使用Django REST框架序列化程序将JSON请求保存到数据库

Question

我对Django完全陌生，出于某种原因，我不得不直接跳转到Django REST框架。我想在数据库中保存作为POST请求发送的JSON对象。JSON对象如下所示：

[{
    "title": "Bitcoin Price Likely to Reach $50K Soon According to This Indicator",
    "description": "",
    "date": "2021-02-09T09:08:58Z",
    "link": "https://cryptopotato.com/bitcoin-price-likely-to-reach-50k-soon-according-to-this-indicator/",
    "keywords": [{
        "name": "bitcoin"
    }],
    "source": "https://cryptocompare.com"
},
{
    "title": "Post-Tesla News FOMO Helps Bitcoin Price to Surge Above $48,000",
    "description": "",
    "date": "2021-02-09T09:08:58Z",
    "link": "https://www.cryptoglobe.com/latest/2021/02/post-tesla-news-fomo-helps-bitcoin-price-to-surge-above-48000/",
    "keywords": [{
        "name": "bitcoin"
    }],
    "source": "https://cryptocompare.com"
}]

我创建了这样的模型：

class Keywords(models.Model):
    name = models.CharField(max_length=20)

    def __str__(self):
        return self.name


class News(models.Model):
    title = models.CharField(max_length=100)
    description = models.TextField()
    date = models.DateTimeField()
    link = models.URLField()
    keywords = models.ManyToManyField(Keywords)
    source = models.CharField(max_length=30)

    class Meta:
        db_table = "News"
        # ordering = "-date"

    def __str__(self):
        return self.title

序列化程序：

class KeywordSerializer(serializers.ModelSerializer):
    class Meta:
        model = Keywords
        fields = ["name"]


class NewsSerializer(serializers.ModelSerializer):
    keywords = KeywordSerializer(read_only=True, many=True)

    class Meta:
        model = News
        fields = ["title", "description", "date", "link", "keywords", "source"]

最后是我的观点：

class NewsView(APIView):
    def post(self, request):    
        news_serializer = NewsSerializer(data=request.data, many=True)

        try:
            if news_serializer.is_valid():
                news_serializer.save()
                return Response("Created successfully", status=status.HTTP_201_CREATED)

        except Exception as e:
            print(e)

        return Response("Error, Don't know what", status=status.HTTP_400_BAD_REQUEST)

通常情况下，我尽量不发布模糊和一般性的问题，但在这篇文章中，我完全不知道如何在这里调试和发现问题。我从终点站得到的唯一东西是

Bad Request: /news/

你能指出问题所在，并给出解决方法吗？

Answer 1

好的，可能存在验证错误。

模型中需要描述，您传递的是空的。

      try:
            if news_serializer.is_valid():
                news_serializer.save()
                return Response("Created successfully", status=status.HTTP_201_CREATED)
           else: 
              print(news_serializer.errors)
              return Response('Invalid data') # whatever you want

阅读https://www.django-rest-framework.org/api-guide/validators/#validation-in-rest-framework

Answer 2

让我来帮你解决这个问题。

在当前状态下，解决方案是重写NewsSerializer的create方法来创建新闻和关键字实例。

class NewsSerializer(serializers.ModelSerializer):

  ...
  def create(self, validated_data):
    keywords = validated_data.pop("keywords", None)

    news, _ = News.objects.get_or_create(**validated_data)
   
    if news:
       for keyword in keywords:
           keyword, _ = Keywords.objects.get_or_create(**keyword)
           news.keywords.add(key)
    return news

此外，我将更新视图的post方法，如下所示：

...
def post(self, request):
   for news in request.data:
       serializer = NewsSerializer(news)
       serializer.save(raise_exception=True)
return Response("Created successfully", status=status.HTTP_201_CREATED)
...