django rest框架中的IntegrityError

Question

我正在玩DRF並做了一個簡單的博客，匿名人員可以在博客文章中發表評論。我現在只是使用可瀏覽的API，並且在我嘗試發表評論之前，似乎一切正常。 DELETE，GET和PUT都按預期工作，只有POST。

我得到的錯誤是IntegrityError at /api/posts/i-had-a-blog-his-name-was-bingo/comments/: blog_comment.blogpost_id may not be NULL

我已經徹底搜查了一個答案，爲什麼這可能發生，但沒有什麼幫助。這裏是我的代碼...

models.py

class BlogPost(models.Model): 
    created = models.DateTimeField(auto_now_add=True) 
    owner = models.ForeignKey('auth.User', related_name='posts') 
    title = models.CharField(max_length=100, unique=True) 
    content = models.TextField() 
    slug = models.SlugField(max_length=100, unique=True, editable=False) 
    def save(self, *args, **kwargs): 
     self.slug = slugify(self.title) 
     super(BlogPost, self).save(*args, **kwargs) 
    @permalink 
    def get_absolute_url(self): 
     return ('post-detail', { 'slug': self.slug }) 
    class Meta: 
     ordering = ('created',) 

class Comment(models.Model): 
    created = models.DateTimeField(auto_now_add=True) 
    blogpost = models.ForeignKey(BlogPost, related_name='comments') 
    author = models.CharField(max_length=100, blank=False) 
    content = models.TextField() 
    class Meta: 
     ordering = ('created', 'author', 'content') 

serializers.py

class CommentSerializer(serializers.HyperlinkedModelSerializer): 
    post = serializers.Field(source='blogpost.title') 

    class Meta: 
     model = Comment 
     fields = ('id', 'author', 'content', 'post')  


class BlogPostSerializer(serializers.HyperlinkedModelSerializer): 
    owner = serializers.Field(source='owner.username') 
    url = serializers.HyperlinkedIdentityField(view_name='post-detail') 
    comments = serializers.HyperlinkedIdentityField(view_name='comment-list') 

    class Meta: 
     model = BlogPost 
     fields = ('url', 'id', 'title', 'content', 'owner', 'comments') 

views.py

class CommentList(generics.ListCreateAPIView): 
    serializer_class = CommentSerializer 

    def get_queryset(self): 
     slug = self.kwargs['slug'] 
     return Comment.objects.filter(blogpost__slug=slug) 


class CommentDetail(generics.RetrieveUpdateDestroyAPIView): 
    serializer_class = CommentSerializer 
    permission_classes = (IsAdminOrNoEdit,) 

    def get_queryset(self): 
     slug = self.kwargs['slug'] 
     return Comment.objects.filter(blogpost__slug=slug) 

urls.py

commentpatterns = patterns('', 
    url(r'^$', views.CommentList.as_view(), name='comment-list'), 
    url(r'^(?P<pk>[0-9]+)/$', views.CommentDetail.as_view(), name='comment-detail'), 
) 


urlpatterns = patterns('blog.views', 
    url(r'^$', 'api_root'), 
    url(r'^posts/$', views.PostList.as_view(), name='post-list'), 
    url(r'^posts/(?P<slug>[-\w]+)/$', views.PostDetail.as_view(), name='post-detail'), 
    url(r'^posts/(?P<slug>[-\w]+)/comments/', include(commentpatterns)), 
    url(r'^users/$', views.UserList.as_view(), name='user-list'), 
    url(r'^users/(?P<pk>[0-9]+)/$', views.UserDetail.as_view(), name='user-detail'), 
) 

任何幫助將不勝感激，這是推動我瘋了。

Answer 1

你Comment模型定義了ForeignKey，這是不允許的是null：

class Comment(models.Model): 
    ... 
    blogpost = models.ForeignKey(BlogPost, related_name='comments') 
    ... 

這是確定的，但你的串行不包括blogpost ID，所以即使你的請求包括，它會被忽略。糾正你的序列化包括blogpost場：現在

class CommentSerializer(serializers.HyperlinkedModelSerializer): 
    post = serializers.Field(source='blogpost.title') 
    blogpost = serializers.PrimaryKeyRelatedField() 

    class Meta: 
     model = Comment 
     fields = ('id', 'author', 'content', 'post', 'blogpost') 

當你創建一個POST請求，該blogpost字段應包含博客文章的id到你安裝此評論。