Question

Why doesn’t my resource with a ManyToManyField update with this PUT request?

curl --dump-header - -H "Content-Type: application/json" -X PUT --data '{"uuid":"blah","pass_token":"blah","favorites": ["/api/v1/organizations/1/"]}' http://localhost:8000/api/v1/devices/2/

I get this response:

HTTP/1.0 400 BAD REQUEST
Date: Wed, 11 Jul 2012 22:21:15 GMT
Server: WSGIServer/0.1 Python/2.7.2
Content-Type: application/json; charset=utf-8

{"favorites": ["\"/api/v1/organizations/1/\" is not a valid value for a primary key."]}

Here are my resources:

class OrganizationResource(ModelResource):
    parent_org = fields.ForeignKey('self','parent_org',null=True, full=True,blank=True)

    class Meta:
        allowed_methods = ['get',]
        authentication = APIAuthentication()
        fields = ['name','org_type','parent_org']
        filtering = {
            'name': ALL,
            'org_type': ALL,
            'parent_org': ALL_WITH_RELATIONS,
        }
        ordering = ['name',]
        queryset = Organization.objects.all()
        resource_name = 'organizations'

class DeviceResource(ModelResource):
    favorites = fields.ManyToManyField(OrganizationResource,'favorites',null=True,full=True)

    class Meta:
        allowed_methods = ['get','patch','post','put',]
        authentication = APIAuthentication()
        authorization = APIAuthorization()
        fields = ['uuid',]
        filtering = {
            'uuid': ALL,
        }
        queryset = Device.objects.all()
        resource_name = 'devices'
        validation = FormValidation(form_class=DeviceRegistrationForm)

A get on the OrganizationResource gives this exchange:

curl --dump-header - -H "Content-Type: application/json" -X GET http://localhost:8000/api/v1/organizations/1/

HTTP/1.0 200 OK
Date: Wed, 11 Jul 2012 22:38:30 GMT
Server: WSGIServer/0.1 Python/2.7.2
Content-Type: application/json; charset=utf-8

{"name": "name", "org_type": "org_type", "parent_org": null, "resource_uri": "/api/v1/organizations/1/"}

This is very similar to django tastypie manytomany field POST json error, but I am not using a through attribute on my ManyToMany relationship.

Answer 1

The problem turned out to be the validation method. Using FormValidation means that a uri like /api/v1/organizations/1/ won’t validate as a ForeignKey for the Django ORM. Using a custom validation instead fixes the issue.

Many Bothans died to bring us this information.