Python Flask RESTPlus：如何在嵌套API模型中获得查询sqlite数据库的结果？

我正在用Flask RESTPlus编写一个api，并希望使用sqlite数据库 首先，我的当前代码：

API模型

lightstate = api.model('LightState', {
    'red': fields.Integer(description='red part of the rgb light'),
    'green': fields.Integer(description='green part of the rgb light'),
    'blue': fields.Integer(description='blue part of the rgb light'),
    'bri': fields.Integer(description='brightness of the light')    
})
lights = api.model('Lights', {
    'id': fields.Integer(readOnly=True, description='The database id of the light'),
    'name': fields.String(required=True, description='light name'),
    'state': fields.Nested(lightstate)
})

数据库模型

from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()

class Lights(db.Model):
    __bind_key__ = 'lights'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(255))
    red = db.Column(db.Integer)
    green = db.Column(db.Integer)
    blue = db.Column(db.Integer)
    bri = db.Column(db.Integer)

    def __init__(self, name, red, green, blue, bri):
        self.name = name
        self.red = red
        self.green = green
        self.blue = blue
        self.bri = bri

lights = api.model('Lights', {
    'id': fields.Integer(readOnly=True, description='The database id of the light'),
    'name': fields.String(required=True, description='light name'),
    'red': fields.Integer(description='red part of the rgb light'),
    'green': fields.Integer(description='green part of the rgb light'),
    'blue': fields.Integer(description='blue part of the rgb light'),
    'bri': fields.Integer(description='brightness of the light')
})

创建数据库条目

def create_light(data):
    name = data.get('name')
    state = data.get('state')
    red = state['red']
    green = state['green']
    blue = state['blue']
    bri = state['bri']
    entry = Lights(name, red, green, blue, bri)
    db.add(entry)

请求处理程序

@namespace.route('/')
class Light(Resource):
    @api.marshal_with(lights)
    def get(self):
        lights_data = Lights.query.all()
        return lights_data

    @api.expect(lights)
    def post(self):
        create_light(request.json)
        return None, 200

如您所见，我想在数据库中存储名称、rbg值和灯光亮度。使用post请求编写数据库效果很好。 但是get请求的结果如下所示：

[
  {
    "id": 1,
    "name": "garden",
    "state": {
      "red": null,
      "green": null,
      "blue": null,
      "bri": null
    }
  },
  {
    "id": 2,
    "name": "pool",
    "state": {
      "red": null,
      "green": null,
      "blue": null,
      "bri": null
    }
  }
]

如您所见，灯光值为空。我知道，我的问题与API模型定义中的嵌套字段有关，因为当我将所有部分放在一个模型中时，它就起作用了

更改了API型号

from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()

class Lights(db.Model):
    __bind_key__ = 'lights'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(255))
    red = db.Column(db.Integer)
    green = db.Column(db.Integer)
    blue = db.Column(db.Integer)
    bri = db.Column(db.Integer)

    def __init__(self, name, red, green, blue, bri):
        self.name = name
        self.red = red
        self.green = green
        self.blue = blue
        self.bri = bri

lights = api.model('Lights', {
    'id': fields.Integer(readOnly=True, description='The database id of the light'),
    'name': fields.String(required=True, description='light name'),
    'red': fields.Integer(description='red part of the rgb light'),
    'green': fields.Integer(description='green part of the rgb light'),
    'blue': fields.Integer(description='blue part of the rgb light'),
    'bri': fields.Integer(description='brightness of the light')
})

输出获取请求

[
  {
    "id": 1,
    "name": "garden",
    "red": 50,
    "green": 205,
    "blue": 50,
    "bri": 84
  },
  {
    "id": 2,
    "name": "pool",
    "red": 255,
    "green": 0,
    "blue": 255,
    "bri": 96
  }
]

---

如何在“状态”键中从数据库中获取值？

您是否检查了数据库中是否设置了这些值？换句话说，当您提交post请求后运行

SELECT*FROM Lights

时，您的DB会返回什么？这些值都在DB中设置。请参阅我最后一篇“代码”帖子。这不是问题。您是否检查了数据库中是否设置了这些值？换句话说，当您提交post请求后运行

SELECT*FROM Lights

时，您的DB会返回什么？这些值都在DB中设置。请参阅我最后一篇“代码”帖子。这不是问题。