完成登录功能，用session记住用户名

登录功能完成：

1. js:设置return
2. html:设置
   1. form
   2. input
3. py:
   1. @app.route设置methods
   2. GET
   3. POST
      1. 读取表单数据
      2. 查询数据库
         1. 用户名密码对：
            1. 记住用户名
            2. 跳转到首页
         2. 用户名密码不对：
            1. 提示相应错误。

session：

1. 从`flask`中导入`session`
2. 设置`SECRET_KEY`
3. 操作字典一样操作`session`：增加用户名`session['username']=`username

 

import os

SECRET_KEY=os.urandom(24)

SQLALCHEMY_DATABASE_URI = 'mysql+pymysql://root:@localhost:3306/misdb?charset=utf8'
SQLALCHEMY_TRACK_MODIFICATIONS = False

 

from flask import Flask,render_template,request,redirect,url_for,session
from flask_sqlalchemy import SQLAlchemy
import config
from functools import wraps
from datetime import datetime

app=Flask(__name__)
app.config.from_object(config)
db=SQLAlchemy(app)

class User(db.Model):
    __tablename__='user'
    id=db.Column(db.Integer, primary_key=True,autoincrement=True)
    username = db.Column(db.String(20), nullable=False)
    password = db.Column(db.String(20), nullable=False)
    nickname = db.Column(db.String(50))

# db.create_all()

# 添加/删除
# user=User.query.filter(User.username=='mis1',password='mis1')
# db.session.add/delete(user)
# db.session.commit()
# 查询
# user=User.query.filter(User.username =='mis1').first()
# print(user.username,user.password)
# 修改
# user=User.query.filter(User.username=='mis1').first()
# user.password='123456'
# user.username='mis1'
# print(user.username,user.password)
# db.session.commit()

@app.route('/')
def base():
    return render_template('base.html')

@app.route('/regist/',methods=['GET','POST'])
def regist():
    if request.method=='GET':
        return render_template('regist.html')
    else:
        username=request.form.get('username')
        password=request.form.get('password')
        nickname = request.form.get('nickname')
        user = User.query.filter(User.username==username).first()
        if user:
            return 'username existed'
        else:
            user=User(username=username,password=password,nickname=nickname)
            db.seesion.add(user)#数据库操作
            db.seesion.commit()
            return redirect(url_for('login'))


@app.route('/login/',methods=['GET','POST'])
def login():
    if request.method=='GET':
        return render_template('login.html')
    else:
        username2=request.form.get('username')
        password2=request.form.get('password')
        user = User.query.filter(User.username == username2,User.password==password2).first()
        if user:
            session['user'] == username2
            session.permanent = True
            return render_template(url_for('base'))
        else:
                return u'error username or passwod'
        #     if user.password==password2:
        #         return redirect(url_for('base'))
        #     else:
        #         return u'password error'
        # else:
        #     return u'username is not existed.'

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