text: from django.contrib.auth import get_user_model
  from django.test import TestCase
  from django.urls import reverse
  
  from rest_framework import status
  from rest_framework.test import APIClient
  
  from core.models import Recipe, Tag, Ingredient
  
  from recipe.serializers import RecipeSerializer, RecipeDetailSerializer
  
  RECIPES_URL = reverse('recipe:recipe-list')
  
  # /api/recipe/recipes
  # /api/recipe/recipies/1/
  
  
  def detail_url(recipe_id):
      """Return the recipe detail URL"""
      return reverse('recipe:recipe-detail', args=[recipe_id])
  
  
  def sample_tag(user, name='Main course'):
      """Create and return a sample tag"""
      return Tag.objects.create(user=user, name=name)
  
  
  def sample_ingredient(user, name='Cinnamon'):
      """Create and return a sample ingredient"""
      return Ingredient.objects.create(user=user, name=name)
  
  
  def sample_recipe(user, **params):
      """Create and return a sample recipe"""
      defaults = {
          'title': 'Sample recipe',
          'time_minutes': 10,
          'price': 5.00
      }
      defaults.update(params)
  
      return Recipe.objects.create(user=user, **defaults)
  
  
  class PublicRecipeApiTests(TestCase):
      """Test unauthenticated recipe API access"""
  
      def setUp(self):
          self.client = APIClient()
  
      def test_auth_required(self):
          """Test that authentication is required"""
          res = self.client.get(RECIPES_URL)
  
          self.assertEqual(res.status_code, status.HTTP_401_UNAUTHORIZED)
  
  
  class PrivateRecipeApiTests(TestCase):
      """Test authenticated recipe API access"""
  
      def setUp(self):
          self.client = APIClient()
          self.user = get_user_model().objects.create_user(
              'test@whatever.com',
              'testpass'
          )
          self.client.force_authenticate(self.user)
  
      def test_retrieve_recipes(self):
          """Test retrieving a list of recipes"""
          sample_recipe(user=self.user)
          sample_recipe(user=self.user)
  
          res = self.client.get(RECIPES_URL)
  
          recipes = Recipe.objects.all().order_by('-id')
          serializer = RecipeSerializer(recipes, many=True)
  
          self.assertEqual(res.status_code, status.HTTP_200_OK)
          self.assertEqual(res.data, serializer.data)
  
      def test_recipes_limited_to_user(self):
          """Test retriving recipies for user"""
          user2 = get_user_model().objects.create_user(
              'otheruser@test.com',
              'testpass2'
          )
          sample_recipe(user=user2)
          sample_recipe(user=self.user)
  
          res = self.client.get(RECIPES_URL)
  
          recipes = Recipe.objects.filter(user=self.user)
          serializer = RecipeSerializer(recipes, many=True)
  
          self.assertEqual(res.status_code, status.HTTP_200_OK)
          self.assertEqual(len(res.data), 1)
          self.assertEqual(res.data, serializer.data)
  
      def test_view_recipe_detail(self):
          """Test viewing a recipe detail"""
          recipe = sample_recipe(user=self.user)
          recipe.tags.add(sample_tag(user=self.user))
          recipe.ingredients.add(sample_ingredient(user=self.user))
  
          url = detail_url(recipe.id)
          res = self.client.get(url)
  
          serializer = RecipeDetailSerializer(recipe)
          self.assertEqual(res.data, serializer.data)
  
      def test_create_basic_recipe(self):
          """Test creating recipe"""
          payload = {
              'title': 'Chocolate cheesecake',
              'time_minutes': 30,
              'price': 5.00
          }
          res = self.client.post(RECIPES_URL, payload)
  
          self.assertEqual(res.status_code, status.HTTP_201_CREATED)
          recipe = Recipe.objects.get(id=res.data['id'])
          for key in payload.keys():
              self.assertEqual(payload[key], getattr(recipe, key))
  
      def test_create_recipe_with_tags(self):
          """Test create a recipe with tags"""
          tag1 = sample_tag(user=self.user, name='Vegan')
          tag2 = sample_tag(user=self.user, name='Dessert')
          payload = {
              'title': 'Avocado lime cheesecake',
              'tags': [tag1.id, tag2.id],
              'time_minutes': 60,
              'price': 20.00
          }
          res = self.client.post(RECIPES_URL, payload)
  
          self.assertEqual(res.status_code, status.HTTP_201_CREATED)
          recipe = Recipe.objects.get(id=res.data['id'])
          tags = recipe.tags.all()
          self.assertEqual(tags.count(), 2)
          self.assertIn(tag1, tags)
          self.assertIn(tag2, tags)
  
      def test_create_recipe_with_ingredients(self):
          """Test creating recipe with ingredients"""
          ingredient1 = sample_ingredient(user=self.user, name='Praws')
          ingredient2 = sample_ingredient(user=self.user, name='Ginger')
          payload = {
              'title': 'Thai prawn red curry',
              'ingredients': [ingredient1.id, ingredient2.id],
              'time_minutes': 20,
              'price': 7.00
          }
          res = self.client.post(RECIPES_URL, payload)
  
          self.assertEqual(res.status_code, status.HTTP_201_CREATED)
          recipe = Recipe.objects.get(id=res.data['id'])
          ingredients = recipe.ingredients.all()
          self.assertEqual(ingredients.count(), 2)
          self.assertIn(ingredient1, ingredients)
          self.assertIn(ingredient2, ingredients)
  
      def test_partial_update_recipe(self):
          """Test updating recipe with patch"""
          recipe = sample_recipe(user=self.user)
          recipe.tags.add(sample_tag(user=self.user))
          new_tag = sample_tag(user=self.user, name='Curry')
  
          payload = {'title': 'Chicken tikka', 'tags': [new_tag.id]}
          url = detail_url(recipe.id)
          self.client.patch(url, payload)
  
          recipe.refresh_from_db()
          self.assertEqual(recipe.title, payload['title'])
          tags = recipe.tags.all()
          self.assertEqual(len(tags), 1)
          self.assertIn(new_tag, tags)
  
      def test_full_update_recipe(self):
          """Test updating a recipe with put (replaces all)"""
          recipe = sample_recipe(user=self.user)
          recipe.tags.add(sample_tag(user=self.user))
          payload = {
              'title': 'Spaghetti carbonara',
              'time_minutes': 25,
              'price': 5.00
          }
          url = detail_url(recipe.id)
          self.client.put(url, payload)
  
          recipe.refresh_from_db()
          self.assertEqual(recipe.title, payload['title'])
          self.assertEqual(recipe.time_minutes, payload['time_minutes'])
          self.assertEqual(recipe.price, payload['price'])
          tags = recipe.tags.all()
          self.assertEqual(len(tags), 0)
  