Snippet

Custom View Exception Handler Decorator for Database Errors

Python closure decorators wrap view functions to capture specific runtime exceptions like Django's `IntegrityError`. Using `functools.wraps` preserves view metadata while centralizing HTTP error response formatting.

snippet.py

python

from functools import wraps
from django.db import IntegrityError
from django.http import JsonResponse
 
def handle_database_errors(view_func):
    @wraps(view_func)
    def wrapper(request, *args, **kwargs):
        try:
            return view_func(request, *args, **kwargs)
        except IntegrityError as err:
            return JsonResponse({
                "error": "Integrity constraint violation",
                "details": str(err)
            }, status=400)
    return wrapper

django

Breakdown

def handle_database_errors(view_func):

Defines a higher-order decorator function taking a view function as argument.

@wraps(view_func)

Preserves the original view function's name, docstring, and signature.

try:

Executes the wrapped view function inside a guarded try block.

except IntegrityError as err:

Catches database integrity constraint violations (e.g., duplicate unique fields).

return JsonResponse({ ... }, status=400)

Returns a structured JSON error payload with HTTP 400 Bad Request status.

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Custom View Exception Handler Decorator for Database Errors

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