Flask-SQLAlchemy

1.安裝

pip install Flask-SQLAlchemy

起步

# 1. 創(chuàng)建表 from flask import Flask from flask_sqlalchemy import SQLAlchemyapp = Flask(__name__) app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql+pymysql://root:123@127.0.0.1/test? app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = Falsecharset=utf8'db = SQLAlchemy(app)class User(db.Model):id = db.Column(db.Integer,primary_key=True)username = db.Column(db.String(32),unique=True,nullable=True)db.create_all() # 2. 添加數(shù)據(jù) db.session.add(User(username='admin'))

加入組件

from flask import Flask# 導(dǎo)入Flask-SQLAlchemy中的SQLAlchemy from flask_sqlalchemy import SQLAlchemy# 實例化SQLAlchemy db = SQLAlchemy() # PS : 實例化SQLAlchemy的代碼必須要在引入藍圖之前from .views.users import userdef create_app():app = Flask(__name__)# 初始化App配置 這個app配置就厲害了,專門針對 SQLAlchemy 進行配置# SQLALCHEMY_DATABASE_URI 配置 SQLAlchemy 的鏈接字符串兒app.config["SQLALCHEMY_DATABASE_URI"] = "mysql+pymysql://root:DragonFire@127.0.0.1:3306/dragon?charset=utf8"# SQLALCHEMY_POOL_SIZE 配置 SQLAlchemy 的連接池大小app.config["SQLALCHEMY_POOL_SIZE"] = 5# SQLALCHEMY_POOL_TIMEOUT 配置 SQLAlchemy 的連接超時時間app.config["SQLALCHEMY_POOL_TIMEOUT"] = 15app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False# 初始化SQLAlchemy , 本質(zhì)就是將以上的配置讀取出來db.init_app(app)app.register_blueprint(user)return app

2.創(chuàng)建表

from MyApp import dbBase = db.Model # from sqlalchemy.ext.declarative import declarative_base # Base = declarative_base() # 每一次我們在創(chuàng)建數(shù)據(jù)表的時候都要做這樣一件事 # 然而Flask-SQLAlchemy已經(jīng)為我們把 Base 封裝好了# 建立User數(shù)據(jù)表 class Users(Base): # Base實際上就是 db.Model__tablename__ = "users"__table_args__ = {"useexisting": True}# 在SQLAlchemy 中我們是導(dǎo)入了Column和數(shù)據(jù)類型 Integer 在這里# 就和db.Model一樣,已經(jīng)封裝好了id = db.Column(db.Integer,primary_key=True)username = db.Column(db.String(32))password = db.Column(db.String(32))if __name__ == '__main__':from MyApp import create_appapp = create_app()# 這里你要回顧一下Flask應(yīng)該上下文管理了# 離線腳本:with app.app_context():db.drop_all()db.create_all()

登錄視圖函數(shù)的應(yīng)用

from flask import Blueprint, request, render_templateuser = Blueprint("user", __name__)from MyApp.models import Users from MyApp import db@user.route("/login",methods=["POST","GET"]) def user_login():if request.method == "POST":username = request.form.get("username")password = request.form.get("password")# from sqlalchemy.orm import sessionmaker# Session = sessionmaker(engine)# db_sesson = Session()# 現(xiàn)在不用了,因為 Flask-SQLAlchemy 也已經(jīng)為我們做好會話打開的工作db.session.add(Users(username=username,password=password))db.session.commit()# 然后再查詢user_info = Users.query.filter(Users.username == username and User.password == password).first()print(user_info.username)if user_info:return f"登錄成功{user_info.username}"return render_template("login.html")

轉(zhuǎn)載于:https://www.cnblogs.com/robertx/p/11123356.html

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