Calculate retained member counts for each month

apiserver/apiserver/api/management/commands/run_daily.py

@@ -24,6 +24,9 @@ class Command(BaseCommand):
         count = self.tally_active_members()
         self.stdout.write('Tallied {} active members'.format(count))
 
+        count = utils_stats.calc_retain_counts()
+        self.stdout.write('Tallied {} retained members'.format(count))
+
         utils_stats.changed_card()
         self.stdout.write('Updated card change time')
 

apiserver/apiserver/api/models.py

@@ -138,6 +138,8 @@ class StatsMemberCount(models.Model):
 class StatsSignupCount(models.Model):
     month = models.DateField()
     signup_count = models.IntegerField()
+    retain_count = models.IntegerField(default=0)
+    vetted_count = models.IntegerField(default=0)
 
 class HistoryIndex(models.Model):
     content_type = models.ForeignKey(ContentType, null=True, on_delete=models.SET_NULL)

apiserver/apiserver/api/utils_stats.py

@@ -75,6 +75,28 @@ def calc_signup_counts():
 
     return num_new_members
 
+def calc_retain_counts():
+    signup_counts = models.StatsSignupCount.objects.all()
+
+    all_members = models.Member.objects
+    active_members = all_members.filter(paused_date__isnull=True)
+    vetted_members = all_members.filter(vetted_date__isnull=False)
+
+    for entry in signup_counts:
+        date = entry.month
+        active_new_members = active_members.filter(
+            application_date__month=date.month, application_date__year=date.year
+        )
+        vetted_new_members = vetted_members.filter(
+            application_date__month=date.month, application_date__year=date.year
+        )
+
+        entry.retain_count = active_new_members.count()
+        entry.vetted_count = vetted_new_members.count()
+        entry.save()
+
+    return active_members.count()
+
 def check_minecraft_server():
     if secrets.MINECRAFT:
         url = 'https://api.minetools.eu/ping/' + secrets.MINECRAFT

apiserver/apiserver/api/views.py

@@ -393,9 +393,12 @@ class MemberCountViewSet(Base, List):
 
 class SignupCountViewSet(Base, List):
     pagination_class = None
-    queryset = models.StatsSignupCount.objects.order_by('-month')[:16][::-1]
     serializer_class = serializers.SignupCountSerializer
 
+    def get_queryset(self):
+        # have to use method as slicing breaks makemigrations
+        return models.StatsSignupCount.objects.order_by('-month')[:16][::-1]
+
 
 class BackupView(views.APIView):
     def get(self, request):