Django Rest 序列化器返回空

Question

我正在学习本教程 (Django Rest Framework)，但在尝试使用序列化程序时遇到了问题。它返回一个空结果，而不是它应该返回的 49086 条记录。我的查询没问题，因为当我尝试在没有序列化程序的情况下显示数据时，它会显示这些数据。请问，我做错了什么？

models.py

# coding=utf-8

from __future__ import unicode_literals
from django.db import models


class Workers(models.Model):
    chapa = models.IntegerField(primary_key=True)
    emp_cod = models.IntegerField(primary_key=False)
    class Meta:
        managed = False
        db_table = 'WORKERS'

serializers.py

from rest_framework import serializers
from .models import Workers


class WorkersSerializer(serializers.ModelSerializer):
    class Meta:
        model = Workers
        fields = '__all__'

views.py

...
@api_view(['GET'])
@permission_classes((permissions.AllowAny,))
def get_all_workers(request):
    data = Workers.objects.using('rh').all().order_by('emp_cod')
    print(data.count()) # Returns 49086
    serializer = WorkersSerializer(data)
    print(serializer.data) # Returns {}
    json = JSONRenderer().render(serializer.data)
    return Response(json) # Returns Django Rest standard page with "{}" data

Answer 1

您应该使用many=True 序列化程序的参数来序列化多个对象。您也可以将serializer.data 直接作为Response 参数传递：

@api_view(['GET'])
@permission_classes((permissions.AllowAny,))
def get_all_workers(request):
    data = Workers.objects.using('rh').all().order_by('emp_cod')
    serializer = WorkersSerializer(data, many=True)
    return Response(serializer.data)

由于您的视图一次返回这么多对象，建议您添加pagination：

from rest_framework.pagination import PageNumberPagination

@api_view(['GET'])
@permission_classes((permissions.AllowAny,))
def get_all_workers(request):
    data = Workers.objects.using('rh').all().order_by('emp_cod')
    paginator = PageNumberPagination()
    paginator.page_size = 10
    result_page = paginator.paginate_queryset(data, request)
    serializer = WorkersSerializer(result_page, many=True)
    return Response(serializer.data)