How do you mock external API calls in Django tests? Django टेस्ट में बाहरी API कॉल्स को कैसे मॉक करें?

Tests that call a real external API during a test run are slow, flaky (network issues, rate limits), and non-deterministic, so external calls should be replaced with mocks that return controlled, predictable responses. Python's built-in unittest.mock.patch replaces the function or method making the external call for the duration of the test.

For libraries like requests, responses or requests-mock are commonly used to intercept and stub HTTP calls at the transport level, verifying both that the correct request was made and that the code correctly handles the mocked response, including error cases like timeouts or 500 responses that would be hard to trigger against a real API.

from unittest.mock import patch

class PaymentServiceTest(TestCase):
    @patch('payments.services.requests.post')
    def test_charge_success(self, mock_post):
        mock_post.return_value.status_code = 200
        mock_post.return_value.json.return_value = {"status": "success"}

        result = PaymentService().charge(amount=100)
        self.assertTrue(result.success)