使用棉花糖对嵌套字段进行缩放

Question

我有两个类似的数据库模型

class Setting(db.Model):
id = db.Column(db.Integer, id=True)
container_id = ST_db.Column(ST_db.Integer, db.ForeignKey('settings_container.id'))
setting_name = ST_db.Column(ST_db.String(50))
setting_value = ST_db.Column(ST_db.String(50))
class SettingsContainer(db.Model):
id = db.Column(db.Integer, id=True)
settings = db.relationship('Settings', backref='container', cascade='all, delete')

当我使用以下模式序列化模型时

class Setting(ma.Schema):
class Meta:
fields = (
'setting_name',
'setting_value',
)
class SettingsContainer(ma.Schema):
settings = ST_ma.Nested(Setting, many=True)
class Meta:
fields = (
'id',
'settings'
)

我得到的是

[
{
"id": 1
"settings": [
{
"setting_name": 'name1',
"setting_value": 'value1'
},
{
"setting_name": 'name2',
"setting_value": 'value2'
},
}
"id": 2
"settings": [
{
"setting_name": 'name3',
"setting_value": 'value3'
},
{
"setting_name": 'name4',
"setting_value": 'value4'
},
]

但我想得到格式的数据

[
{
"id": 1
"settings": [['name1', 'value1'], ['name2', 'value2']]
}
{
"id": 2
"settings": [['name3', 'value3'], ['name4', 'value4']]
}
]

我想提取Nested字段，我不知道如何使用ma.Function方法来提取，提前感谢大家。

Answer 1

好的，所以我找到了答案，我要做的是将ma.Function与ma.Pluck一起使用

合适的序列化程序是。

class Setting(ma.Schema):
complete_setting = ma.Function(lambda setting:(
setting.setting_name,
setting.setting_value,
)) 
class SettingsContainer(ma.Schema):
settings = ma.List(ma.Pluck(Setting, 'complete_setting'))
class Meta:
fields = (
'id',
'settings'
)