Django 序列化程序无法将查询集序列化为 JSON

尝试简单的 Django 序列化器。我使用具有特定值的 queryset 然后我将 queryset 或 queryset.values() 传递给序列化器。为什么会出现500错误？

@csrf_protect
def geoLookup(request, **kwargs):
country = kwargs.get('Country')
city = kwargs.get('Place')
queryset = GeoNames_location.objects.filter(geoCountry_code=country, feature_class='P',     geoAsciiName__istartswith=city).values_list("geoAsciiName",  "geoLongitude", "geoLatitude",  "geo_timezone", "geo_population", "geoCountry_code").order_by('-geo_population')[:5]
data = serializers.serialize("json", queryset.values()) # tried queryset and     queryset.values()
parsed_data = json.loads(data)
pretty_json = json.dumps(parsed_data, indent=4)
return JsonResponse(json.loads(pretty_json), safe=False)


[24/Jul/2024 06:07:52] "GET /edit_chart_form HTTP/1.1" 200 18929
Internal Server Error: /geolookup/US/p
Traceback (most recent call last):
File "C:\Users\user\AppData\Local\Programs\Python\Python311\Lib\site-packages\django\core\handlers\exception.py", line 55, in inner
response = get_response(request)
           ^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\user\AppData\Local\Programs\Python\Python311\Lib\site-packages\django\core\handlers\base.py", line 197, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\user\AppData\Local\Programs\Python\Python311\Lib\site-packages\django\utils\decorators.py", line 188, in _view_wrapper
result = _process_exception(request, e)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\user\AppData\Local\Programs\Python\Python311\Lib\site-packages\django\utils\decorators.py", line 186, in _view_wrapper
response = view_func(request, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "G:\My Drive\myProgram\runtime\devui\ui\views.py", line 81, in geoLookup
data = serializers.serialize("json", queryset.values())
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\user\AppData\Local\Programs\Python\Python311\Lib\site-packages\django\core\serializers\__init__.py", line 134, in serialize
s.serialize(queryset, **options)
File "C:\Users\user\AppData\Local\Programs\Python\Python311\Lib\site-packages\django\core\serializers\base.py", line 113, in serialize
concrete_model = obj._meta.concrete_model
                 ^^^^^^^^^
AttributeError: 'dict' object has no attribute '_meta'
[24/Jul/2024 06:07:55] "GET /geolookup/US/p HTTP/1.1" 500 105779

出现的错误是因为你尝试将 Django 序列化器用于列表字典，而 Django 序列化器是为 Django 模型实例设计的。 queryset.values() 返回一个列表字典，而不是 Django 模型实例的查询集。

以下是如何解决此问题的几种方法：

1. 使用 values 方法返回数据：

你不需要使用 serializers.serialize 。 values 方法已经为你提供了一个字典列表，你可以直接将其传递给 JsonResponse ：

```python from django.http import JsonResponse

@csrf_protect def geoLookup(request, **kwargs): country = kwargs.get('Country') city = kwargs.get('Place') queryset = GeoNames_location.objects.filter( geoCountry_code=country, feature_class='P', geoAsciiName__istartswith=city ).values( "geoAsciiName", "geoLongitude", "geoLatitude", "geo_timezone", "geo_population", "geoCountry_code" ).order_by('-geo_population')[:5] return JsonResponse(list(queryset), safe=False) ```

2. 使用 Django REST framework：

如果你需要对序列化数据进行更多控制，或者计划构建 API，Django REST framework 是一个很好的选择。它提供了序列化器，可以轻松地将 Django 模型转换为 JSON。

```python from rest_framework import serializers from rest_framework.decorators import api_view from rest_framework.response import Response

from myapp.models import GeoNames_location

class GeoLocationSerializer(serializers.ModelSerializer): class Meta: model = GeoNames_location fields = ["geoAsciiName", "geoLongitude", "geoLatitude", "geo_timezone", "geo_population", "geoCountry_code"]

@api_view(['GET']) def geoLookup(request, **kwargs): country = kwargs.get('Country') city = kwargs.get('Place') queryset = GeoNames_location.objects.filter( geoCountry_code=country, feature_class='P', geoAsciiName__istartswith=city ).order_by('-geo_population')[:5] serializer = GeoLocationSerializer(queryset, many=True) return Response(serializer.data) ```

请注意，使用 Django REST framework 需要安装它 ( pip install djangorestframework ) 并将其添加到你的 INSTALLED_APPS 设置中。

这些方法都将返回你想要的 JSON 数据。选择最适合你需求和项目结构的方法。