AttributeError while using Django Rest Framework with serializers

问题:

I am following a tutorial located here that uses Django Rest Framework, and I keep getting a weird error about a field.

I have the following model in my models.py

from django.db import models  class Task(models.Model):     completed = models.BooleanField(default=False)     title = models.CharField(max_length=100)     description = models.TextField() 

Then my serializer in serializers.py

from rest_framework import serializers  from task.models import Task  class TaskSerializer(serializers.ModelSerializer):      class Meta:         model = Task         fields = ('title', 'description', 'completed') 

and my views.py as follows:

from rest_framework import status from rest_framework.decorators import api_view from rest_framework.response import Response  from task.models import Task from api.serializers import TaskSerializer       @api_view(['GET', 'POST'])     def task_list(request):         """         List all tasks, or create a new task         """         if request.method == 'GET':             tasks = Task.objects.all()             serializer = TaskSerializer(tasks)             return Response(serializer.data)          elif request.method == 'POST':             serializer = TaskSerializer(data=request.DATA)             if serializer.is_valid():                 serializer.save()                 return Response(serializer.data, status=status.HTTP_201_CREATED)             else:                 return Response(                     serializer.errors, status=status.HTTP_400_BAD_REQUEST                 ) 

and my urls.py has this line:

url(r'^tasks/$', 'task_list', name='task_list'), 

When I try accessing curl http://localhost:9000/api/tasks/, I keep getting the following error and I'm not sure what to make of it:

AttributeError at /api/tasks/ Got AttributeError when attempting to get a value for field `title` on serializer `TaskSerializer`. The serializer field might be named incorrectly and not match any attribute or key on the `QuerySet` instance. Original exception text was: 'QuerySet' object has no attribute 'title'. 

What I'm I missing?

回答1:

Simple specify many=True when creating a serializer from queryset, TaskSerializer(tasks) will work only with one instance of Task:

tasks = Task.objects.all() serializer = TaskSerializer(tasks, many=True) 

回答2:

The problem here is that you are trying to convert a Queryset(list) of entries into a single entry. The solution is something along these lines.

from rest_framework import serializers  class TaskListSerializer(serializers.ListSerializer):     child = TaskSerializer()     allow_null = True     many = True 

Then

if request.method == 'GET':         tasks = Task.objects.all()         serializer = TaskListSerializer(tasks)         return Response(serializer.data) 

文章来源: AttributeError while using Django Rest Framework with serializers