How to change serializer field name when validation error is triggered - django

Question

I need to change the view of the error displayed when I validate the field.
serializer.py
class ElementCommonInfoSerializer(serializers.ModelSerializer):
self_description = serializers.CharField(required=False, allow_null=True,
validators=[RegexValidator(regex=r'^[a-zA-Z0-9,.!? -/*()]*$',
message='The system detected that the data is not in English. '
'Please correct the error and try again.')]
)
....
class Meta:
model = Elements
fields = ('self_description',......)
This error is displayed
{
"self_description": [
"The system detected that the data is not in English. Please correct the error and try again."
]
}
The key of error dict is field name - self_description. For FE I need to send another format like:
{
"general_errors": [
"The system detected that the data is not in English. Please correct the error and try again."
]
}
How to change this?

Answer 1

One way this could be achieved is via custom exception handler
from copy import deepcopy
from rest_framework.views import exception_handler
def genelalizing_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 'self_description' in response.data:
data = deepcopy(response.data)
general_errors = data.pop('self_description')
data['general_errors'] = general_errors
response.data = data
return response
in settings
REST_FRAMEWORK = {
'EXCEPTION_HANDLER': 'my_project.my_app.utils. genelalizing_exception_handler'
}

Answer 2

Another solution is to rewrite the validate method.
def validate(self, data):
self_description = str((data['self_description']))
analyst_notes = str((data['analyst_notes']))
if re.match(r'^[a-zA-Z0-9,.!? -/*()]*$', self_description) or re.match(r'^[a-zA-Z0-9,.!? -/*()]*$', analyst_notes):
raise serializers.ValidationError({
"general_errors": [
"The system detected that the data is not in English. Please correct the error and try again."
]
})
return data

Answer 3

The solution is very simple.
you can rename the key field by using serializer method (source attribute)
below you can find an example code.
class QuestionSerializer(serializers.ModelSerializer):
question_importance = serializers.IntegerField(source='importance')
question_importance = serializers.IntegerField(required=False)
class Meta:
model = create_question
fields = ('id','question_importance','complexity','active')
Above you can see I have an importance field which is present in django model But here I renamed this field to question_importance by using source attribute .
In your case it will be like below,
class ElementCommonInfoSerializer(serializers.ModelSerializer):
general_errors = serializer.CharField(source="self_description")
general_error = serializers.CharField(required=False, allow_null=True,
validators=[])
class Meta:
model = Elements
fields = ('general_error',......)