text: from django.contrib.auth import get_user_model
  from django.urls import reverse
  from django.test import TestCase
  
  from rest_framework.test import APIClient
  from rest_framework import status
  
  from core.models import Recipe, Tag, Ingredient
  
  from recipe.serializers import RecipeSerializer, RecipeDetailSerializer
  
  RECIPE_URL = reverse('recipe:recipe-list')
  
  
  def detail_url(recipe_id):
      """Return recipe detail url"""
      return reverse('recipe:recipe-detail', args=[recipe_id])
  
  
  def sample_tag(user, name="main course"):
      """return a sample tag"""
      return Tag.objects.create(user=user, name=name)
  
  
  def sample_ingredient(user, name="cineman"):
      """retrurn samole 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 PublicRecipeApiTest(TestCase):
      """tests for unauthorized users"""
  
      def setUp(self):
          self.client = APIClient()
  
      def test_login_required(self):
          """test login is required"""
          res = self.client.get(RECIPE_URL)
  
          self.assertEqual(res.status_code, status.HTTP_401_UNAUTHORIZED)
  
  
  class PrivateRecipeApiTest(TestCase):
      """tests for recipe api for authorized users"""
  
      def setUp(self):
          self.client = APIClient()
          self.user = get_user_model().objects.create_user(
              "test@gmail.com",
              "testpass"
          )
  
          self.client.force_authenticate(self.user)
  
      def test_retrieve_recipes(self):
          """test retrieving list of recipes"""
          sample_recipe(self.user)
          sample_recipe(self.user)
  
          res = self.client.get(RECIPE_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_recipe_limited_to_user(self):
          """Test retrieving recipes for user"""
          user2 = get_user_model().objects.create_user(
              "test@test.com",
              "pass123"
          )
          sample_recipe(user=user2)
          sample_recipe(user=self.user)
  
          res = self.client.get(RECIPE_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))  # adding a tag object to a
          # recipe object tags is the field in rceipe model
          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': 'Chocalte CheesCake',
              'time_minutes': 30,
              'price': 5.00
          }
          res = self.client.post(RECIPE_URL, payload)
          # return a dictionary data
  
          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))
              # getattr(recipe, key)=recipe.value of key
  
      def test_recipe_with_tags(self):
          """Test creating a recipe with tags"""
          tag1  = sample_tag(user=self.user, name='Vegan')
          tag2 = sample_tag(user=self.user, name='Desert')
          payload = {
              'title': 'Avacado Lime CheeseCake',
              'tags': [tag1.id, tag2.id],
              'time_minutes': 60,
              'price': 20.00
          }
          res = self.client.post(RECIPE_URL, payload)
  
          self.assertEqual(res.status_code, status.HTTP_201_CREATED)
          recipe = Recipe.objects.get(id=res.data['id'])
          tags = recipe.tags.all()  # returns all tags of the recipe
          self.assertEqual(tags.count(), 2)
          self.assertIn(tag1, tags)
          self.assertIn(tag2, tags)
  
      def test_recipe_with_ingredients(self):
          """Test creating a recipe with ingredients"""
          ingredient1 = sample_ingredient(user=self.user, name="salt")
          ingredient2 = sample_ingredient(user=self.user, name="sugar")
          payload = {
              'title': "Thai prawn red curry",
              'ingredients': [ingredient1.id, ingredient2.id],
              'time_minutes': 30,
              'price': 20.00
          }
          res = self.client.post(RECIPE_URL, payload)
  
          self.assertEqual(res.status_code, status.HTTP_201_CREATED)
          recipe = Recipe.objects.get(id=res.data['id'])
          ingredients = recipe.ingredients.all()  # returns all tags of the recipe
          self.assertEqual(ingredients.count(), 2)
          self.assertIn(ingredient1, ingredients)
          self.assertIn(ingredient2, ingredients)
  