时，你也可以使用 --user 选项进行用户安装（即 pip install --user pipenv ）。用户安装可以避免破坏全局的包，而且可以避 免对不可信的包使用 sudo pip 导致的潜在安全问题。详情见 Pipenv 文档安装 章节。 第 1 章：准备工作 13 第 2 章：Hello, Flask! 追溯到最初，Flask 诞生于 Armin Ronacher 在 2010 app.config['SECRET_KEY'] = 'dev' # 等同于 app.secret_key = 'dev' 第 7 章：表单 64 提示 这个密钥的值在开发时可以随便设置。基于安全的考虑，在部署时应该设置为 随机字符，且不应该明文写在代码里， 在部署章节会详细介绍。 下面在基模板（base.html）里使用 get_flashed_messages() 函数获取提示消 commit() # 提交数据库会话 flash('Item deleted.') return redirect(url_for('index')) # 重定向回主页 为了安全的考虑，我们一般会使用 POST 请求来提交删除请求，也就是使用表单来 实现（而不是创建删除链接）： index.html：删除电影条目表单 第 7 章：表单 69

1": "123 fake street", "line 2": null, "state": "NY", "zip ˓→": "10468", "city": "New York"}, "name": "bob", "shipping_address": {"line 1": "555 ˓→nowhere", "line 2": null, "state": "NY", "zip": "10468" (bool) – If enabled, trims whitespace around the argument. • nullable (bool) – If enabled, allows null value in argument. __init__(name, default=None, dest=None, required=False, ignore=False, type=null=False, **kwargs) Allows you to nest one set of fields inside another. See Advanced : Nested Field for more information Parameters • nested (dict) – The dictionary to nest • allow_null (bool)

1": "123 fake street", "line 2": null, "state": "NY", "zip": "10468", "city": "New York"}, "name": "bob", "shipping_address": {"line 1": "555 nowhere", "line 2": null, "state": "NY", "zip": "10468", trim (bool) – If enabled, trims whitespace around the argument. nullable (bool) – If enabled, allows null value in argument. __init__(name, default=None, dest=None, required=False, ignore=False, type=null=False, **kwargs) Allows you to nest one set of fields inside another. See Advanced : Nested Field for more information Parameters: nested (dict) – The dictionary to nest allow_null (bool)

1": "123 fake street", "line 2": null, "state": "NY", "zip ˓→": "10468", "city": "New York"}, "name": "bob", "shipping_address": {"line 1": "555 ˓→nowhere", "line 2": null, "state": "NY", "zip": "10468" (bool) – If enabled, trims whitespace around the argument. • nullable (bool) – If enabled, allows null value in argument. __init__(name, default=None, dest=None, required=False, ignore=False, type=null=False, **kwargs) Allows you to nest one set of fields inside another. See Advanced : Nested Field for more information Parameters • nested (dict) – The dictionary to nest • allow_null (bool)

1": "123 fake street", "line 2": null, "state": "NY", "zip ˓→": "10468", "city": "New York"}, "name": "bob", "shipping_address": {"line 1": "555 ˓→nowhere", "line 2": null, "state": "NY", "zip": "10468" (bool) – If enabled, trims whitespace around the argument. • nullable (bool) – If enabled, allows null value in argument. __init__(name, default=None, dest=None, required=False, ignore=False, type=null=False, **kwargs) Allows you to nest one set of fields inside another. See Advanced : Nested Field for more information Parameters • nested (dict) – The dictionary to nest • allow_null (bool)

1": "123 fake street", "line 2": null, "state": "NY", "zip": "10468", "city": "New York"}, "name": "bob", "shipping_address": {"line 1": "555 nowhere", "line 2": null, "state": "NY", "zip": "10468", argument. nullable (bool [https://docs.python.org/3/library/functions.html#bool]) – If enabled, allows null value in argument. Parameters: Parameters: Parameters: Raises: __init__(name, default=None, dest=None def format(self, value): return unicode(value).title() class fields.Nested(nested, allow_null=False, **kwargs) Allows you to nest one set of fields inside another. See Advanced : Nested Field

1": "123 fake street", "line 2": null, "state": "NY", "zip": "10468", "city": "New York"}, "name": "bob", "shipping_address": {"line 1": "555 nowhere", "line 2": null, "state": "NY", "zip": "10468", argument. nullable (bool [https://docs.python.org/3/library/functions.html#bool]) – If enabled, allows null value in argument. Parameters: Parameters: Parameters: Raises: __init__(name, default=None, dest=None def format(self, value): return unicode(value).title() class fields.Nested(nested, allow_null=False, **kwargs) Allows you to nest one set of fields inside another. See Advanced : Nested Field

NOT NULL, password TEXT NOT NULL ); CREATE TABLE post ( id INTEGER PRIMARY KEY AUTOINCREMENT, author_id INTEGER NOT NULL, created TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP, title TEXT NOT NULL, body body TEXT NOT NULL, FOREIGN KEY (author_id) REFERENCES user (id) ); Add the Python functions that will run these SQL commands to the db.py file: Listing 6: flaskr/db.py def init_db(): db = get_db() through subclassing to change the default behavior of OPTIONS responses. New in version 0.7. make_null_session() Creates a new instance of a missing session. Instead of overriding this method we recommend

username TEXT UNIQUE NOT NULL, password TEXT NOT NULL ); CREATE TABLE post ( id INTEGER PRIMARY KEY AUTOINCREMENT, author_id INTEGER NOT NULL, created TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP CURRENT_TIMESTAMP, title TEXT NOT NULL, body TEXT NOT NULL, FOREIGN KEY (author_id) REFERENCES user (id) ); Add the Python functions that will run these SQL commands to the db.py file: flaskr/db.py def init_db(): changed through subclassing to change the default behavior of OPTIONS responses. Changelog make_null_session() Creates a new instance of a missing session. Instead of overriding this method we recommend

1": "123 fake street", "line 2": null, "state": "NY", "zip": "10468", "city": "New York"}, "name": "bob", "shipping_address": {"line 1": "555 nowhere", "line 2": null, "state": "NY", "zip": "10468",