How to get the id using a get_context_data? - django

Question

I would like to get the total amount of followers attached to the models using in models :
class Project(models.Model):
owner = models.ForeignKey(User, related_name='project_created_by', on_delete=models.CASCADE)
name = models.CharField(max_length=100)
description = models.TextField(max_length=150, blank=True, null=True)
followers = models.ManyToManyField(settings.AUTH_USER_MODEL, related_name='followers', blank=True)
created = models.DateTimeField(auto_now_add=True)
last_modefied = models.DateTimeField(auto_now=True)
def __str__(self):
return self.name
Here is the class
class ProjectListView(ListView):
template_name = 'projectmanagement/project.html'
context_object_name = 'projects'
def get_queryset(self):
queryset = Project.objects.filter(owner=self.request.user).order_by("name")
return queryset
def get_context_data(self, *args, **kwargs):
context = super(ProjectListView, self).get_context_data(*args, **kwargs)
project = Project.objects.get(pk=12) <-- HERE -->
context['followers'] = project.followers.filter(followers=project).count()
return context

Answer 1

You can .annotate(..) [Django-doc] the queryset of your Product with the number of followers:
from django.db.models import Count
class ProjectListView(ListView):
model = Project
template_name = 'projectmanagement/project.html'
context_object_name = 'projects'
def get_queryset(self):
return super().get_queryset().annotate(
nfollowers=Count('followers')
).filter(
owner=self.request.user
).order_by('name')
Now all projects in the context data will have an extra attribute nfollowers with the number of followers.
You can thus render this for example with:
{% for project in projects %}
{{ project.name }}, followers: {{ project.nfollowers }}<br>
{% endfor %}