从 DELETE 请求中返回数据？

Question

我有一个简单的资源，我想执行 DELETE。成功后，我想获取已删除对象的 ID。根据文档，always_return_data - 指定所有 HTTP 方法（DELETE 除外）应返回数据的序列化形式。

http://django-tastypie.readthedocs.org/en/latest/resources.html#always-return-data

class SimpleResource(resources.MongoEngineResource):
    class Meta:
        queryset = Simple.objects.all()
        resource_name = 'simple'
        allowed_methods = ('get', 'put', 'post', 'delete', 'patch')
        always_return_data = True

问题： 无论如何要序列化数据以返回被删除的对象？

Answer 1

查看source 和documentation 的tastepie，看起来您需要覆盖ModelResource（MongoEngineResource inherits）的两个函数：

1. obj_delete 删除对象。

2. delete-detail 在 DELETE 请求上调用并调用 obj_delete 然后返回 204 No Content 或 404 Not Found

我没有使用过美味的派，所以这一切都是从查看文档开始的，但这至少是一个起点。你需要对你的班级做这样的事情：

class SimpleResource(resources.MongoEngineResource):
    class Meta:
        queryset = Simple.objects.all()
        resource_name = 'simple'
        allowed_methods = ('get', 'put', 'post', 'delete', 'patch')
        always_return_data = True


    def obj_delete(self, bundle, **kwargs):
        try:
            # get an instance of the bundle.obj that will be deleted
            deleted_obj = self.obj_get(bundle=bundle, **kwargs)
        except ObjectDoesNotExist:
            raise NotFound("A model instance matching the provided arguments could not be found.")
        # call the delete, deleting the obj from the database
        super(MongoEngineResource, self).obj_delete(bundle, **kwargs)
        return deleted_obj


    def delete_detail(self, request, **kwargs):
        bundle = Bundle(request=request)

        try:
            # call our obj_delete, storing the deleted_obj we returned
            deleted_obj = self.obj_delete(bundle=bundle, **self.remove_api_resource_names(kwargs))
            # build a new bundle with the deleted obj and return it in a response
            deleted_bundle = self.build_bundle(obj=deleted_obj, request=request)
            deleted_bundle = self.full_dehydrate(deleted_bundle)
            deleted_bundle = self.alter_detail_data_to_serialize(request, deleted_bundle)
            return self.create_response(request, deleted_bundle, response_class=http.HttpNoContent)
        except NotFound:
            return http.HttpNotFound()

Answer 2

您不需要返回已删除的对象。您可以只更新 obj_delete 中的 bundle.obj，然后将其返回到 delete_detail。 我正在使用自定义资源和中间件来运行 api，但如果你跳过元模型，它就很简单了。

def obj_delete(self,bundle, **kwargs):
    self.load_user_obj(bundle.request)
    l_instanceId = kwargs['pk']
    try:
        #load the instance
        self.m_objMetaModel.load(l_instanceId,True)

        #do the manipulation on it
        self.m_objMetaModel.REST_IMPL.delete()

        #get an instance back. In my case in the delete I
        #am creating a virtual instance- just an object that 
        #fits the other parts of the api
        bundle.obj = self.m_objMetaModel.instance

        #load the bundle manually
        self.m_objMetaModel.REST_IMPL.reload_data(bundle.obj,bundle.data)

        return bundle
    except Exception as e:
        print(e)

def delete_detail(self, request, **kwargs):
    bundle = Bundle(request=request)

    try:
        # perform the operation returning the recreated bundle
        deleted_bundle = self.obj_delete(bundle=bundle,
                                **self.remove_api_resource_names(kwargs))

        # keep the meta configuration, just to avoid surprises later
        if not self._meta.always_return_data:
            return http.HttpNoContent()
        else:
            #update the bundle, you can skip on the dehydrate if you 
            #are loading the bundle data manually
            deleted_bundle = self.full_dehydrate(deleted_bundle)
            deleted_bundle = self.alter_detail_data_to_serialize(request, 
                                                               deleted_bundle)
            return self.create_response(request, deleted_bundle)
    except NotFound:
            return http.HttpNotFound()