Django Rest Framework External API Mock. You must install requests_mock using pip like `pip install requests_mock`

CreateTransporterAPITest.py

# In your test classes. For example OnboardTransporterAPITest.py
=================================================================
import requests_mock
from rest_framework import status
from django.urls import include, path, reverse
from rest_framework.test import APITestCase, URLPatternsTestCase


@requests_mock.Mocker()
class OnboardTransporterAPITest(APITestCase, URLPatternsTestCase):

    urlpatterns = [
        path("v2/vehicle", include('vehicle_type.urls'))
    ]

    def test_transporter_can_be_onboarded_and_user_be_created(self, requests_mock):

        # Begin by mocking outside APIs
        expected_response = '{"status": "Success","code": 201,"message": "Registration Successful","data": [{"id": 37,"names": "Test User","email": "testuser@amtruck.com","phone_number": "+25470052355"}]}'
        
        # Each time the app calls following URL with POST method, return expected response
        # It does not have to go outside to the internet.
        requests_mock.post(
            "https://dev.api.domain.co/v2/auth/user/register/", text=expected_response)

        payload = '{"name": "John Doe", "email": "johndoe@amitruck.com", "phone_number": "2547571692810"}'
        response = self.client.post(
            reverse('transporter_create'), payload, content_type="application/json")

        assert response.status_code == status.HTTP_201_CREATED
        assert response.data["status"] == "success"

        transporter_data = response.data["data"][0]

        assert transporter_data["id"] == 37
        assert transporter_data["names"] == "Test User"

CreateTransporterView.py

# in your view example CreateTransporterView.py
# ----------------------------------------------
import requests
from rest_framework import status


class CreateTransporterView(BaseView):

    def post(self, request):

        # First register the transporter as the user
        response = requests.post(
            "https://dev.api.domain.co/v2/auth/user/register/")
        transporter_user = response.json()

        response = {
            "code": status.HTTP_201_CREATED,
            "status": "success",
            "message": "Transporter onboarded",
            "data": [transporter_user["data"][0]]
        }

        return self.response(response, response["code"])