我正在关注flask mega教程，我目前正在尝试运行“flask db migrate”命令，但我遇到了一些错误，我不确定我是否愚蠢地看到它，但它不是指对我的任何文件真的。
Traceback (most recent call last):
File "/home/moe/cryptowatch/venv/bin/flask", line 8, in <module>
sys.exit(main())
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask/cli.py", line 967, in main
cli.main(args=sys.argv[1:], prog_name="python -m flask" if as_module else None)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask/cli.py", line 586, in main
return super(FlaskGroup, self).main(*args, **kwargs)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/click/core.py", line 782, in main
rv = self.invoke(ctx)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/click/core.py", line 1259, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/click/core.py", line 1259, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/click/core.py", line 1066, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/click/core.py", line 610, in invoke
return callback(*args, **kwargs)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/click/decorators.py", line 21, in new_func
return f(get_current_context(), *args, **kwargs)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask/cli.py", line 426, in decorator
return __ctx.invoke(f, *args, **kwargs)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/click/core.py", line 610, in invoke
return callback(*args, **kwargs)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask_migrate/cli.py", line 91, in migrate
_migrate(directory, message, sql, head, splice, branch_label, version_path,
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask_migrate/__init__.py", line 96, in wrapped
f(*args, **kwargs)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask_migrate/__init__.py", line 210, in migrate
command.revision(config, message, autogenerate=True, sql=sql,
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/alembic/command.py", line 212, in revision
script_directory.run_env()
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/alembic/script/base.py", line 490, in run_env
util.load_python_file(self.dir, "env.py")
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/alembic/util/pyfiles.py", line 97, in load_python_file
module = load_module_py(module_id, path)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/alembic/util/compat.py", line 182, in load_module_py
spec.loader.exec_module(module)
File "<frozen importlib._bootstrap_external>", line 783, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "migrations/env.py", line 25, in <module>
str(current_app.extensions['migrate'].db.engine.url).replace('%', '%%'))
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask_sqlalchemy/__init__.py", line 943, in engine
return self.get_engine()
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask_sqlalchemy/__init__.py", line 962, in get_engine
return connector.get_engine()
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask_sqlalchemy/__init__.py", line 555, in get_engine
options = self.get_options(sa_url, echo)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask_sqlalchemy/__init__.py", line 570, in get_options
self._sa.apply_driver_hacks(self._app, sa_url, options)
File "/home/moe/cryptowatch/venv/lib/python3.8/site-packages/flask_sqlalchemy/__init__.py", line 914, in apply_driver_hacks
sa_url.database = os.path.join(app.root_path, sa_url.database)
AttributeError: can't set attribute
答案 0 :(得分：-1)
有关详细信息，请参阅 this thread。如果您有 1.4.0 版的 sqlalchemy，请卸载它并安装以前的版本。
如果您的代码是正确的，那么应该可以解决问题。