# Convert Django Validation Errors to DRF compatible Errors

While working with Django+Django Rest Framework, you might have come up in a problem that occurrence of Errors/ValidationErrors from Django Model or some internals will not response a valid `json` your API consumer was expecting.

For example:
Errors/ValidationErrors from Django Model or some internals will output something like


![django-error-debug-mode-example.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1646840079461/d5SrIsvNT.png)

This looks so ugly (on debug mode only!),  but with `DEBUG=False` as well, you will get something like


![500-error-example.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1646840429795/-ujo5wyau.png)


So, let's create up a custom exception handler for Django Rest Framework which will catch exceptions from those above mentioned scenarios and convert them to something much more prettier which can be easily transformed to `json`  



```py
from django.core.exceptions import NON_FIELD_ERRORS as DJ_NON_FIELD_ERRORS
from django.core.exceptions import ValidationError as DjValidationError
from rest_framework.exceptions import ValidationError as DRFValidationError
from rest_framework.views import api_settings
from rest_framework.views import exception_handler as drf_exception_handler

DRF_NON_FIELD_ERRORS = api_settings.NON_FIELD_ERRORS_KEY


def handle(exc, context):
    # translate django validation error which ...
    # .. causes HTTP 500 status ==> DRF validation which will cause 400 HTTP status
    if isinstance(exc, DjValidationError):
        data = exc.message_dict
        if DJ_NON_FIELD_ERRORS in data:
            data[DRF_NON_FIELD_ERRORS] = data[DJ_NON_FIELD_ERRORS]
            del data[DJ_NON_FIELD_ERRORS]

        exc = DRFValidationError(detail=data)

    return drf_exception_handler(exc, context)

``` 

and add this exception handler function as your default exception handler on django rest framework settings on your `settings.py` file

```py
REST_FRAMEWORK = {
     # .....
    'EXCEPTION_HANDLER': 'path_to_your_exception_hander'
     # ...
}
```


Now, the internal Django validation error that you raise from models or anywhere maybe will look like this;

![error-400-bad-request.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1646840847549/3BFL9mI8f.png)


Tested on
- Django(3.0.3) and Django Rest Framework(3.11.0)
- Django(4.0.2) and Django Rest Framework(3.13.1)