Flask-Migrate

一、安装 Flask-Script 和  Flask-Migrate

新建一个FLask 项目
目录如下：

下面是主要py文件的内容
__init__.py

from flask_sqlalchemy import SQLAlchemy
from flask import Flask
from My_app.views.user import user
from My_app.views.uerlist import userlist

db = SQLAlchemy()


def create_app():
    app = Flask(__name__)
    app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql+pymysql://root:@127.0.0.1:3306/bms?charset=utf8'

    # SQLALCHEMY_POOL_SIZE 配置 SQLAlchemy 的连接池大小
    app.config["SQLALCHEMY_POOL_SIZE"] = 5

    # SQLALCHEMY_POOL_TIMEOUT 配置 SQLAlchemy 的连接超时时间
    app.config["SQLALCHEMY_POOL_TIMEOUT"] = 15
    app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False
    
    db.init_app(app)
    app.register_blueprint(user)
    app.register_blueprint(userlist)

    return app

models.py

from My_app import db


class User(db.Model):
    __tablename__ = "user"
    __table_args__ = {"useexisting": True}

    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(32))


if __name__ == '__main__':
    from My_app import create_app
    my_app = create_app()

    db.drop_all(app=my_app)
    db.create_all(app=my_app)

views文件下主要是蓝图，在__init__.py下导入并注册

二、将  Flask-Script 加入到Flask项目中

import My_app
from flask_script import Manager
from flask_migrate import Migrate, MigrateCommand
from My_app import db

my_app = My_app.create_app()
# 让app支持 Manager
manage = Manager(my_app)

# Migrate 既然是数据库迁移,那么就得告诉他数据库在哪里
# 并且告诉他要支持那个app
Migrate(my_app, db)
# 现在就要告诉manager 有新的指令了,这个新指令在MigrateCommand 中存着呢
manage.add_command('databases', MigrateCommand)


@manage.command
def runflask():
    my_app.run()
    return 'success'


@manage.option('-n', '--name', dest='name')
@manage.option('-s', '--say', dest='say')
def run_flask(name, say):
    a = input("是否启动flask")
    if a == 'y':
        if not name:
            name = '127.0.2.1'
        if not say:
            say = 5000
        my_app.run(name, int(say))
    else:
        return f"{name}真{say}"


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

三、运行 python manage.py databases init 

之后会在目录下看到：