add secondary nameserver, prefer it for queries, add migration, fixes #175

conftest.py

@@ -20,6 +20,7 @@ TEST_SECRET2 = "somethingelse"
 RELATED_HOST_NAME = 'rh'
 TEST_HOST_RELATED = FQDN(RELATED_HOST_NAME + '.' + TEST_HOST.host, TEST_HOST.domain)
 NAMESERVER_IP = "85.10.192.104"
+NAMESERVER2_IP = NAMESERVER_IP  # use same server as tests query shortly after update, too quick for secondary
 NAMESERVER_UPDATE_ALGORITHM = "HMAC_SHA512"
 # no problem, you can ONLY update the TESTDOMAIN with this secret, nothing else:
 NAMESERVER_UPDATE_SECRET = "YWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYQ=="
@@ -75,6 +76,7 @@ def db_init(db):  # note: db is a predefined fixture and required here to have t
     dt = Domain.objects.create(
         name=TESTDOMAIN,  # special: test-domain update secret!
         nameserver_ip=NAMESERVER_IP,
+        nameserver2_ip=NAMESERVER2_IP,
         nameserver_update_algorithm=NAMESERVER_UPDATE_ALGORITHM,
         nameserver_update_secret=NAMESERVER_UPDATE_SECRET,
         public=NAMESERVER_PUBLIC,
@@ -84,6 +86,7 @@ def db_init(db):  # note: db is a predefined fixture and required here to have t
     d = Domain.objects.create(
         name=BASEDOMAIN,
         nameserver_ip=NAMESERVER_IP,
+        nameserver2_ip=NAMESERVER2_IP,
         nameserver_update_algorithm=NAMESERVER_UPDATE_ALGORITHM,
         nameserver_update_secret='invalid=',  # we don't send updates there (and the real key is really secret)
         public=NAMESERVER_PUBLIC,

nsupdate/main/dnstools.py

@@ -197,11 +197,14 @@ def query_ns(fqdn, rdtype):
     :raises: see dns.resolver.Resolver.query
     """
     assert isinstance(fqdn, FQDN)
-    nameserver, origin = get_ns_info(fqdn)[0:2]
+    nameserver, nameserver2, origin = get_ns_info(fqdn)[0:3]
     resolver = dns.resolver.Resolver(configure=False)
     # we do not configure it from resolv.conf, but patch in the values we
     # want into the documented attributes:
     resolver.nameservers = [nameserver, ]
+    if nameserver2:
+        # if we have a secondary ns, prefer it for queries
+        resolver.nameservers.insert(0, nameserver2)
     resolver.search = []
     resolver.lifetime = RESOLVER_TIMEOUT
     # as we query directly the (authoritative) master dns, we do not desire
@@ -269,7 +272,7 @@ def get_ns_info(fqdn):
             # retry timeout is over, set it available again
             set_ns_availability(domain, True)
     algorithm = getattr(dns.tsig, d.nameserver_update_algorithm)
-    return d.nameserver_ip, fqdn.domain, domain, fqdn.host, domain, d.nameserver_update_secret, algorithm
+    return d.nameserver_ip, d.nameserver2_ip, fqdn.domain, domain, fqdn.host, domain, d.nameserver_update_secret, algorithm
 
 
 def update_ns(fqdn, rdtype='A', ipaddr=None, action='upd', ttl=60):
@@ -286,7 +289,7 @@ def update_ns(fqdn, rdtype='A', ipaddr=None, action='upd', ttl=60):
     """
     assert isinstance(fqdn, FQDN)
     assert action in ['add', 'del', 'upd', ]
-    nameserver, origin, domain, name, keyname, key, algo = get_ns_info(fqdn)
+    nameserver, nameserver2, origin, domain, name, keyname, key, algo = get_ns_info(fqdn)
     upd = dns.update.Update(origin,
                             keyring=dns.tsigkeyring.from_text({keyname: key}),
                             keyalgorithm=algo)

nsupdate/main/forms.py

@@ -44,7 +44,7 @@ class EditRelatedHostForm(forms.ModelForm):
 class CreateDomainForm(forms.ModelForm):
     class Meta(object):
         model = Domain
-        fields = ['name', 'nameserver_ip', 'nameserver_update_algorithm',
+        fields = ['name', 'nameserver_ip', 'nameserver2_ip', 'nameserver_update_algorithm',
                   'public', 'available', 'comment']
         widgets = {
             'name': forms.widgets.TextInput(attrs=dict(autofocus=None)),
@@ -54,7 +54,7 @@ class CreateDomainForm(forms.ModelForm):
 class EditDomainForm(forms.ModelForm):
     class Meta(object):
         model = Domain
-        fields = ['comment', 'nameserver_ip', 'public', 'available',
+        fields = ['comment', 'nameserver_ip', 'nameserver2_ip', 'public', 'available',
                   'nameserver_update_algorithm', 'nameserver_update_secret']
 
 

nsupdate/main/migrations/0003_auto_20141115_2230.py

@@ -0,0 +1,26 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('main', '0002_auto_20141115_2227'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='domain',
+            name='nameserver2_ip',
+            field=models.GenericIPAddressField(help_text='IP of additional nameserver (used for queries)', null=True, verbose_name='nameserver IP (secondary)', blank=True),
+            preserve_default=True,
+        ),
+        migrations.AlterField(
+            model_name='domain',
+            name='nameserver_ip',
+            field=models.GenericIPAddressField(help_text='IP where the dynamic DNS updates for this zone will be sent to', verbose_name='nameserver IP (primary)'),
+            preserve_default=True,
+        ),
+    ]

nsupdate/main/models.py

@@ -83,9 +83,14 @@ class Domain(models.Model):
         unique=True,
         help_text=_("Name of the zone where dynamic hosts may get added"))
     nameserver_ip = models.GenericIPAddressField(
-        _("nameserver IP"),
+        _("nameserver IP (primary)"),
         max_length=40,  # ipv6 = 8 * 4 digits + 7 colons
         help_text=_("IP where the dynamic DNS updates for this zone will be sent to"))
+    nameserver2_ip = models.GenericIPAddressField(
+        _("nameserver IP (secondary)"),
+        max_length=40,  # ipv6 = 8 * 4 digits + 7 colons
+        blank=True, null=True,
+        help_text=_("IP of additional nameserver (used for queries)"))
     nameserver_update_secret = models.CharField(
         _("nameserver update secret"),
         max_length=88,  # 512 bits base64 -> 88 bytes