Include Specific Foreign Keys in DRF Serializer - django

Question

Here's two simple models to use as an example:
class Author(models.Model):
name = models.CharField(blank=True, max_length=50)
age = models.IntegerField(null=True, )
class Book(models.Model):
title = models.CharField(max_length=100)
author = models.ForeignKey(Author)
date = models.DateField()
Now what I'd like to do, is create a view for Book that pulls in one of the values from Author using the Django Rest Framework. Here's an example ModelSerializer:
class BookMetaSerializer(serializers.ModelSerializer):
class Meta:
model = Book
fields = ('title','date','author__name',)
The trouble is that one can't access the fields of a foriegn key in the DRF like I gave above author__name. I haven't been able to figure out how to do this based on the documentation. All help is appreciated, thanks!

Answer 1

You can define author_name field with source argument to get the name of an author.
From the DRF docs on source argument:
The name of the attribute that will be used to populate the field. May
be a method that only takes a self argument, such as
URLField('get_absolute_url'), or may use dotted notation to traverse
attributes, such as EmailField(source='user.email').
Final Code:
class BookMetaSerializer(serializers.ModelSerializer):
# use dotted notation to traverse to 'name' attribute
author_name = serializers.CharField(source='author.name', read_only=True)
class Meta:
model = Book
fields = ('title','date','author_name',)