我想按字段名称过滤并取回一个子集,而不是取回我所有的字段名称。例如这里我按 id 和 name 过滤。它应该只以 json 格式返回这两个维度。我在网站上找到了许多解决方案,并且我按照建议做了完全一样的事情,但我没有得到预期的结果。请你帮助我好吗 ?
我的 urls.py:
router = routers.DefaultRouter()
urlpatterns = [
path('', include(router.urls)),
path('edges/', edge_list),
path('edges/<int:pk>/', edge_detail),
path('network/<int:pk>/edges/', edges_of_a_network),
]
我的观点
@api_view(['GET', 'POST'])
def edge_list(request):
"""
List all edges of all networks, or create a new edge.
"""
if request.method == 'GET':
edges = Edge.objects.all()
serializer = EdgeSerializer(edges, many=True)
return Response(serializer.data)
elif request.method == 'POST':
serializer = EdgeSerializer(data=request.data)
if serializer.is_valid():
serializer.save()
return Response(serializer.data, status=status.HTTP_201_CREATED)
return Response(serializer.error, status=status.HTTP_400_BAD_REQUEST)
这是来自https://www.django-rest-framework.org/api-guide/serializers/#example的复制过去示例
class DynamicFieldsModelSerializer(serializers.ModelSerializer):
"""
A ModelSerializer that takes an additional `fields` argument that
controls which fields should be displayed.
"""
def __init__(self, *args, **kwargs):
# Don't pass the 'fields' arg up to the superclass
fields = kwargs.pop('fields', None)
# Instantiate the superclass normally
super(DynamicFieldsModelSerializer, self).__init__(*args, **kwargs)
if fields is not None:
# Drop any fields that are not specified in the `fields` argument.
allowed = set(fields)
existing = set(self.fields)
for field_name in existing - allowed:
self.fields.pop(field_name)
我想过滤字段的序列化程序类。
class EdgeSerializer(DynamicFieldsModelSerializer, serializers.ModelSerializer):
source = serializers.SerializerMethodField(method_name='get_node_source')
target = serializers.SerializerMethodField(method_name='get_node_target')
road_type = serializers.SerializerMethodField(
method_name='get_road_type_id')
class Meta:
model = Edge
fields = (
'id', 'edge_id', 'name', 'length', 'speed',
'lanes', 'param1', 'param2', 'param3', 'network',
'road_type', 'source', 'target'
)
def get_road_type_id(self, instance):
return {"id": instance.road_type.road_type_id,
"name": instance.road_type.name}
def get_node_source(self, instance):
return {"node_id":instance.source.node_id, "node_name": instance.source.name}
def get_node_target(self, instance):
return {"node_id":instance.target.node_id, "node_name": instance.target.name}