implement django-admin domains --stale-check

nsupdate/management/commands/domains.py

@@ -9,7 +9,7 @@ from django.core.mail import send_mail
 from django.db import transaction
 from django.utils.translation import ugettext_lazy as _
 
-from nsupdate.main.models import Domain
+from nsupdate.main.models import Domain, Host
 from nsupdate.main.dnstools import FQDN, query_ns, NameServerNotAvailable
 from nsupdate.utils.mail import translate_for_user, send_mail_to_user
 
@@ -40,6 +40,11 @@ hosts that were added to this domain (if any).
 """)
 
 
+LOG_MSG_IS_AVAILABLE = _('Domain %%(domain)s is available.')
+LOG_MSG_HAS_HOSTS = _('Domain %%(domain)s is not available, but has %(hosts)d hosts.')
+LOG_MSG_DELETE = _('Domain %%(domain)s is not available and has no hosts -> deleted domain.')
+
+
 def check_dns(domain):
     """
     checks if the nameserver is reachable and answers queries for the domain.
@@ -62,6 +67,28 @@ def check_dns(domain):
     return queries_ok
 
 
+def check_staleness(d):
+    """
+    checks the staleness of Domain d (is not available and has no hosts) and if it is stale, delete it.
+
+    Return log msg (can be None).
+
+    :param d: Domain instance
+    :return: log_msg
+    """
+    if d.available:
+        log_msg = LOG_MSG_IS_AVAILABLE
+    else:
+        host_count = Host.objects.filter(domain=d).count()
+        if host_count > 0:
+            log_msg = LOG_MSG_HAS_HOSTS % dict(hosts=host_count)
+        else:
+            # is not available and has no hosts
+            d.delete()
+            log_msg = LOG_MSG_DELETE
+    return log_msg
+
+
 class Command(BaseCommand):
     help = 'deal with domains'
 
@@ -76,14 +103,20 @@ class Command(BaseCommand):
                             dest='notify_user',
                             default=False,
                             help='notify the user by email when domain gets flagged as unavailable')
+        parser.add_argument('--stale-check',
+                            action='store_true',
+                            dest='stale_check',
+                            default=False,
+                            help='check whether domain is available or has hosts, delete if not')
 
     def handle(self, *args, **options):
         check = options['check']
+        stale_check = options['stale_check']
         notify_user = options['notify_user']
         with transaction.atomic():
             for d in Domain.objects.all():
-                if check and d.available:
                 domain = d.name
+                if check and d.available:
                     comment = d.comment
                     creator = d.created_by
                     available = check_dns(domain)
@@ -102,3 +135,8 @@ class Command(BaseCommand):
                         msg = "setting unavailable flag for domain %s (created by %s)\n" % (domain, creator,)
                         self.stdout.write(msg)
                     d.save()
+                if stale_check:
+                    log_msg = check_staleness(d)
+                    if log_msg:
+                        log_msg = log_msg % dict(domain=domain)
+                        self.stdout.write(log_msg)