serializers.py

from rest_framework import serializers

from taggit.managers import TaggableManager
from rp.models import Article

class TagListSerializer(serializers.Field):
    class Meta:
        model = TaggableManager(blank=True)

    def to_representation(self, obj):
        if type(obj) is not list:
            return [tag.name for tag in obj.all()]
        return obj

class ArticleSerializer(serializers.ModelSerializer):
    tags = TagListSerializer()

    class Meta:
        model = Article
        fields = ('id', 'url', 'title', 'tags', 'extracts', 'und_score_up', 'und_score_down')