How to group two same values and get value from other field in django, DRF-CodePudding

I am struggling with grouping two same field values and displaying their related values in one response.

models.py:

class Book(models.Model):
    user = models.ForeignKey(User, on_delete = models.CASCADE, null = True, blank = True)
    image = models.ImageField(default = "Nana.jpg", upload_to = 'images/', null = True, blank = True)
    title = models.CharField(max_length = 150, unique = True)
    author = models.CharField(max_length = 100)
    category = models.CharField(max_length = 100)
    description = models.TextField(max_length = 5000, null = True, blank = True)
    published_date = models.DateField(null = True, blank = True)
    language = models.CharField(max_length = 100, null = True, blank = True, default = "Not selected")
    read_book_count = models.IntegerField(default = 0)


    def __str__(self):
        return self.title

Views.py:

class BookAuthors(APIView):

def get(self, request):
    author = Book.objects.all()
    serializer = AuthorSerializer(author, many = True)
    return Response(serializer.data)

serializers.py

class AuthorSerializer(serializers.ModelSerializer):
    class Meta:
        model = Book
        fields = ['title', 'author']

urls.py

path('library/api/authors/', views.BookAuthors.as_view()),

I want to combine author Homer and his two titles in same place not to be separated.

CodePudding user response：

You need to use the query with distinct authors and change your serializer.

Views.py

class BookAuthors(APIView):

def get(self, request):
    author = Book.objects.distinct('author')
    serializer = AuthorSerializer(author, many = True)
    return Response(serializer.data)

serializers.py

class AuthorSerializer(serializers.ModelSerializer):
    titles = serializers.SerializerMethodField()

    class Meta:
        model = Book
        fields = ['author', 'titles']

    def get_titles(self, book):
        return list(Book.objects.filter(author=book.author).values_list('title', flat=True))

Output will be like this

[
    ...
    
    {
        "author": "author1",
         "titles": ["title1", "title2"]

    },

    ...

]