如何使用flask和jsonify在json响应中添加嵌套数组和对象
我目前正在遵循这一点来启动并运行一个API(下面是我的代码) 我希望最后得到一个嵌套数组,如何使用flask和jsonify在json响应中添加嵌套数组和对象,json,flask,python-3.8,Json,Flask,Python 3.8,我目前正在遵循这一点来启动并运行一个API(下面是我的代码) 我希望最后得到一个嵌套数组,标记,和一个嵌套对象,位置,如下所示 [{ "description": "TEST DESCRIPTION", "id": 1, "title": "TEST TITLE", "date": "2020-09-02", &quo
标记
,和一个嵌套对象,位置
,如下所示
[{
"description": "TEST DESCRIPTION",
"id": 1,
"title": "TEST TITLE",
"date": "2020-09-02",
"scheduled":"true",
"favourite":"true",
"tags": ["celebration", "national holiday"],
"location": {
"state": {
"name": "new zealand",
"affiliation": ["United Nations"]
},
"province": "",
"urbanisation": "Wellington"
}
},
{
"description": "LONG DESCRIPTION",
"id": 2,
"title": "SECOND ENTRY",
"date": "2020-09-03",
"scheduled":"false",
"favourite":"false",
"tags": ["election", "national holiday"],
"location": {
"state": {
"name": "Brazil",
"affiliation": [""]
},
"province": "",
"urbanisation": ""
}
}]
这样的事情可能吗?我是否需要重新考虑API,使端点覆盖每个嵌套对象
api.add_resource(Events, '/events')
api.add_resource(tags, '/events/tag')
api.add_resource(location, '/events/location')
或者,我是否将字典嵌套在中。是的,它可能并且完全有效。但我不会直接查询数据库。我会使用ORM,因为烧瓶使用可以使用扩展。序列化可以通过使用 使用SQLAlchemy创建模型:
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:////tmp/test.db'
db = SQLAlchemy(app)
class EventModel(db.Model):
__tablename__ = "event"
id = db.Column(db.Integer, primary_key=True)
title = db.Column(db.String, nullable=True)
class LocationModel(db.Model):
__tablename__ = "location"
id = db.Column(db.Integer, primary_key=True)
province = db.Column(db.String, nullable=True)
event_id = db.Column(db.Integer, db.ForeignKey("event.id", ondelete="CASCADE"), nullable=False)
event = db.relationship("EventModel", backref=db.backref("locations", lazy=True))
然后需要序列化程序类(使用flask marshmallow)来处理序列化:
from marshmallow_sqlalchemy import SQLAlchemyAutoSchema, fields
from marshmallow_sqlalchemy import auto_field
class LocationSchema(SQLAlchemyAutoSchema):
class Meta:
model = LocationModel
load_instance = True
include_fk = False
id = auto_field(load_only=True)
class EventSchema(SQLAlchemyAutoSchema):
class Meta:
model = EventModel
load_instance = True
include_fk = False
id = auto_field(load_only=True)
locations = fields.Nested(LocationSchema, many=True)
最后,您可以序列化为json,如下所示:
db.drop_all()
db.create_all()
event = EventModel(title="Summer Show")
db.session.add(event)
db.session.commit()
location1 = LocationModel(province="Upper Austria", event_id=event.id)
db.session.add(location1)
location2 = LocationModel(province="Tirol", event_id=event.id)
db.session.add(location2)
db.session.commit()
schema = EventSchema()
result = db.session.query(EventModel).all()
print(schema.dump(result, many=True))
可以找到完整的教程。太好了。我会很快把这件事做完,然后再报告。谢谢。如果我读对了,位置表将事件id作为外键。如果事件和位置是多对一呢?外键站点是否同时在表和模型中包含事件,并以相反的方式表示关系?我现在使代码可以运行。只需将其复制到脚本中,并使用python>=3.6进行尝试。事件和位置已经是多对一了:一个事件可以有多个位置。因此,外键位于位置模型中。此外,还需要一个关系字段来连接两个模型。请参阅此处了解更多详细信息:这是非常清晰的文档,我保留它。对于我的模型,任何单个事件只能有一个位置,任何单个位置都可以有多个事件。。我如何为此建立关系?
db.drop_all()
db.create_all()
event = EventModel(title="Summer Show")
db.session.add(event)
db.session.commit()
location1 = LocationModel(province="Upper Austria", event_id=event.id)
db.session.add(location1)
location2 = LocationModel(province="Tirol", event_id=event.id)
db.session.add(location2)
db.session.commit()
schema = EventSchema()
result = db.session.query(EventModel).all()
print(schema.dump(result, many=True))