Ability to remove instances.

awx/main/management/commands/remove_instance.py

@@ -0,0 +1,54 @@
+# Copyright (c) 2014 Ansible, Inc.
+# All Rights Reserved
+
+from optparse import make_option
+
+from django.conf import settings
+from django.core.management.base import BaseCommand, CommandError
+
+from awx.main.models import Instance
+
+
+class Command(BaseCommand):
+    """Remove an existing instance from the HA instance table.
+
+    This command is idempotent. It will remove the machine if it is
+    present and do nothing if the machine is absent.
+
+    This command will cowardly refuse to remove the primary machine.
+    """
+    option_list = BaseCommand.option_list + (
+        make_option('--hostname', dest='hostname', default=''),
+        make_option('--uuid', dest='uuid', default=''),
+    )
+
+    def handle(self, **options):
+        # Remove any empty options from the options dictionary.
+        fields = {}
+        for field in ('uuid', 'hostname'):
+            if options[field]:
+                fields[field] = options[field]
+
+        # At least one of hostname or uuid must be set.
+        if not fields:
+            raise CommandError('You must provide either --uuid or --hostname.')
+
+        # Is there an existing record for this machine?
+        # If so, retrieve that record and look for issues.
+        try:
+            # Get the instance.
+            instance = Instance.objects.get(**fields)
+
+            # Sanity check: Do not remove the primary instance.
+            if instance.primary:
+                raise CommandError('I cowardly refuse to remove the primary '
+                                   'instance.')
+
+            # Remove the instance.
+            instance.delete()
+            dirty = True
+        except Instance.DoesNotExist:
+            dirty = False
+
+        # Done!
+        print('Instance removed (changed: %r).' % dirty)