Capture hop nodes and the peer links between nodes

awx/main/migrations/0156_capture_mesh_topology.py

@@ -0,0 +1,44 @@
+# Generated by Django 2.2.20 on 2021-12-17 19:26
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('main', '0155_improved_health_check'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='instance',
+            name='node_type',
+            field=models.CharField(
+                choices=[
+                    ('control', 'Control plane node'),
+                    ('execution', 'Execution plane node'),
+                    ('hybrid', 'Controller and execution'),
+                    ('hop', 'Message-passing node, no execution capability'),
+                ],
+                default='hybrid',
+                max_length=16,
+            ),
+        ),
+        migrations.CreateModel(
+            name='InstanceLink',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('source', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='+', to='main.Instance')),
+                ('target', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='reverse_peers', to='main.Instance')),
+            ],
+            options={
+                'unique_together': {('source', 'target')},
+            },
+        ),
+        migrations.AddField(
+            model_name='instance',
+            name='peers',
+            field=models.ManyToManyField(through='main.InstanceLink', to='main.Instance'),
+        ),
+    ]

awx/main/models/__init__.py

@@ -47,6 +47,7 @@ from awx.main.models.execution_environments import ExecutionEnvironment  # noqa
 from awx.main.models.activity_stream import ActivityStream  # noqa
 from awx.main.models.ha import (  # noqa
     Instance,
+    InstanceLink,
     InstanceGroup,
     TowerScheduleState,
 )

awx/main/models/ha.py

@@ -54,6 +54,14 @@ class HasPolicyEditsMixin(HasEditsMixin):
         return self._values_have_edits(new_values)
 
 
+class InstanceLink(BaseModel):
+    source = models.ForeignKey('Instance', on_delete=models.CASCADE, related_name='+')
+    target = models.ForeignKey('Instance', on_delete=models.CASCADE, related_name='reverse_peers')
+
+    class Meta:
+        unique_together = ('source', 'target')
+
+
 class Instance(HasPolicyEditsMixin, BaseModel):
     """A model representing an AWX instance running against this database."""
 
@@ -116,9 +124,16 @@ class Instance(HasPolicyEditsMixin, BaseModel):
         default=0,
         editable=False,
     )
-    NODE_TYPE_CHOICES = [("control", "Control plane node"), ("execution", "Execution plane node"), ("hybrid", "Controller and execution")]
+    NODE_TYPE_CHOICES = [
+        ("control", "Control plane node"),
+        ("execution", "Execution plane node"),
+        ("hybrid", "Controller and execution"),
+        ("hop", "Message-passing node, no execution capability"),
+    ]
     node_type = models.CharField(default='hybrid', choices=NODE_TYPE_CHOICES, max_length=16)
 
+    peers = models.ManyToManyField('self', symmetrical=False, through=InstanceLink, through_fields=('source', 'target'))
+
     class Meta:
         app_label = 'main'
         ordering = ("hostname",)