[FIXED] Get object by id of OneToOne related object in DRF

Issue

I have Progress model which relates with Deck model by OneToOne relation. I want to get Progress object from API by passing deck_id to 'http://localhost/api/v1/progress/deck_id/' endpoint. How I can do this? Or may be should I consider other implementations of retrieving Progress object? Also I want all CRUD functions with this model.

class Deck(models.Model):
        name = models.CharField(max_length=70)
        owner = models.ForeignKey(
            CustomUser,
            on_delete=models.CASCADE,
            related_name='decks',
        ) 

class Progress(models.Model):
        deck = models.OneToOneField(Deck)
        progress = models.JSONField(
            null=True
        )

class ProgressViewSet(viewsets.ModelViewSet):
    queryset = Progress.objects.all()
    serializer_class = ProgressSerializer
    permission_classes = (OwnerOrAdminProgress,)
    lookup_field = 'id'
    http_method_names = ['get', 'post', 'patch', 'delete']


class ProgressSerializer(serializers.ModelSerializer):
    progress = serializers.JSONField()

    class Meta:
        model = Progress
        fields = ('id', 'deck', 'progress')


router_v1 = routers.DefaultRouter()
router_v1.register('v1/decks', DeckViewSet, basename='decks')
router_v1.register('v1/progress', ProgressViewSet, basename='progress')

urlpatterns = [
    path('', include(router_v1.urls)),
]

Solution

We can add action to ProgressViewSet:

@action(
        detail=False,
        permission_classes=[OwnerOrAdminProgressDeck],
        methods=['get'],
        url_path='deck/(?P<deck_id>[^/.]+)'
    )
    def progress_by_deck(self, request, deck_id=None):
        try:
            deck = Deck.objects.get(id=deck_id)
            progress = Progress.objects.get(deck=deck)
            serializer = ProgressSerializer(progress)
            return Response(serializer.data)
        except (Deck.DoesNotExist, Progress.DoesNotExist):
            return Response(
                {"error": "Progress not found for the given deck_id"},
                status=status.HTTP_404_NOT_FOUND,
            )

Answered By - CarloDiPalma