✨(api) add count mailboxes to MailDomain serializer

Return number of mailboxes of a domain in our API.

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to
 
 ### Added
 
+- ✨(api) add count mailboxes to MailDomain serializer
 - ✨(dimail) manage 'action required' status for MailDomain
 - ✨(domains) add action required status on MailDomain
 - ✨(dimail) send pending mailboxes upon domain activation

src/backend/mailbox_manager/api/client/serializers.py

@@ -56,6 +56,7 @@ class MailDomainSerializer(serializers.ModelSerializer):
     """Serialize mail domain."""
 
     abilities = serializers.SerializerMethodField(read_only=True)
+    count_mailboxes = serializers.SerializerMethodField(read_only=True)
 
     class Meta:
         model = models.MailDomain
@@ -68,6 +69,7 @@ class Meta:
             "abilities",
             "created_at",
             "updated_at",
+            "count_mailboxes",
         ]
         read_only_fields = [
             "id",
@@ -76,6 +78,7 @@ class Meta:
             "abilities",
             "created_at",
             "updated_at",
+            "count_mailboxes",
         ]
 
     def get_abilities(self, domain) -> dict:
@@ -85,6 +88,10 @@ def get_abilities(self, domain) -> dict:
             return domain.get_abilities(request.user)
         return {}
 
+    def get_count_mailboxes(self, domain) -> int:
+        """Return count of mailboxes for the domain."""
+        return domain.mailboxes.count()
+
     def create(self, validated_data):
         """
         Override create function to fire a request to dimail upon domain creation.

src/backend/mailbox_manager/tests/api/mail_domain/test_api_mail_domains_create.py

@@ -114,6 +114,7 @@ def test_api_mail_domains__create_authenticated():
         "created_at": domain.created_at.isoformat().replace("+00:00", "Z"),
         "updated_at": domain.updated_at.isoformat().replace("+00:00", "Z"),
         "abilities": domain.get_abilities(user),
+        "count_mailboxes": 0,
     }
 
     # a new domain with status "pending" is created and authenticated user is the owner
@@ -185,6 +186,7 @@ def test_api_mail_domains__create_authenticated__dimail_failure():
         "created_at": domain.created_at.isoformat().replace("+00:00", "Z"),
         "updated_at": domain.updated_at.isoformat().replace("+00:00", "Z"),
         "abilities": domain.get_abilities(user),
+        "count_mailboxes": 0,
     }
 
     # a new domain with status "failed" is created and authenticated user is the owner

src/backend/mailbox_manager/tests/api/mail_domain/test_api_mail_domains_retrieve.py

@@ -71,6 +71,7 @@ def test_api_mail_domains__retrieve_authenticated_related():
 
     domain = factories.MailDomainEnabledFactory()
     factories.MailDomainAccessFactory(domain=domain, user=user)
+    factories.MailboxFactory.create_batch(10, domain=domain)
 
     response = client.get(
         f"/api/v1.0/mail-domains/{domain.slug}/",
@@ -85,4 +86,5 @@ def test_api_mail_domains__retrieve_authenticated_related():
         "created_at": domain.created_at.isoformat().replace("+00:00", "Z"),
         "updated_at": domain.updated_at.isoformat().replace("+00:00", "Z"),
         "abilities": domain.get_abilities(user),
+        "count_mailboxes": 10,
     }