'dict' object has no attribute 'pk' Django Rest API Framework

Question

Im using Django Rest API Framework, I want to upload multiple images for a single project using Angular js.

Here's my model:

class Project(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)
    owner = models.ForeignKey(User)
    number_of_photos = models.IntegerField()

class Photo(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)
    images = models.ImageField(upload_to='photos/', max_length=254)
    project = models.ForeignKey(Project)

I have this serializers:

class ProjectSerializer(serializers.ModelSerializer):
    class Meta:
        model = Project
        fields = ('id', 'created', 'number_of_photos', 'owner')

    def create(self, validated_data):
        project = Project.objects.create(**validated_data)
        return project

class UploadSerializer(serializers.ModelSerializer):
    project = ProjectSerializer(many=True, read_only=True)

    class Meta:
        model = Photo
        fields = ('url', 'created', 'images', 'project')

In my view I got this inside my viewsets.ModelViewSet

serializer = UploadSerializer(data=photo_array, many=True, context={'request': request})

if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)

The variable photo_array contains:

[{'project': u'1', 'images': {u'name': u'test-image.png', u'lastModifiedDate': u'2015-04-22T08:51:11.000Z', u'webkitRelativePath': u'', u'lastModified': 1429692671000, u'type': u'image/png', u'size': 43152}}, {'project': u'1', 'images': {u'name': u'test.png', u'lastModifiedDate': u'2015-04-08T08:35:17.000Z', u'webkitRelativePath': u'', u'lastModified': 1428482117000, u'type': u'image/png', u'size': 127433}}]

But it gives me an error 'dict' object has no attribute 'pk'

Did my photo_array variable cause this problem?.

Answer 1

Without a traceback, I can only take an educated guess as to what the issue actually is.

You are using a standard ModelSerializer and you are allowing Django REST framework to generate your fields for you. You can introspect the generated fields by printing the output of repr(UploadSerializer()) , but they should look something like this:

class UploadSerializer(ModelSerializer):
    url = HyperlinkedIdentityField()
    created = DateTimeField()
    images = ImageField()
    project = ProjectSerializer(many=True, read_only=True)

    class Meta:
        model = Photo
        fields = ('url', 'created', 'images', 'project')

With those fields, a typical dictionary that would be passed back from the serializer should look something like

{
    "id": 1,
    "url": "http://localhost:8000/api/photos/1/",
    "created": "2015-04-22T08:51:11.000Z",
    "images": "http://localhost:8000/media/test-image.png",
    "project": {
        "id": 1,
        "created": "2015-04-22T08:51:11.000Z",
        "number_of_photos": 1,
        "owner": 1
    }
}

You'll notice that this is completely different from what you are passing in. You are passing in the data that would match a serializer that looks like

class UploadSerializer(ModelSerializer):
    url = HyperlinkedIdentityField()
    created = DateTimeField()
    images = SomeCustomImageField()
    project = PrimaryKeyRelatedField()

    class Meta:
        model = Photo
        fields = ('url', 'created', 'images', 'project')

So that does answer your secondary question

Did my photo_array variable cause this problem?

Most likely. Now, I don't actually know what your issue is. It sounds like you are passing a dictionary into a PrimaryKeyRelatedField , but your serializers don't actually match up.

Answer 2

我认为您应该使用id字段更新UploadSerializer