python - 如何序列化类对象特定字段的数组(getStream)

Question

我正在尝试将 EnrichedActivity 数据推送到 FeedSerializer。我正在使用 getStream

获取 Feed 数据

class FeedAPIView(APIView):
    def get(self, request, format=None):
        feeds = feed_manager.get_news_feeds(request.user.id)
        # get the newsfeed for user.
        activities = feeds.get('timeline').get()['results']
        activities = enricher.enrich_activities(activities)
        # I want to serialize only Outfit instances(object) from the activities.
        filtered_set = FeedSerializer(activities.getObject.convertToQueryset)
        json_output = { "feed" : filtered_list }
        return Response(json_output, status=status.HTTP_200_OK)

这是来自事件的数组数据

[
    EnrichedActivity(
        activity_data={
            'target': None, 'verb': 'outfit', 'actor': <User: georgiamason522>, 
            'to': [], 'foreign_id': 'outfit.Outfit:23',
            'id': 'x7x7bxxxxxxxxxxx3xbxx', 
            'object': <Outfit: georgiamason522 23>, // Data
            'time': datetime.datetime(2017, 12, 14, 1, 36, 6, 833617), 'origin': 'user:17'}, 
            not_enriched_data={}), 
    EnrichedActivity(..., 'object': <Outfit: georgiamason522 22>,
]

我想从上面的数组中获取这个查询集，

filtered_set = ???
print(filtered_set)
<QuerySet [<Outfit: georgiamason522 23>, <Outfit: georgiamason522 22>]>

将查询集放入 FeedSerializer。

FeedSerializer(filtered_set, many=True, context={'request': self.context['request']}).data

我的问题是...

1. EnrichedActivity 数据看起来像类对象。我们如何仅提取 activity_data > object。

2. 将提取的对象数据转换为查询集

这是伪代码，可能是正确的。

# This is Pseudo Code in my mind! This is not correct or can be not even close
filtered_set = [activity.activity_data.object].getQueryset for activity in activities

如果有任何不清楚或需要更多信息，请在下面发表评论。

更新

class FeedSerializer(serializers.ModelSerializer):
    comments = serializers.SerializerMethodField()
    ...
    is_owner = serializers.SerializerMethodField()

    class Meta:
        model = Outfit # I want to serialize Outfit Model instance 
                       # from feed in enriched list

    ...

服装模型//你可以把它想象成普通的帖子

class Outfit(models.Model, Activity):
    user = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, blank=True)
    ...

    @property
    def get_content_type(self):
        instance = self
        content_type = ContentType.objects.get_for_model(instance.__class__)
        return content_type

    @property
    def activity_object_attr(self):
        return self

    @property
    def activity_notify(self):
        targets = [feed_manager.get_news_feeds(self.user.id)['timeline']]

Answer 1

这是我的解决方案。感谢...@DwightGunning

    feed = []
    for activity in activities:
        outfit_instance = activity.__dict__.get('activity_data').get('object')
        data = FeedSerializer(
            outfit_instance,
            context={'request': request}).data
        feed.append(data)

    json_output = { "feed" : feed }