add routing templates model and initial migration

routing_templates/models.py

@@ -0,0 +1,45 @@
+import uuid
+
+from django.db import models, transaction
+from django.utils.translation import gettext_lazy as _
+
+from wireguard.models import WireGuardInstance
+
+
+class RoutingTemplate(models.Model):
+    ROUTE_TYPE_CHOICES = [
+        ("default", _('Default Route (0.0.0.0/0)')),
+        ("peer_same_instance", _('Routes from Peers on same Interface')),
+        ("peer_all_instances", _('Routes from All Peers')),
+        ("custom", _('Custom Routes')),
+    ]
+
+    wireguard_instance = models.ForeignKey(WireGuardInstance, on_delete=models.CASCADE)
+    default_template = models.BooleanField(default=False)
+
+    name = models.CharField(max_length=32)
+    route_type = models.CharField(max_length=20, choices=ROUTE_TYPE_CHOICES)
+
+    custom_routes = models.TextField(blank=True, null=True, help_text=_('One route per line in CIDR notation.'))
+    allow_peer_custom_routes = models.BooleanField(default=False)
+
+    uuid = models.UUIDField(default=uuid.uuid4, editable=False, unique=True)
+    created = models.DateTimeField(auto_now_add=True)
+    updated = models.DateTimeField(auto_now=True)
+
+    class Meta:
+        unique_together = (("wireguard_instance", "name"),)
+
+    def __str__(self):
+        return self.name
+
+    def save(self, *args, **kwargs):
+        with transaction.atomic():
+            super().save(*args, **kwargs)
+            if self.default_template:
+                (
+                    RoutingTemplate.objects
+                    .filter(wireguard_instance=self.wireguard_instance, default_template=True)
+                    .exclude(pk=self.pk)
+                    .update(default_template=False)
+                )