Django Rest Framework - Filter with logical and

Question

I'm using Django Rest Framework with DjangoFilterBackend to filter through Publications. Every publication can have multiple authors. My api call to filter the api for authors looks like:

/api/v1/publication/?author=1&author=2

This gives me every publication that either author 1 or author 2 has been assigned to. Instead I want to only see the publications that both have published. In other words it should be a logic and, not or.

My code is the following:

models.py

class Publication(models.Model):
    id = models.BigAutoField(primary_key=True)
    title = models.CharField(max_length=400)
    author = models.ManyToManyField(Author, blank=False)
    type = models.ForeignKey(
        Type, on_delete=models.PROTECT, null=False, default=1)
    label = models.ManyToManyField(Label, blank=True)
    date = models.DateField(blank=False, null=False)
    url = models.URLField(null=True, blank=True)
    journal = models.CharField(max_length=400, blank=True)
    bibtex = models.TextField(blank=True)
    public = models.BooleanField(default=False)
    updated = models.DateTimeField(auto_now=True)
    created = models.DateTimeField(auto_now_add=True)
    file = models.FileField(upload_to=upload_path, blank=True, null=True)

    class Meta:
        ordering = ['-date']

    def __str__(self):
        return self.title

views.py

class PublicationFilter(django_filters.FilterSet):
    author = django_filters.ModelMultipleChoiceFilter(
        queryset=Author.objects.all())

    class Meta:
        model = Publication
        fields = {
            'title': ["exact"],
            'author': ["exact"]
        }


class PublicationView(viewsets.ModelViewSet):
    queryset = Publication.objects.prefetch_related(
        'author', 'label').select_related('type')
    serializer_class = PublicationSerializer
    filter_backends = [DjangoFilterBackend,
                       SearchFilter, OrderingFilter]
    filterset_fields = ['title', 'date', 'journal', 'label', 'author']
    search_fields = ['title']
    ordering_fields = ['date', 'title']

serializers.py

class PublicationSerializer(ModelSerializer):
    type = TypeSerializer(read_only=False, many=False)
    label = LabelSerializer(read_only=False, many=True)
    author = AuthorSerializer(read_only=False, many=True)

    class Meta:
        model = Publication
        fields = ['id', 'title', 'date',
                  'url', 'journal',  'label', 'author', 'type', 'date', 'bibtex', 'file']

maciek.glowka · Answer 1 · 2022-08-19T12:09:43.333

I think if you will pass only one author field in the url query, but separate the values with a comma you will end up with a list value in the django-filter.

/api/v1/publication/?author=1,2

Than you can override filter_author method in your PublicationFilter class and build the query filter manually there.

See here under method: https://django-filter.readthedocs.io/en/stable/ref/filters.html#method

You can build the query with a help of the Q object: How to dynamically compose an OR query filter in Django?

Django Rest Framework - Filter with logical and

1 Answers1