我很抱歉在先进的任何缺乏解释,以及这篇文章的长度。我认为这个问题比我想象的要简单得多。我有两个模型利用一对多关系。对于InsightModel,我的json()方法显示了以下内容:
{
name: "insightname",
start: 1,
end: 3,
podcast_id: 1,
podcast: {
name: "podcast1",
wave_data: 1,
length: 2,
host: "Hosterman",
category: "entertain",
pub_date: "11/1",
cover_art_url: "google.com"
}
}
对于我的PodcastModel,json()方法显示以下内容:
{
name: "podcast1",
wave_data: 1,
length: 2,
host: "Hosterman",
category: "entertain",
pub_date: "11/1",
cover_art_url: "google.com",
insights: [
{
name: "insightname",
start: 1,
end: 3,
podcast_id: 1
}
]
}
这是我所需要的,但为了让它工作,我必须为每个类创建两个json()方法,以避免PodcastModel中出现如下递归:
{
name: "podcast1",
wave_data: 1,
length: 2,
host: "Hosterman",
category: "entertain",
pub_date: "11/1",
cover_art_url: "google.com",
insights: [
{
name: "insightname",
start: 1,
end: 3,
podcast_id: 1,
podcast: {
name: "podcast1",
wave_data: 1,
length: 2,
host: "Hosterman",
category: "entertain",
pub_date: "11/1",
cover_art_url: "google.com",
}
}
]
}
我的播客模型代码是:
from db import db
from datetime import datetime
class PodcastModel(db.Model):
__tablename__ = 'podcasts'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(100))
wave_data = db.Column(db.Float(precision=2))
length = db.Column(db.Float(precision=2))
host = db.Column(db.String(80))
category = db.Column(db.String(80))
pub_date = db.Column(db.String(50))
cover_art_url = db.Column(db.String(200))
insights = db.relationship('InsightModel', backref='podcast', lazy='dynamic')
def __init__(self, name, wave_data, length, host, category, pub_date, cover_art_url):
self.name = name
self.wave_data = wave_data
self.length = length
self.host = host
self.category = category
self.pub_date = pub_date
self.cover_art_url = cover_art_url
def json(self):
return {'name': self.name, 'wave_data': self.wave_data, 'length': self.length, 'host': self.host, 'category': self.category, 'pub_date': self.pub_date, 'cover_art_url': self.cover_art_url, 'insights': [insight.json_no_podcast() for insight in self.insights.all()]}
def json_no_insight(self):
return {'name': self.name, 'wave_data': self.wave_data, 'length': self.length, 'host': self.host, 'category': self.category, 'pub_date': self.pub_date, 'cover_art_url': self.cover_art_url}
@classmethod
def find_by_name(cls, name):
# Select * FROM items WHERE name=name LIMIT 1
return cls.query.filter_by(name=name).first()
@classmethod
def find_by_id(cls, _id):
return cls.query.filter_by(id=_id)
InsightModel如下所示:
from db import db
from models.podcast import PodcastModel
class InsightModel(db.Model):
__tablename__ = 'insights'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(100))
start = db.Column(db.Float(precision=2))
end = db.Column(db.Float(precision=2))
podcast_id = db.Column(db.Integer, db.ForeignKey('podcasts.id'))
#podcast = db.relationship('PodcastModel')
def __init__(self, name, start, end, podcast_id):
self.name = name
self.start = start
self.end = end
self.podcast_id = podcast_id
def json(self):
podcast = PodcastModel.find_by_id(self.podcast_id).first().json_no_insight()
return {'name': self.name, 'start': self.start, 'end': self.end,
'podcast_id': self.podcast_id, 'podcast': podcast}
def json_no_podcast(self):
return {'name': self.name, 'start': self.start, 'end': self.end,
'podcast_id': self.podcast_id}
@classmethod
def find_by_name(cls, name):
# Select * FROM items WHERE name=name LIMIT 1
return cls.query.filter_by(name=name).first()
如您所见,我添加了json \u no \u insights()和json \u no \u podcast()方法来防止发生递归。然而,我确信阅读这段代码已经给了你一种胃部凹陷的感觉,我迫切需要一个更好的方法来编写它。非常感谢您的任何见解,再次,我为这篇文章的篇幅或任何缺乏解释道歉。你知道吗
让你的生活更轻松-使用棉花糖。你知道吗
然后简单地像这样转储数据:
注意在
PodcastSchema
中缺少podcast
字段-这将导致(不调整)无限递归。如果需要该字段,可以尝试以下操作:相关问题 更多 >
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