text: from django.test import TestCase
  from django.contrib.auth import get_user_model
  from django.urls import reverse
  
  from rest_framework.test import APIClient
  from rest_framework import status
  
  
  CREATE_USER_URL = reverse('user:create')
  TOKEN_URL = reverse('user:token')
  ME_URL = reverse('user:me')
  
  
  def create_user(**params):
      return get_user_model().objects.create_user(**params)
  
  
  class PublicUserApiTests(TestCase):
      """test the users API (public)"""
  
      def setUp(self):
          self.client = APIClient()
  
      def test_create_valid_user_success(self):
          """test creating user with valid payload is successful"""
          payload = {
              'email': 'test@appdev.com',
              'password': 'testpass',
              'name': 'Test Name'
          }
          res = self.client.post(CREATE_USER_URL, payload)
  
          self.assertEqual(res.status_code, status.HTTP_201_CREATED)
          user = get_user_model().objects.get(**res.data)
          self.assertTrue(user.check_password(payload['password']))
          self.assertNotIn('password', res.data)
  
      def test_user_exists(self):
          """test creating user that already exists fails"""
          payload = {
              'email': 'test@appdev.com',
              'password': 'testpass'
          }
          create_user(**payload)
  
          res = self.client.post(CREATE_USER_URL, payload)
          self.assertIn('email', res.data)
          self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
  
      def test_password_too_short(self):
          """test that the password must be more than 5 characters"""
          payload = {
              'email': 'test@appdev.com',
              'password': 'pw'
          }
  
          # create_user(**payload)
          res = self.client.post(CREATE_USER_URL, payload)
          self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
          user_exists = get_user_model().objects.filter(
              email=payload['email']
          ).exists()
          self.assertFalse(user_exists)
  
      def test_create_token_for_user(self):
          """test that a token is created for user"""
          payload = {
              'email': 'test@appdev.com',
              'password': 'testpass',
              'name': 'Test Name'
          }
          create_user(**payload)
          res = self.client.post(TOKEN_URL, payload)
  
          self.assertIn('token', res.data)
          self.assertEqual(res.status_code, status.HTTP_200_OK)
  
      def test_create_token_invalid_credentials(self):
          """test that token is not created if invalid credentials are given"""
          create_user(email='test@appdev.com', password='testpass')
          payload = {
              'email': 'testdev@appdev.com',
              'password': 'wrongtestpass'
          }
          res = self.client.post(TOKEN_URL, payload)
  
          self.assertNotIn('token', res.data)
          self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
  
      def test_create_token_no_user(self):
          """test that token is not created if user doesn't exist"""
          payload = {
              'email': 'testdev@appdev.com',
              'password': 'testpass'
          }
          res = self.client.post(TOKEN_URL, payload)
  
          self.assertNotIn('token', res.data)
          self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
  
      def test_create_token_missing_field(self):
          """test that email and password are required"""
          payload = {
              'email': 'one',
              'password': ''
          }
          res = self.client.post(TOKEN_URL, payload)
  
          self.assertNotIn('token', res.data)
          self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
  
      def test_retrieve_user_unauthorized(self):
          """test that authentication is required for users"""
          res = self.client.get(ME_URL)
  
          self.assertEqual(res.status_code, status.HTTP_401_UNAUTHORIZED)
  
  
  class PrivateUserApiTests(TestCase):
      """test api that require authentication"""
  
      def setUp(self):
          self.user = create_user(
              email='test@appdev.com',
              password='testpass',
              name='name'
          )
          self.client = APIClient()
          self.client.force_authenticate(user=self.user)
  
      def test_retrieve_profile_success(self):
          """test retrieving profile for logged in used"""
          res = self.client.get(ME_URL)
  
          self.assertEqual(res.status_code, status.HTTP_200_OK)
          self.assertEqual(res.data, {
              'name': self.user.name,
              'email': self.user.email
          })
  
      def test_post_me_not_allowed(self):
          """test that post is not allowed on the me url"""
          res = self.client.post(ME_URL, {})
  
          self.assertEqual(res.status_code, status.HTTP_405_METHOD_NOT_ALLOWED)
  
      def test_update_user_profile(self):
          """test updating the user profile for authenticated user"""
          payload = {'name': 'new_name',
                     'password': 'newpassword123'}
  
          res = self.client.patch(ME_URL, payload)
  
          self.user.refresh_from_db()
          self.assertEqual(self.user.name, payload['name'])
          self.assertTrue(self.user.check_password(payload['password']))
          self.assertEqual(res.status_code, status.HTTP_200_OK)
  