使用引用外键的Django Rest API创建对象

时间:2018-12-14 20:54:34

标签: django django-models django-rest-framework django-serializer

很抱歉,如果有人问过这个问题,但是我已经仔细阅读了文档,甚至还有其他一些StackOverflow问题,似乎没有一个能解决我的问题。我对Django有点陌生,所以很抱歉,如果在其他地方回答了这个问题。

Django REST - Create object with foreign key using serializers) 仅按照此处建议的方式执行company_id无效。仍然没有到达那里。 还按照建议尝试了视图中的自定义创建功能,但也没有运气。

我有一个Company类,它带有2个值(id 1和2),还有一个Project类,其中包含一个返回到company_id的外键CompanyProject必须正好为1 Company

现在,我无法执行POST来创建Project。我尝试过专门引用company_id,甚至尝试引用序列化程序中的嵌套序列化程序。似乎没有任何作用。

我可能更希望在POST中发送company_id并在我GET时取回引用的对象。不过,在这一点上,我很高兴获得POST的支持。注意:默认的company_id值为1,因此我创建的第一个将实际起作用。只是所有后续的POST最终都会出现此错误: (1062, "Duplicate entry '1-RANDOM' for key 'project_project_company_id_key_007f87f8_uniq'")

公司

# Model
from django.db import models

class Company(models.Model):
    company = models.CharField(
        max_length=50,
        unique=True
    )


# Serializer
from rest_framework import serializers
from api.company.models import Company

class CompanySerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Company
        fields = ('url', 'company')


# View
from rest_framework import viewsets

from api.company.serializers import CompanySerializer
from api.company.models import Company


class CompanyViewSet(viewsets.ModelViewSet):
    queryset = Company.objects.all()
    serializer_class = CompanySerializer

项目

# Model
from django.db import models
from django.core.validators import RegexValidator

from api.company.models import Company


class Project(models.Model):
    DEFAULT_PK = 1

    class Meta:
        unique_together = (('company', 'key'),)

    company = models.ForeignKey(
        Company,
        on_delete=models.CASCADE,
        default=DEFAULT_PK,
        blank=False
    )
    key = models.CharField(
        max_length=8,
        blank=False,
        validators=[
            RegexValidator(
                regex='^[A-Z0-9\-]*$',
                message='Project key can only contain uppercase alphanumeric or a hythen (-)',
                code='invalid_key'
            ),
        ]
    )
    name = models.CharField(
        max_length=50,
        blank=False
    )
    description = models.CharField(
        max_length=500,
        blank=True
    )


# Serializer
from rest_framework import serializers
from api.project.models import Project

from api.company.serializers import CompanySerializer


class ProjectSerializer(serializers.HyperlinkedModelSerializer):
    #company = CompanySerializer(read_only=True) # Tried this to no avail.

    class Meta:
        model = Project
        fields = ('url', 'key', 'name', 'description', 'company_id') # 'company' here did not work

# View
from rest_framework import viewsets
from rest_framework.response import Response

from api.project.serializers import ProjectSerializer
from api.project.models import Project
from api.project.models import Company


class ProjectViewSet(viewsets.ModelViewSet):
    queryset = Project.objects.all()
    serializer_class = ProjectSerializer

# Tried playing around with this from suggestion I find in other post. No luck
"""
def create(self, validated_data):
    serializer = self.get_serializer(data=self.request.data)
    company_id_for_contact =  self.request.data.pop('company_id')
    company_instance = Company.objects.filter(id=company_id_for_contact).first()
    if not serializer.is_valid():
        print(serializer.errors)
    data = serializer.validated_data
    serializer.save(company=company_instance)
    headers = self.get_success_headers(serializer.data)
    return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)
"""

数据

# Note: the first one will work (default company_id is 1. Next one will not)
curl \
 -X POST \
 -H 'Content-Type: application/json' \
 -d '{"company_id":2,"key":"OTHER","name":"Other","description":"Other example."}' \
'http://0.0.0.0:8000/project/'

1 个答案:

答案 0 :(得分:0)

哇,我应该再等10分钟,我会弄清楚的。 curl POST需要company,而不是company_id。在CompanySerializer中不需要Project引用。

由于我使用的是url,因此我们只需要引用(http://0.0.0.0:8000/company/2/) HyperlinkedModelSerializer

希望有人在遇到类似问题时发现了这个问题:)