✨(domains) notify support when domain status changes

During the scheduled task to check domains,
send an email notification to domain support if a
status has changed.

src/backend/mailbox_manager/models.py

@@ -2,12 +2,17 @@
 Declare and configure the models for the People additional application : mailbox_manager
 """
 
+import logging
+import smtplib
+
 from django.conf import settings
 from django.contrib.auth.base_user import AbstractBaseUser
-from django.core import exceptions, validators
+from django.contrib.sites.models import Site
+from django.core import exceptions, mail, validators
 from django.db import models
+from django.template.loader import render_to_string
 from django.utils.text import slugify
-from django.utils.translation import gettext
+from django.utils.translation import get_language, gettext, override
 from django.utils.translation import gettext_lazy as _
 
 from core.models import BaseInvitation, BaseModel, Organization, User
@@ -18,6 +23,28 @@ from mailbox_manager.enums import (
     MailDomainStatusChoices,
 )
 
+logger = logging.getLogger(__name__)
+
+
+STATUS_NOTIFICATION_MAILS = {
+    # new status domain: (mail subject, mail template html, mail template text)
+    MailDomainStatusChoices.ENABLED: (
+        _("[La Suite] Your domain is ready"),
+        "mail/html/maildomain_enabled.html",
+        "mail/text/maildomain_enabled.txt",
+    ),
+    MailDomainStatusChoices.ACTION_REQUIRED: (
+        _("[La Suite] Your domain requires action"),
+        "mail/html/maildomain_action_required.html",
+        "mail/text/maildomain_action_required.txt",
+    ),
+    MailDomainStatusChoices.FAILED: (
+        _("[La Suite] Your domain has failed"),
+        "mail/html/maildomain_failed.html",
+        "mail/text/maildomain_failed.txt",
+    ),
+}
+
 
 class MailDomain(BaseModel):
     """Domain names from which we will create email addresses (mailboxes)."""
@@ -104,6 +131,45 @@ class MailDomain(BaseModel):
             bool(self.organization) and self.status == MailDomainStatusChoices.ENABLED
         )
 
+    def notify_status_change(self, recipients=None, language=None):
+        """
+        Notify the support team that the domain status has changed.
+        """
+        subject, template_html, template_text = STATUS_NOTIFICATION_MAILS.get(
+            self.status, (None, None, None)
+        )
+        if not subject:
+            return
+        context = {
+            "title": subject,
+            "domain_name": self.name,
+            "manage_domain_url": (
+                f"{Site.objects.get_current().domain}/mail-domains/{self.slug}/"
+            ),
+        }
+        try:
+            with override(language or get_language()):
+                mail.send_mail(
+                    subject,
+                    render_to_string(template_text, context),
+                    settings.EMAIL_FROM,
+                    recipients or [self.support_email],
+                    html_message=render_to_string(template_html, context),
+                    fail_silently=False,
+                )
+        except smtplib.SMTPException as exception:
+            logger.error(
+                "Notification email to %s was not sent: %s",
+                self.support_email,
+                exception,
+            )
+        else:
+            logger.info(
+                "Information about domain %s sent to %s.",
+                self.name,
+                self.support_email,
+            )
+
 
 class MailDomainAccess(BaseModel):
     """Allow to manage users' accesses to mail domains."""