flaskmigrate的使用

Z时代
2024-01-10
分类：综合

manager.py代码如下:

from flask_script import Manager, Shell, Server
from flask_migrate import Migrate, MigrateCommand
from app.ext import db
from app import create_app
app = create_app()
manager = Manager(app=app)
migrate = Migrate(app, db)
def make_shell_context():
	return dict(app=app)
manager.add_command("shell", Shell(make_context=make_shell_context))
manager.add_command("run_dev", Server(use_debugger=True, use_reloader=True))
manager.add_command("runserver", Server())
manager.add_command("db", MigrateCommand)
@manager.command
def deploy():
	"""run deployment tasks"""
	pass
if __name__ == "__main__":
	manager.run(default_command="runserver")

执行python manager.py db 查看参数说明

@MacBook-Pro-2 Garen % python manager.py db usage: Perform database migrations Perform database migrations positional arguments: {init,revision,migrate,edit,merge,upgrade,downgrade,show,history,heads,branches,current,stamp} init Creates a new migration repository revision Create a new revision file. migrate Alias for "revision --autogenerate" edit Edit current revision. merge Merge two revisions together. Creates a new migration file upgrade Upgrade to a later version downgrade Revert to a previous version show Show the revision denoted by the given symbol. history List changeset scripts in chronological order. heads Show current available heads in the script directory branches Show current branch points current Display the current revision for each database. stamp "stamp" the revision table with the given revision; don"t run any migrations

创建数据库操作

初始化数据库

init命令会创建一个新的版本仓库,并且会生成migrations文件夹.这点类似django.

(Garen) zhouwanghua@MacBook-Pro-2 Garen % python manager.py db init Creating directory /Users/zhouwanghua/Code/Garen/migrations ... done Creating directory /Users/zhouwanghua/Code/Garen/migrations/versions ... done Generating /Users/zhouwanghua/Code/Garen/migrations/script.py.mako ... done Generating /Users/zhouwanghua/Code/Garen/migrations/env.py ... done Generating /Users/zhouwanghua/Code/Garen/migrations/README ... done Generating /Users/zhouwanghua/Code/Garen/migrations/alembic.ini ... done Please edit configuration/connection/logging settings in "/Users/zhouwanghua/Code/Garen/migrations/alembic.ini" before proceeding.

创建version表

执行upgrade之后会在数据中创建一个alembic_version表

(Garen) zhouwanghua@MacBook-Pro-2 Garen % python manager.py db upgrade
INFO  [alembic.runtime.migration] Context impl MySQLImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.

生成models对象的迁移脚本

如果有新的表或字段改动都需要使用这个命令,类似django的makemigrations

(Garen) zhouwanghua@MacBook-Pro-2 Garen % python manager.py db migrate
INFO  [alembic.runtime.migration] Context impl MySQLImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
INFO  [alembic.autogenerate.compare] Detected added table "reply"
  Generating /Users/zhouwanghua/Code/Garen/migrations/versions/d5e95964b986_.py ...  done

在执行迁移命令upgrade

执行迁移脚本,创建/维护表

(Garen) zhouwanghua@MacBook-Pro-2 Garen % python manager.py db upgrade
INFO  [alembic.runtime.migration] Context impl MySQLImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
INFO  [alembic.runtime.migration] Running upgrade  -> d5e95964b986, empty message