Django:一个函数，两个基于类的视图

Question

我目前正在努力为get_survey_state(self, context)找到更好的解决方案。 它在两种CBV中，我认为有比我更好的解决方案。你能告诉我吗？

views.py

class SurveyExpectations(AdminPermissionRequiredMixin, TemplateView):
template_name = 'admin/surveys/expectations.html'
def get_survey_state(self, context):
survey = self.request.event.surveys.active_pre_event().first()
answers = Answer.objects.filter(question__survey=survey).exists()
context['survey_is_active'] = survey
context['answers_exist'] = answers
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
self.get_survey_state(context)
context['questions_and_answers'] = self.request.event.surveys.get_results(
settings.SURVEY_PRE_EVENT
)
return context
class SurveyFeedback(AdminPermissionRequiredMixin, TemplateView):
template_name = 'admin/surveys/feedback.html'
def get_net_promoter_score(self) -> float:
[...]
return netpromoterscore(scores)
def get_average_age(self) -> int:
[...]
return int(answers['avg']) if answers['avg'] else None
def get_survey_state(self, context):
survey = self.request.event.surveys.active_post_event().first()
answers = Answer.objects.filter(question__survey=survey).exists()
context['survey_is_active'] = survey
context['answers_exist'] = answers
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
self.get_survey_state(context)
context['questions_and_answers'] = self.request.event.surveys.get_results(
settings.SURVEY_POST_EVENT
)
context['netpromoterscore'] = self.get_net_promoter_score()
context['average_age'] = self.get_average_age()
return context

models.py

class SurveyQuerySet(models.QuerySet):
def active_pre_event(self):
return self.filter(is_active=True, template=settings.SURVEY_PRE_EVENT)
def active_post_event(self):
return self.filter(is_active=True, template=settings.SURVEY_POST_EVENT)
def get_results(self, template):
return (
self.get(template=template)
.questions.exclude(focus=QuestionFocus.EMAIL)
.all()
.prefetch_related('answers')
)
class Survey(TimeStampedModel):
id = models.UUIDField([...])
is_active = models.BooleanField([...])
template = models.CharField([...])
objects = SurveyQuerySet.as_manager()

Answer 1

您可以使用类继承。创建一个基类(派生自模板视图(，在其中定义所有常用功能。

然后，您可以从基类派生更多视图，基类将继承所有功能。

get_survey_state使用方法self.get_survey()允许在派生视图中使用不同的检索方法。

class BaseSurveyView(TemplateView):
def get_survey_state(self, context):
survey = self.get_survey()
answers = Answer.objects.filter(question__survey=survey).exists()
context['survey_is_active'] = survey
context['answers_exist'] = answers
def get_survey(self):
raise NotImplementedError

class SurveyExpectations(AdminPermissionRequiredMixin, BaseSurveyView):
template_name = 'admin/surveys/expectations.html'
def get_survey(self):
return self.request.event.surveys.active_pre_event().first()
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
self.get_survey_state(context)
context['questions_and_answers'] = self.request.event.surveys.get_results(
settings.SURVEY_PRE_EVENT
)
return context
class SurveyFeedback(AdminPermissionRequiredMixin, BaseSurveyView):
template_name = 'admin/surveys/feedback.html'
def get_survey(self):
return self.request.event.surveys.active_post_event().first()
def get_net_promoter_score(self) -> float:
[...]
return netpromoterscore(scores)
def get_average_age(self) -> int:
[...]
return int(answers['avg']) if answers['avg'] else None
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
self.get_survey_state(context)
context['questions_and_answers'] = self.request.event.surveys.get_results(
settings.SURVEY_POST_EVENT
)
context['netpromoterscore'] = self.get_net_promoter_score()
context['average_age'] = self.get_average_age()
return context