Format ValidationError in Serializer - json

Question

DjangoRestFramework seems to handle errors with a variety of ways. The ValidationError in the serializer class does not consistently return JSON the same.
Current response includes a JSON list/object string:
{"detail":["Unable to log in with provided credentials."]}
Looking to achieve:
{"detail":"Unable to log in with provided credentials."}
I realize that this response is a result of default functions. However, I've overridden the validate function:
class AuthCustomTokenSerializer(serializers.Serializer):
username = serializers.CharField(write_only=True)
password = serializers.CharField(write_only=True)
token = serializers.CharField(read_only=True)
def validate(self, validated_data):
username = validated_data.get('username')
password = validated_data.get('password')
# raise serializers.ValidationError({'detail': 'Unable to log in with provided credentials.'})
if username and password:
user = authenticate(phone_number=username, password=password)
try:
if UserInfo.objects.get(phone_number=username):
userinfo = UserInfo.objects.get(phone_number=username)
user = User.objects.filter(user=userinfo.user, password=password).latest('date_joined')
if user:
if user.is_active:
validated_data['user'] = user
return validated_data
else:
raise serializers.ValidationError({"detail": "User account disabled."})
except UserInfo.DoesNotExist:
try:
user = User.objects.filter(email=username, password=password).latest('date_joined')
if user.is_active:
validated_data['user'] = user
return validated_data
except User.DoesNotExist:
#raise serializers.ValidationError("s")
raise serializers.ValidationError({'detail': 'Unable to log in with provided credentials.'})
else:
raise serializers.ValidationError({"detail" : "Must include username and password."})
class Meta:
model = Token
fields = ("username", "password", "token")
I've tried adding a custom exception handler:
from rest_framework.views import exception_handler
def custom_exception_handler(exc, context):
# Call REST framework's default exception handler first,
# to get the standard error response.
response = exception_handler(exc, context)
# Now add the HTTP status code to the response.
if response is not None:
response.data['status_code'] = response.status_code
return response
views.py: if serializer.is_valid(raise_exception=True):
However, that only appends the currently raised error:
{"detail":["Unable to log in with provided credentials."],"status_code":400}
How should I use change the format of the returning text?
It only returns the JSON like this for this particular serializer within the validate function.
I've also looked into formatting the non_field_errors template, but it works with all my other serializers e.g:
{"detail": "Account exists with email address."}

Answer 1

Maybe you should try overriding json renderer class and hook up a custom one, where you can check for status code and detail key in response data, then re-format the value appropriately.
I never tried that, so I can't give you the exact codebase, but this is the only approach I can think of to have consistent response.