摆脱 django rest 框架序列化 SearchQuerySet 中的“对象”包装器

Question

我用 DRF 序列化 Django Haystack 的 SearchQueryStack，如下所示，在生成的 JSON 响应中，我想摆脱围绕我的 Post 模型的对象包装器：

{
"count": 6, 
"next": null, 
"previous": null, 
"start_index": 1, 
"end_index": 6, 
"num_pages": 1, 
"results": [
    {
        "postWrapper": {
            "hitcount": {
                "counter": 9, 
                "id": 251
            }, 
            "id": 277, 
            "content": "test", 
            "owner": {...

这是我想要的 JSON（没有 postWrapper）：

    {
"count": 6, 
"next": null, 
"previous": null, 
"start_index": 1, 
"end_index": 6, 
"num_pages": 1, 
"results": [
    {
            "hitcount": {
                "counter": 9, 
                "id": 251
            }, 
            "id": 277, 
            "content": "test", 
            "owner": {...

这是视图：

class PostSearch(generics.ListAPIView):
model = Post

def get(self, request, *args, **kwargs):
    # simplified filtering of an SQS
    q = request.GET.get('q')
    sqs = SearchQuerySet().filter(content=q)
    paginator = Paginator(sqs, 10)
    page = request.GET.get('page')
    try:
        posts = paginator.page(page)
    except PageNotAnInteger:
        # If page is not an integer, deliver first page
        posts = paginator.page(1)
    except EmptyPage:
        # If page is out of range (e.g. 9999), deliver last page of results.
        posts = paginator.page(paginator.num_pages)

    serializer_context = {'request': request}
    serializer = PaginatedPostSerializer(posts, context=serializer_context)
    ret = serializer.data

    return response.Response(ret)

class SearchSerializer(serializers.Serializer):
object = PostSerializer()

def to_representation(self, obj):
    """
    Object instance -> Dict of primitive datatypes.
    """
    ret = OrderedDict()
    fields = [field for field in self.fields.values() if not field.write_only]

    for field in fields:
        try:
            attribute = field.get_attribute(obj)
            if field.field_name == 'object':
                field.field_name = 'postWrapper'
        except SkipField:
            continue

        if attribute is not None:
            ret[field.field_name] = field.to_representation(attribute)

    return ret

这里是序列化器：

class SearchSerializer(serializers.Serializer):
    object = PostSerializer()

    def to_representation(self, obj):
        """
        Object instance -> Dict of primitive datatypes.
        """
        ret = OrderedDict()
        fields = [field for field in self.fields.values() if not field.write_only]

        for field in fields:
            try:
                attribute = field.get_attribute(obj)
                if field.field_name == 'object':
                    field.field_name = 'postWrapper'
            except SkipField:
                continue

            if attribute is not None:
                ret[field.field_name] = field.to_representation(attribute)

        return ret


class PaginatedPostSerializer(pagination.PaginationSerializer):

    start_index = serializers.SerializerMethodField()
    end_index = serializers.SerializerMethodField()
    num_pages = serializers.ReadOnlyField(source='paginator.num_pages')

    class Meta:
        object_serializer_class = SearchSerializer

    def get_start_index(self, page):
        return page.start_index()

    def get_end_index(self, page):
        return page.end_index()

    def get_curr_page(self, page):
        return page.number

这里是 PostSerializer：

class PostSerializer(serializers.ModelSerializer):
    owner = UserSerializer(required=False, read_only=True)
    category_edit = serializers.PrimaryKeyRelatedField(queryset=Category.objects.all(), write_only=True)
    category = CategorySerializer(read_only=True)
    price = serializers.CharField()
    price_currency = serializers.CharField()
    hitcount = serializers.SerializerMethodField()
    images = ImageSerializer(many=True, read_only=True)

    def get_hitcount(self, context):
        # Content_type for Post is 20
        c_type = ContentType.objects.get_for_model(context)
        obj, created = HitCount.objects.get_or_create(content_type=c_type, object_pk=context.id)
        data = {}
        data["id"] = obj.pk
        data["counter"] = obj.hits
        return data

    class Meta:
        model = Post
        fields = ('hitcount', 'id', 'content', 'owner', 'category', 'category_edit', 'images', 'price', 'price_currency')

如您所见，我能得到的最接近的是将“object”包装器重命名为“postWrapper”。我想将其作为包装器完全删除，因此“结果”内只有 Post 模型列表，其中包含“hitcount”、“id”、“内容”、“所有者”等...

非常感谢任何帮助。提前致谢。

Answer 1

我认为在你的PaginatedPostSerializer 中使用PostSerializer 作为你的object_serializer_class 就是你想要的。

class PaginatedPostSerializer(pagination.PaginationSerializer):
      class Meta:
            object_serializer_class = PostSerializer

如果您想覆盖to_representation，您可以扩展 PostSerializers，而不是将其作为新字段添加到新序列化程序中。

p.s.：如果您想将结果项包装在 postWrapper 中，则无需覆盖 to_representation 函数，只需在 SearchSerializer 中重命名即可：

class SearchSerializer(serializers.Serializer):
    # object = PostSerializer()
    # rename the object to what you want
    postWrapper = PostSerializer() 

我想我误解了你的查询集的样子，所以请在上面回答。

class SearchSerializer(serializers.Serializer):
    object = PostSerializer()

    def to_representation(self, instance):
        res = super(SearchSerializer, self).to_representation(instance)
        # pop of the object field, and push the fields inside the object to parent level
        objectfield = res.pop('object', None)
        if objectfield:
            for field, value in objectfield.iteritems():
                res[field] = value
        return res

恕我直言，将您的查询集更改为Post 模型查询集，并将分页序列化器的object_serializer_class 设置为PostSerializer 更有意义。

Answer 2

所以我将它添加到我的 PostSearch 视图中，它解决了我的问题：

    ret = serializer.data
    new_result_list = []
    results = ret.get('results')
    for orderedDict in results:
        post = orderedDict.get('object')
        new_result_list.append(post)

    ret['results'] = new_result_list

基本上，我创建了一个没有“对象”包装器的新列表并将其放回返回值。