django rest framework - DRF 3.0: UniqueTogetherValidator with a read-only field -

in process of upgrading django rest framework 3.0 2.4.4 , want have read-only user field, failing because 'user' being required uniquetogethervalidator (i think)

i have model (excuse typos, simplified , code works fine irl):

class examplemodel(models.model):     some_attr = models.positivesmallintegerfield()     other_attr = models.positivesmallintegerfield()     user = models.foreignkey(user)      class meta:         unique_together = ('some_attr', 'other_attr', 'user') 

viewset:

class exampleviewset(viewsets.modelviewset):     queryset = examplemodel.objects.all()     serializer_class = exampleserializer      def perform_create(self, serializer):         serializer.save(user=self.request.user)      def perform_update(self, serializer):         serializer.save(user=self.request.user) 

serializer:

class exampleserializer(serializers.modelserializer):     user = userserializer(read_only=true)      class meta:         model = examplemodel 

now, keep getting errors saying: {"user":["this field required."]}, not case before. in different example same basic problem, assertion error may not set both 'read_only' , 'required' though not setting user required.

i receive same error regardless if add required=false user attribute in serializer, or if add user the excluded fields in serializer's meta.

when use handy new serializer printing, see:

class meta:     validators = [uniquetogethervalidator(queryset=examplemodel.objects.all(), fields=('user', 'some_attr', 'other_attr'))] 

which gets automatically added based on model's unique_together. if explicitly overwrite , not include 'user' in fields uniquetogethervalidator works before.

is intended consequence of 3.0 update? seems me adding request.user in perform_create / perform_update standard drf procedure demonstrated in tutorial. realize not having new validation means failing @ db level instead, , new validation gives better error messages, but

is there solution other override validation every serializer issue?

thanks in advance help!

this a known issue in process of addressing within django rest framework. of right now, there note in documentation uniquetogthervalidator says

note: uniquetogethervalidation class imposes implicit constraint fields applies treated required. fields default values exception supply value when omitted user input.

this explains why seeing error because field required, though explicitly settings read_only=true. may want currentuserdefault class, may suit needs while avoiding issue uniquetogethervalidator.

class exampleserializer(serializers.modelserializer):     user = userserializer(         read_only=true         default=serializers.currentuserdefault()     )      class meta:         model = examplemodel 

this should same thing perform_create , perform_update hooks.