v.pres)
    
    
    # 如果没用foreign key,为断关联。自己连表,isouter=True表示是left join,不填默认为inner join
    person_list =  session.query( Hobby).join(Person,Person.hobby_id==Hobby.id,isouter=True)
    #
    print(person_list)
    
    
    session.close()

    多对多

    from sqlalchemy.orm import sessionmaker
    from sqlalchemy import create_engine
    from models import Boy,Boy2Girl,Girl
    #"mysql+pymysql://root@127.0.0.1:3306/aaa"
    engine = create_engine("mysql+pymysql://root:@127.0.0.1:3307/python13", max_overflow=0, pool_size=5)
    Connection = sessionmaker(bind=engine)
    
    # 每次执行数据库操作时,都需要创建一个Connection
    session = Connection()
    
    #添加
    # session.add_all([    
    #     Boy(name="tank"),
    #     Boy(name="sean"),
    #     Girl(name="仓老师"),
    #     Girl(name="小泽老师")
    # ])
    
    # b2g = Boy2Girl(boy_id=1,girl_id=2)
    # session.add(b2g )
    # b2g = Boy2Girl(boy_id=2,girl_id=1)
    # session.add(b2g )
    # session.commit()
    # session.close()
    
    # 关联添加
    # boy = Boy(name="亚峰")
    # boy.girl=[Girl(name="迪丽热巴"),Girl(name="三上")]
    # session.add(boy)
    # session.commit()
    
    #
    # girl = Girl(name="丹丹")
    # girl.boys=[Boy(name="吴彦祖"),Boy(name="鹿晗")]
    # session.add(girl)
    # session.commit()
    
    # 使用relationship的关系,正向查
    # b = session.query(Boy).filter(Boy.name == "亚峰").first()
    # print(b.name)
    # print(b.girl)
    
    #反向查询
    # g = session.query(Girl).filter(Girl.name=="丹丹").first()
    # print(g.name)
    # print(g.boys)

    flask-migrate

     flask_sqlalchemy是flask和SQLAchemy的管理者,通过他把他们做连接的ORM

    flask_sqlalchemy

    要用就必须先安装。
    pip install flask-sqlalchemy
    所有的到导入都找 下面的db
    from flask_sqlalchemy import SQLAlchemy
    db = SQLAlchemy()

    flask_migrate       数据库迁移命令

    安装
    pip install flask-migrate
    
    命令:manager.add_command('db1', MigrateCommand)
    1 当项目第一次执行迁移的时候。
    python3 manage.py db1 init 只需要初始化一次
    
    2 python3 manage.py db1 migrate # 等同于django的makemigrations
    
    3 python3 manage.py db1 upgrade # 等同于django的migrate
    
    启动项目 python manage.py runserver

    示例:

    settings.py

    class BaseConfig(object):
        # SESSION_TYPE = 'redis'  # session类型为redis
        # SESSION_KEY_PREFIX = 'session:'  # 保存到session中的值的前缀
        # SESSION_PERMANENT = True  # 如果设置为False,则关闭浏览器session就失效。
        # SESSION_USE_SIGNER = False  # 是否对发送到浏览器上 session:cookie值进行加密
    
        SQLALCHEMY_DATABASE_URI = "mysql+pymysql://root:@127.0.0.1:3306/day95?charset=utf8"
        SQLALCHEMY_POOL_SIZE = 5
        SQLALCHEMY_POOL_TIMEOUT = 30
        SQLALCHEMY_POOL_RECYCLE = -1
    
        # 追踪对象的修改并且发送信号
        SQLALCHEMY_TRACK_MODIFICATIONS = False

    manage.py

    """
    必须 pip install flask-migrate,,为管理数据库的版本
    flask-sqlalchemy,这个orm
    
    """
    
    from sansa import create_app
    from flask_script import Manager
    # flask_migrate管理数据迁移的
    from flask_migrate import Migrate,MigrateCommand
    from sansa import db
    app = create_app()
    manager=Manager(app)
    
    # 将当前app,与db注册到Migrate
    Migrate(app,db)
    # 添加管理数据的命令
    manager.add_command('db1', MigrateCommand)
    
    if __name__ == '__main__':
        # app.run()
        manager.run()

    sansa/models.py

    from . import db
    
    class Users(db.Model):
        """
        用户表
        """
        __tablename__ = 'users'
        id = db.Column(db.Integer, primary_key=True)
        username = db.Column(db.String(80), unique=True, nullable=False)
        email = db.Column(db.String(120), unique=True, nullable=False)
        ids = db.Column(db.Integer)
    
        def __repr__(self):
            return '<User %r>' % self.username

    sansa/__init__.py

    from flask import Flask
    from flask_sqlalchemy import SQLAlchemy
    db = SQLAlchemy()
    
    # from .models import *
    from .views import account
    
    def create_app():
        app = Flask(__name__)
        app.config.from_object('settings.BaseConfig')
    
        # 将db注册到app中
        db.init_app(app)
    
        # 注册蓝图
        app.register_blueprint(account.account)
    
        return app

    sansa/views/account.py

    from flask import Blueprint
    from .. import db
    from .. import models
    
    account = Blueprint('account', __name__)
    
    @account.route('/login')
    def login():
        # db.session.add(models.Users(username='lqz', email='123'))
        #db.session.query(models.Users).all()
        # db.session.commit()
        # 添加示例
       
        user_list = db.session.query(models.Users).all()
    
        for item in user_list:
            print(item.username,"is",item.email)
    
        return 'login'
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  • 原文地址:https://www.cnblogs.com/ludingchao/p/12554879.html
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