我在SO上看到了一些类似的问题,但似乎没有人回答我的特殊问题。我是Django的新手,并在this page的指导下指导我自己使用自然键加载灯具。然而,我得到反序列化错误,因为Django想要一个外键的整数,并且似乎无法将我的自然键映射到整数主键,如说明中所述。具体来说,我的相关模型代码是:
class GraphTypeManager(models.Manager):
def get_by_natural_key(self, type):
return self.get(type=type)
class GraphType(models.Model):
type = models.CharField(max_length=100, unique=True)
class GraphManager(models.Manager):
def get_by_natural_key(self, name):
return self.get(name=name)
class Graph(models.Model):
name = models.CharField(max_length=200, unique=True)
type = models.ForeignKey(GraphType)
class LineManager(models.Manager):
def get_by_natural_key(self, name):
return self.get(name=name)
class Line(models.Model):
name = models.CharField(max_length=200, unique=True)
class GraphToLineManager(models.Manager):
def get_by_natural_key(self, line, graph):
return self.get(line=line,graph=graph)
class GraphToLine(models.Model):
line = models.ForeignKey(Line)
graph = models.ForeignKey(Graph)
class Meta:
unique_together = (('line', "graph"),)
我的YAML夹具是:
- model: graphs_container.GraphType
pk: null
fields:
type: TimeSeries
- model: graphs_container.Graph
pk: null
fields:
name: LikesOverTime
type: [TimeSeries]
- model: graphs_container.Graph
pk: null
fields:
name: UsersOverTime
type: [TimeSeries]
- model: graphs_container.Line
pk: null
fields:
name: NumUsers
- model: graphs_container.Line
pk: null
fields:
name: NumLikes
但是在尝试运行python manage.py loaddata sample_data.yaml
时,我收到以下错误:
DeserializationError: [u"'['TimeSeries']' value must be an integer."]
我做错了什么?
答案 0 :(得分:5)
你需要
natural_key
方法get_by_natural_key
方法objects=GraphManager()
)在使用您的代码后,我让它成功了:
class GraphTypeManager(models.Manager):
def get_by_natural_key(self, type):
return self.get(type=type)
class GraphType(models.Model):
type = models.CharField(max_length=100, unique=True)
objects = GraphTypeManager()
def natural_key(self):
return (self.type,) # must return a tuple
class GraphManager(models.Manager):
def get_by_natural_key(self, name):
return self.get(name=name)
class Graph(models.Model):
name = models.CharField(max_length=200, unique=True)
type = models.ForeignKey(GraphType)
objects = GraphManager()
转储数据:
$ bin/django dumpdata index --indent=4 --natural > project/apps/fixtures_dev/initial_data.json
[
{
"pk": 1,
"model": "index.graphtype",
"fields": {
"type": "asotuh"
}
},
{
"pk": 1,
"model": "index.graph",
"fields": {
"type": [
"asotuh"
],
"name": "saoneuht"
}
}
]
bin/django loaddata project/apps/fixtures_dev/initial_data.json
Installed 2 object(s) from 1 fixture(s)