I'm putting this here because it's probably user error, not an issue with the repo. I'm new to DRF, so this might be something really obvious.

Calling StringRelatedField removes these fields from "relationships". If I disable djangorestframework-jsonapi, the standard API shows the string values correctly.

models.py

...
class Model_D(models.Model):
 model_a = models.ManyToManyField(Model_A)
 model_b = models.ForeignKey(Model_B, on_delete=models.CASCADE)
 model_c = models.ForeignKey(Model_C, on_delete=models.CASCADE)
...

serializers.py

from rest_framework_json_api import serializers
...
class Model_DSerializer(serializers.ModelSerializer):
 ...
 model_a = serializers.StringRelatedField(many=True)
 model_b = serializers.StringRelatedField()
 model_c = serializers.StringRelatedField()
 class Meta:
 model = Episode
 fields = [
 "model_a",
 "model_b",
 "model_c",
 ]

I've tried changing to_representation() in ModelDSerializer, instead of using StringRelatedField():

 def to_representation(self, obj):
 return {
 ...
 "model_a": str(obj.model_a),
 "model_b": str(obj.model_b),
 "model_c": str(obj.model_c),
 ...
 }

For the ForeignKey fields, this replaced the data dict (type, id) with just the string value. It didn't do anything for the ManyToManyField.

I really like this package but I might not be able to use it (I don't want the ManyToMany primary keys visible in the API).

Note: the models are in four different apps, if that affects anything. They all have def __str__(self): set up correctly.