如何修复django模型实例

错误消息 ValueError:无法分配“”：“Diagnostics.owner”必须是“Patient”实例

当我尝试创建新卡或诊断时，会出现上述错误。 卡片和诊断意味着是患者的一个实例，就像患者拥有卡片和诊断的方式一样。patient类有一个引用用户的foregin键。 这是密码

视图.py

    from django.shortcuts import render
from rest_framework.generics import ListCreateAPIView, RetrieveUpdateDestroyAPIView
from .serializers import PatientsSerializer, PatientsCardSerializer, PatientsDiagnosesSerializer
from .models import Patient, Card, Diagnoses
from rest_framework import permissions
from .permissions import IsOwner


# Patient Views
class PatientListAPIView(ListCreateAPIView):
    serializer_class = PatientsSerializer
    queryset = Patient.objects.all()
    permission_classes = (permissions.IsAuthenticated, IsOwner,) 
    def perform_create(self, serializer):
        return serializer.save(owner=self.request.user)
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)

class PatientDetailAPIView(RetrieveUpdateDestroyAPIView):
    serializer_class = PatientsSerializer
    permission_classes = (permissions.IsAuthenticated, IsOwner,)
    queryset = Patient.objects.all()
    lookup_field = "id"
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)


class PatientCardListAPIView(ListCreateAPIView):
    serializer_class = PatientsCardSerializer
    queryset = Card.objects.all()
    permission_classes = (permissions.IsAuthenticated,) 
    def perform_create(self, serializer):
        return serializer.save(owner=self.request.user)
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)

class PatientCardDetailAPIView(RetrieveUpdateDestroyAPIView):
    serializer_class = PatientsCardSerializer
    permission_classes = (permissions.IsAuthenticated, IsOwner,)
    queryset = Card.objects.all()
    lookup_field = "id"
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)



class PatientDiagnosesListAPIView(ListCreateAPIView):
    serializer_class = PatientsDiagnosesSerializer
    queryset = Diagnoses.objects.all()
    permission_classes = (permissions.IsAuthenticated,) 
    def perform_create(self, serializer):
        return serializer.save(owner=self.request.user)
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)

class PatientDiagnosesDetailAPIView(RetrieveUpdateDestroyAPIView):
    serializer_class = PatientsDiagnosesSerializer
    permission_classes = (permissions.IsAuthenticated, IsOwner,)
    queryset = Diagnoses.objects.all()
    lookup_field = "id"
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)

class Patient(models.Model):
    name = models.CharField(max_length=255, null=True)
    country = models.CharField(max_length=255, null=True)
    state = models.CharField(max_length=255, null=True)
    phone = models.CharField(max_length=255, null=True)
    email = models.CharField(max_length=255, null=True)
    owner = models.ForeignKey(to=User, null=True, on_delete=models.CASCADE)
    def __str__(self):
        return self.name
class Card(models.Model):    
    name = models.CharField(max_length=255, null=True)
    card_number = models.CharField(max_length=255, null=True)    
    owner = models.OneToOneField(Patient, null=True, blank=True, on_delete=models.CASCADE)
    def __str__(self):
        return (self.patient.name)+"'s card"
   
class Diagnoses(models.Model):
    sickness = models.CharField(max_length=255, null=True)
    note = models.TextField(max_length=255, null=True)   
    owner = models.ForeignKey(Patient, null=True, on_delete=models.SET_NULL)
    def __str__(self):
        return (self.patient.name)+"'s diagnoses"

型号.py

    from django.shortcuts import render
from rest_framework.generics import ListCreateAPIView, RetrieveUpdateDestroyAPIView
from .serializers import PatientsSerializer, PatientsCardSerializer, PatientsDiagnosesSerializer
from .models import Patient, Card, Diagnoses
from rest_framework import permissions
from .permissions import IsOwner


# Patient Views
class PatientListAPIView(ListCreateAPIView):
    serializer_class = PatientsSerializer
    queryset = Patient.objects.all()
    permission_classes = (permissions.IsAuthenticated, IsOwner,) 
    def perform_create(self, serializer):
        return serializer.save(owner=self.request.user)
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)

class PatientDetailAPIView(RetrieveUpdateDestroyAPIView):
    serializer_class = PatientsSerializer
    permission_classes = (permissions.IsAuthenticated, IsOwner,)
    queryset = Patient.objects.all()
    lookup_field = "id"
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)


class PatientCardListAPIView(ListCreateAPIView):
    serializer_class = PatientsCardSerializer
    queryset = Card.objects.all()
    permission_classes = (permissions.IsAuthenticated,) 
    def perform_create(self, serializer):
        return serializer.save(owner=self.request.user)
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)

