text: from django.contrib.auth import get_user_model
  from django.urls import reverse
  from django.test import TestCase
  
  from rest_framework import status
  from rest_framework.test import APIClient
  
  from core.models import Ingredient
  
  from recipe.serializers import IngredientSerializer
  
  
  INGREDIENTS_URL = reverse("recipe:ingredient-list")
  
  
  class PublicIngredientsApiTests(TestCase):
      """Test the publically available ingredients API"""
  
      def setUp(self):
          self.client = APIClient()
  
      def test_login_required(self):
          """Test that login is required to access this endpoint"""
          res = self.client.get(INGREDIENTS_URL)
  
          self.assertEqual(res.status_code, status.HTTP_401_UNAUTHORIZED)
  
  
  class PrivateIngredientsAPITests(TestCase):
      """Test ingredients can be retrieved by authorized user"""
  
      def setUp(self):
          self.client = APIClient()
          self.user = get_user_model().objects.create_user(
              "test@londonappdev.com", "testpass"
          )
          self.client.force_authenticate(self.user)
  
      def test_retrieve_ingredient_list(self):
          """Test retrieving a list of ingredients"""
          Ingredient.objects.create(user=self.user, name="kale")
          Ingredient.objects.create(user=self.user, name="Salt")
  
          res = self.client.get(INGREDIENTS_URL)
  
          ingredients = Ingredient.objects.all().order_by("-name")
          serializer = IngredientSerializer(ingredients, many=True)
          self.assertEqual(res.status_code, status.HTTP_200_OK)
          self.assertEqual(res.data, serializer.data)
  
      def test_ingredients_limited_to_user(self):
          """Test that only ingredients for authenticated user are returned"""
          user2 = get_user_model().objects.create_user(
              "other@londonappdev.com", "testpass"
          )
          Ingredient.objects.create(user=user2, name="Vinegar")
  
          ingredient = Ingredient.objects.create(user=self.user, name="Tumeric")
  
          res = self.client.get(INGREDIENTS_URL)
  
          self.assertEqual(res.status_code, status.HTTP_200_OK)
          self.assertEqual(len(res.data), 1)
          self.assertEqual(res.data[0]["name"], ingredient.name)
  
      def test_create_ingredient_successful(self):
          """Test create a new ingredient"""
          payload = {"name": "Cabbage"}
          self.client.post(INGREDIENTS_URL, payload)
  
          exists = Ingredient.objects.filter(
              user=self.user, name=payload["name"]
          ).exists()
  
          self.assertTrue(exists)
  
      def test_create_ingredient_invalid(self):
          payload = {"name": ""}
          res = self.client.post(INGREDIENTS_URL, payload)
  
          self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
  