EmbeddedDocumentField and ReferenceField in mongoengine

Question

我有一些非常简单的代码：

class User(db.Document):
   username = db.StringField(max_length=25)
   userid = db.StringField(max_length=25)
   password = db.StringField(max_length=25)
   def __repr__(self):
    return '<User %r>' % (self.username)

class DeviceDetails(db.Document):
    profile = ReferenceField(User)
    enduser = db.StringField(max_length=30, required = True)
    model = db.StringField(max_length=25,required = True)
    conversation = db.ListField(db.EmbeddedDocumentField('Conversation'))
   def __repr__(self):
       return self.enduser
class Conversation(db.EmbeddedDocument):
    message = db.StringField(max_length=250)

每个用户都会有一些设备详细信息以及链接到每个设备详细信息的一些对话。对话正在附加到此处提到的每个devicedetails：embeddeddocumentfield和MongoEngine的Reference Field之间有什么区别正常工作。

现在，我希望将用户与DevicedEtails关联。我尝试添加上面"链接"中提到的代码。但是有一个错误：

>>> from feed.models import *
>>> d = DeviceDetails(
... profile = 'aryan',
... enduser = 'two',
... model = 'nokia'
... )
Traceback (most recent call last):
File "<console>", line 8, in <module>
File "/home/anurag/virtual/vir/lib/python2.7/site-packages/mongoengine                
/base/document.py", line 85, in __init__
value = field.to_python(value)
File "/home/anurag/virtual/vir/lib/python2.7/site-packages/mongoengine/fields.py",   
line 937, in to_python
value = DBRef(collection, self.document_type.id.to_python(value))
File "/home/anurag/virtual/vir/lib/python2.7/site-packages/mongoengine
/base/fields.py", line 392, in to_python
value = ObjectId(value)
File "/home/anurag/virtual/vir/lib/python2.7/site-packages/bson/objectid.py", line 90,
in __init__
self.__validate(oid)
File "/home/anurag/virtual/vir/lib/python2.7/site-packages/bson/objectid.py", line 
194, in __validate
raise InvalidId("%s is not a valid ObjectId" % oid)
InvalidId: aryan is not a valid ObjectId

我在用户模型中有一些用户：

>>> User.objects.all()
[<User u'anurag'>, <User u'aryan'>]

谁能告诉我我在这里做错了什么？

Answer 1

根据您的架构Profile是一个参考字段，这意味着它将存储其引用的对象的ID。

您应该将其设置为用户Aryan的id（或仅将其设置为Aryan用户对象），例如：

aryan = User.objects(name="aryan").first()
device = DeviceDetails(profile=aryan, enduser='two', model='nokia').save()