Testing views.py

Send requests to views, analyze the response and any side effects. View tests are single source of truth for the backend and a blueprint for ui to follow on how to interact with backend

Workflow: Writing a test for a FBV

1. Create ./apps/my_app/tests/test_views.py, load pytest-django plugin:

   import pytest
   pytestmark = [pytest.mark.django_db]
   

2. Define descriptive name, load client fixture:

   def test_book_author_create_form_success(client):
   

3. Define url name, make sure it is registered in urls.py:

       from django.urls import reverse
       url = reverse('books:get_authors')
   

4. Define payload for the view

5. Assert the response and side effects:

       assert r.status_code == 200
       assert Author.objects.filter(name=payload['new_author_name']).exists()
   

Workflow: Writing a test for a CBV:

1. Name it class TestThoughtView

2. Define data fixture whole class will use:

   @pytest.fixture
   def thoughts(self):
       return f.ThoughtFactory.create_batch(22)
   

3. Define test method name: test_(http method)_(action name)_(desired outcome) Other steps are similar to FBV

4. Within method, start with url:

   url = reverse('intray:thought')
   

5. Define action:

   action = 'get-new-page'
   

6. Define payload:

   payload = reverse('intray:thought')
   

Properties: Payload types

• File:

  from django.core.files.uploadedfile import SimpleUploadedFile
  
  file = SimpleUploadedFile(
      name="notes.txt",
      content=b'Dummy content of file',
      content_type="text/plain"
  )
  payload = {
      'file': file
  }
  r = client.post(url, data=payload)
  

  views.py

  file = request.FILES.get('file')
  

• GET:

      payload = {
          'page': '1'
      }
      r = client.get(url, data=payload)
  

  views.py

  page = request.GET.get('page')
  

• POST:

      payload = {
          'new_author_name': 'Jim'
      }
      r = client.post(url, data=payload)
  

  views.py

  name = request.POST.get('new_author_name')
  

See how url changes to hit specific author

• PUT:

      url = reverse('books:author_detail', args=[author.pk])
      payload = 'name=Updated+Name'
      r = client.post(url, data=payload, content_type='application/x-www-form-urlencoded')
  

  views.py

  from django.http import QueryDict
  put_data = QueryDict(request.body)
  name = put_data.get('name')
  

• DELETE:

      url = reverse('books:author_detail', args=[author.pk])
      r = client.delete(url)
  

  views.py

  author = Author.objects.get(pk=pk).delete()
  

Properties: Assertion types

• Status code:

  assert r.status_code == 200
  

• Returned template context:

  payload = {
          'new_author_name': 'Jim'
      }
  r = client.post(url, data=payload)
  assert r.context['queryset'].filter(name='Jim').exists()
  

• Proper notification triggered:

  trigger_data = json.loads(r.headers['HX-Trigger'])
  assert trigger_data['notify']['message'] == 'Success!'
  

• DB Side effects:

  assert Author.objects.filter(name='Jim').exists()
  

Workflow: Create HttpRequest instance

1. Use rf fixture provided by pytest-django:

   test_r(rf):
       request = rf.post('no-need-to-have-url', data={'hello': 'yes'})