【发布时间】：2015-11-14 09:14:23
【问题描述】：
考虑一个具有关联类别的列表模型。我想通过对数据进行 POST 来为现有类别创建一个新列表：
{"title": "myapp", "category": {"name": "Business"}}，其中title 是应创建的列表的标题，Business 是用于此新列表的现有类别的名称。
当我尝试发出这样的请求并为此实例化 ListingSerializer 时，我收到一个错误，指出类别名称必须是唯一的 - 我不想创建新类别，而是使用现有类别.我尝试将类别字段上的验证器设置为 []，但这并没有改变行为。
我可以使用SlugRelatedField，但这会迫使我的请求数据看起来更像{"title": "myapp", "category": "Business"}，这不是我想要的。我尝试使用SlugRelatedField 的source 参数来指定嵌套关系，但这也不起作用：
category = serializers.SlugRelatedField(
slug_field='category.name',
queryset=models.Category.objects.all()
)
产量：
"category": [
"Object with name={'name': 'Business'} does not exist."
]
models.py：
import django.contrib.auth
from django.db import models
from django.conf import settings
class Profile(models.Model):
display_name = models.CharField(max_length=255)
user = models.OneToOneField(settings.AUTH_USER_MODEL)
class Category(models.Model):
name = models.CharField(max_length=50, unique=True)
description = models.CharField(max_length=200)
class Listing(models.Model):
title = models.CharField(max_length=50, unique=True)
category = models.ForeignKey(Category, related_name='listings', null=True)
owners = models.ManyToManyField(
Profile,
related_name='owned_listings',
db_table='profile_listing',
blank=True
)
serializers.py:
import logging
import django.contrib.auth
from rest_framework import serializers
import myapp.models as models
logger = logging.getLogger('mylogger')
class ShortUserSerializer(serializers.ModelSerializer):
class Meta:
model = django.contrib.auth.models.User
fields = ('username', 'email')
class ProfileSerializer(serializers.ModelSerializer):
user = ShortUserSerializer()
class Meta:
model = models.Profile
fields = ('user', 'display_name')
read_only = ('display_name',)
class CategorySerializer(serializers.ModelSerializer):
class Meta:
model = models.Category
fields = ('name', 'description')
read_only = ('description',)
class ListingSerializer(serializers.ModelSerializer):
owners = ProfileSerializer(required=False, many=True)
# TODO: how to indicate that this should look for an existing category?
category = CategorySerializer(required=False, validators=[])
class Meta:
model = models.Listing
depth = 2
def validate(self, data):
logger.info('inside ListingSerializer validate')
return data
def create(self, validated_data):
logger.info('inside ListingSerializer.create')
# not even getting this far...
views.py：
import logging
from django.http import HttpResponse
from django.shortcuts import get_object_or_404
import django.contrib.auth
from rest_framework import viewsets
from rest_framework.response import Response
import myapp.serializers as serializers
import myapp.models as models
# Get an instance of a logger
logger = logging.getLogger('mylogger')
class CategoryViewSet(viewsets.ModelViewSet):
queryset = models.Category.objects.all()
serializer_class = serializers.CategorySerializer
class UserViewSet(viewsets.ModelViewSet):
queryset = django.contrib.auth.models.User.objects.all()
serializer_class = serializers.ShortUserSerializer
class ProfileViewSet(viewsets.ModelViewSet):
queryset = models.Profile.objects.all()
serializer_class = serializers.ProfileSerializer
class ListingViewSet(viewsets.ModelViewSet):
logger.info('inside ListingSerializerViewSet')
queryset = models.Listing.objects.all()
serializer_class = serializers.ListingSerializer
【问题讨论】：
-
非常彻底。我很惊讶这没有尽快得到答复。
标签： django django-rest-framework