Question

我有两个模型 Requests和Events，其外键返回User模型。当尝试使用Django Rest Framework发布外键数据时，我收到 null约束错误。似乎django不接受 user_id （requester_id和event_admin_id）引用。在可浏览的API中，外键部分（requester_id和event_id）不存在。它被某些东西隐藏了吗？请注意，event_participant仅由外键组成，但在发布时会显示在可浏览的API中。我不确定会有什么区别

Missing event_admin_id foreignkey field Missing request_admin_id fk field

models.py

from django.db import models
from django.contrib.auth.models import AbstractUser

# Create your models here.
class User(AbstractUser):
    user_job_description = models.CharField(max_length =  200)
    user_profile_pic = models.ImageField(null = True, blank = True)


class Event(models.Model):
    def __str__(self):
         return self.event_name
    event_name = models.CharField(max_length = 100)
    event_location = models.CharField(max_length = 100)
    event_description = models.TextField(max_length = 300)
    admin_user_id = models.ForeignKey(User, related_name = 'event_admin')

class Request(models.Model):
     def __str__(self):
        return self.request_desc
     requester_user_id = models.ForeignKey(User, related_name = 'requests')
     request_desc = models.TextField(max_length = 100)
     fulfiller_user_id = models.IntegerField(null = True, blank = True)
     fulfilled_status = models.BooleanField()


class Event_Participant(models.Model):
    def __str__(self):
        return str(self.event_id)
    user_id = models.ForeignKey(User, related_name = 'event_attendee')
    event_id = models.ForeignKey(Event, related_name = 'event')

serializers.py

from django.contrib.auth import get_user_model
from crewboardsdb.models import Event
from crewboardsdb.models import Request
from crewboardsdb.models import Event_Participant
from rest_framework import serializers


class UserSerializer(serializers.ModelSerializer):
    requests = serializers.StringRelatedField(many = True)
    event_admin = serializers.StringRelatedField(many = True)
    event_attendee= serializers.StringRelatedField(many = True)
    class Meta:
        model = get_user_model()
        fields = ('id','username','first_name','last_name','email','user_job_description','event_admin','requests', 'event_attendee',)

class EventSerializer(serializers.ModelSerializer):
    admin_user_id = serializers.StringRelatedField()
    class Meta:
        model = Event
        fields = ('id', 'event_name', 'admin_user_id', 'event_description', 'event_location',)
        lookup_field = 'admin_user_id'




class RequestSerializer(serializers.ModelSerializer):

    requester_user_id = serializers.StringRelatedField()
    class Meta:
        model = Request
        fields = ('id', 'request_desc', 'fulfilled_status','requester_user_id','fulfiller_user_id',)
        lookup_field = 'requester_user_id'




class EventParticipantSerializer(serializers.ModelSerializer):
    class Meta:
        model = Event_Participant
        fields = ('id', 'event_id', 'user_id')

Answer 1

希望这仍然是活跃的，刚刚遇到同样的问题并想出来。

在我的情况下，我也有完全相同的问题，外键关联的属性没有显示在可浏览的api中，所以我认为它必须是序列化器的东西。

原来这就是问题所在。如果您有ForeignKey约束，则根本不需要处理nestes序列化程序，只需将它们从序列化程序类中删除即可！

在你的情况下，它会是这样的：

(Event Model)
class Event(models.Model):
    def __str__(self):
         return self.event_name
    event_name = models.CharField(max_length = 100)
    event_location = models.CharField(max_length = 100)
    event_description = models.TextField(max_length = 300)
    admin_user_id = models.ForeignKey(User, related_name =    'event_admin')

此处admin_user_id可能是您的可浏览API中未显示的属性。

现在，这是该类的序列化程序必须如下所示：

class EventSerializer(serializers.ModelSerializer):
    class Meta:
        model = Event
        fields = ('id', 'event_name', 'admin_user_id', 'event_description', 'event_location',)
        lookup_field = 'admin_user_id'

请注意，只需删除行admin_user_id = serializers.StringRelatedField()即可完成作业，现在您的api应按预期显示该字段，并且您可以选择将该对象链接到的用户。

我在自己的项目中测试了你的问题，只需要你的模型和序列化器，按照这个简单的步骤完成工作！

希望这对您或将来的任何人都有帮助。欢呼声。

models.ForeignKey字段未显示在可浏览的API中

1 个答案: