Get Officials by year with query param year

webapp/models.py

@@ -194,6 +194,12 @@ class Occupation(models.Model):
     end_date = models.DateField(_('End date'))
     role = models.ForeignKey('Role', on_delete=models.SET_NULL, null=True)
 
+    @staticmethod
+    def occupations_by_year(year):
+        return Occupation.objects.filter(
+            end_date__gte=timezone.datetime(year, 1, 1)).filter(
+            start_date__lte=timezone.datetime(year, 12, 31))
+
     def __str__(self):
         return '{}: {} - {}'.format(self.role.name, self.start_date, self.end_date)
 
@@ -217,11 +223,12 @@ class Official(models.Model):
 
     @property
     def current_roles(self):
-        return self.role_history.all().filter(end_date__gte=timezone.now()).filter(start_date__lte=timezone.now())
+        return self.role_history.all().filter(end_date__gte=timezone.now())
 
-    @property
-    def roles_of_year(self, year):
-        return self.role_history.all().filter(end_date__gte=timezone.datetime(year, 1, 1)).filter(start_date__lte=timezone.datetime(year, 12, 31))
+    @staticmethod
+    def official_by_year(year):
+        return Official.objects.filter(
+            role_history__in=Occupation.occupations_by_year(year)).distinct()
 
     def __str__(self):
         return '{} {}'.format(self.first_name, self.last_name)

webapp/serializers.py

@@ -116,9 +116,9 @@ class OccupationSerializer(serializers.ModelSerializer):
 
 
 class ContactsSerializer(serializers.ModelSerializer):
-    current_roles = OccupationSerializer(many=True, read_only=True)
+    role_history = OccupationSerializer(many=True, read_only=True)
 
     class Meta:
         model = Official
-        fields = ('id', 'first_name', 'last_name', 'email', 'phone_number', 'current_roles')
+        fields = ('id', 'first_name', 'last_name', 'email', 'phone_number', 'role_history')
         depth = 2

webapp/views.py

@@ -112,6 +112,12 @@ class ContactsViewSet(viewsets.ReadOnlyModelViewSet):
     serializer_class = ContactsSerializer
     permission_classes = [IsAuthenticatedOrReadOnly]
 
+    def get_queryset(self):
+        year = self.request.query_params.get('year')
+        if not year:
+            return Official.official_by_year(timezone.now().year)
+        return Official.official_by_year(int(year))
+
 
 class TagsViewSet(viewsets.ReadOnlyModelViewSet):
     queryset = Tag.objects.all()