class PatientCardDetailAPIView(RetrieveUpdateDestroyAPIView):
    serializer_class = PatientsCardSerializer
    permission_classes = (permissions.IsAuthenticated, IsOwner,)
    queryset = Card.objects.all()
    lookup_field = "id"
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)



class PatientDiagnosesListAPIView(ListCreateAPIView):
    serializer_class = PatientsDiagnosesSerializer
    queryset = Diagnoses.objects.all()
    permission_classes = (permissions.IsAuthenticated,) 
    def perform_create(self, serializer):
        return serializer.save(owner=self.request.user)
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)

class PatientDiagnosesDetailAPIView(RetrieveUpdateDestroyAPIView):
    serializer_class = PatientsDiagnosesSerializer
    permission_classes = (permissions.IsAuthenticated, IsOwner,)
    queryset = Diagnoses.objects.all()
    lookup_field = "id"
    def get_queryset(self):
        return self.queryset.filter(owner=self.request.user)

class Patient(models.Model):
    name = models.CharField(max_length=255, null=True)
    country = models.CharField(max_length=255, null=True)
    state = models.CharField(max_length=255, null=True)
    phone = models.CharField(max_length=255, null=True)
    email = models.CharField(max_length=255, null=True)
    owner = models.ForeignKey(to=User, null=True, on_delete=models.CASCADE)
    def __str__(self):
        return self.name
class Card(models.Model):    
    name = models.CharField(max_length=255, null=True)
    card_number = models.CharField(max_length=255, null=True)    
    owner = models.OneToOneField(Patient, null=True, blank=True, on_delete=models.CASCADE)
    def __str__(self):
        return (self.patient.name)+"'s card"
   
class Diagnoses(models.Model):
    sickness = models.CharField(max_length=255, null=True)
    note = models.TextField(max_length=255, null=True)   
    owner = models.ForeignKey(Patient, null=True, on_delete=models.SET_NULL)
    def __str__(self):
        return (self.patient.name)+"'s diagnoses"

---

到目前为止，

self.request.user

是一个

user

对象。因此，无法将其保存到API或保存到模型。为清楚起见，它不是患者对象

根据您的情况，我会将

Patient

对象与

User

对象（如果这是单向引用对象）一起排队，并将其放入参数中，然后执行save（）方法

class PatientCardListAPIView（ListCreateAPIView）：
serializer\u class=PatientsCardSerializer
queryset=Card.objects.all（）
权限\类=（permissions.IsAuthenticated，）
def执行_创建（自、序列化程序）：
getPatientFromUser=Patient.objects.get（所有者=self.request.user）
#getPatientFromUser返回'Patient'实例。所以你可以把它绑在“卡片”模型里。
返回serializer.save（所有者=getPatientFromUser）
def get_queryset（自我）：
返回self.queryset.filter（所有者=self.request.user）

注:

这是一个单向参考的解决方案。（

用户

被称为患者）

如果

User

和

Patience

之间存在交叉引用关系（其中User和Patience彼此有外键），则声明您的

用户

模型

该解决方案向用户查询患者。因为用户与该外来对象不兼容

---

向我们展示用于创建实例的代码。模型没有问题。应该是在执行时出现问题。我们添加了创建实例的代码。我编辑了这篇文章并添加了视图。py我有几个问题，1）回溯是否会导致

views.py

？？？2.）此外，

User

不是

Patience

，因此您不能仅仅依赖

User

实例，除非

User

与

Patience

有交叉引用。如果存在交叉引用，我们可以通过将其重定向到该对象来解决它。如果您只有单向引用，我建议将该对象

User

查询到

Patience

。我可以回答，但让我们看看你会怎么做。这是我已经看到的患者模型，我的意思是

返回serializer.save（owner=self.request.user）

<代码>自我请求。用户不是患者对象。它是一个用户对象。因此它会发出错误。我建议将此

用户

对象查询到

患者

对象。为了以防万一，我可能会把这个答案和其他上下文放在一起。对不起，我该如何声明选项2Oh的用户模型，我以为您明确声明了

User

，我想现在您可以选择单向引用。您可以用子类

AbstractBaseUser

或

AbstractUser

声明您的

User

类。但这需要重新声明用户字段。这意味着它将更加可定制，但您必须自己声明字段。有关这些类的更多信息，请查看文档。如果您现在不打算更改

用户

模型，那么我建议使用我从上面提供的单向参考解决方案。（如果这似乎足够，请将其标记为已接受答案）当我提示您在此处给出的第一个选项时，您在/patient/card get（）返回的多个对象返回了一个以上的患者，返回了3！