test: Add instance id integration test

tests/integration_tests/test_instance_id.py

@@ -0,0 +1,96 @@
+from typing import cast
+import pytest
+from pycloudlib.lxd.instance import LXDInstance
+
+from cloudinit import subp
+from tests.integration_tests.instances import IntegrationInstance
+from tests.integration_tests.integration_settings import PLATFORM
+
+_INSTANCE_ID = 0
+
+
+def setup_meta_data(instance: LXDInstance):
+    """Increment the instance id and apply it to the instance."""
+    global _INSTANCE_ID
+    _INSTANCE_ID += 1
+    command = [
+        "lxc",
+        "config",
+        "set",
+        instance.name,
+        f"user.meta-data=instance-id: test_{_INSTANCE_ID}",
+    ]
+    subp.subp(command)
+
+
+# class TestInstanceID:
+@pytest.mark.skipif(
+    PLATFORM not in ["lxd_container", "lxd_vm"],
+    reason="Uses lxd-specific behavior.",
+)
+@pytest.mark.lxd_setup.with_args(setup_meta_data)
+@pytest.mark.lxd_use_exec
+def test_instance_id_changes(client: IntegrationInstance):
+    """Verify instance id change behavior
+
+    If the id from the datasource changes, cloud-init should update the
+    instance id link.
+    """
+    client.execute("cloud-init status --wait")
+    # check that instance id is the one we set
+    assert (
+        "test_1"
+        == client.execute("cloud-init query instance-id").stdout.rstrip()
+    )
+    assert (
+        "/var/lib/cloud/instances/test_1"
+        == client.execute(
+            "readlink -f /var/lib/cloud/instance"
+        ).stdout.rstrip()
+    )
+
+    instance = cast(LXDInstance, client.instance)
+    setup_meta_data(instance)
+    client.restart()
+    client.execute("cloud-init status --wait")
+    # check that instance id is the one we reset
+    assert (
+        "test_2"
+        == client.execute("cloud-init query instance-id").stdout.rstrip()
+    )
+    assert (
+        "/var/lib/cloud/instances/test_2"
+        == client.execute(
+            "readlink -f /var/lib/cloud/instance"
+        ).stdout.rstrip()
+    )
+
+
+@pytest.mark.lxd_use_exec
+def test_instance_id_no_changes(client: IntegrationInstance):
+    """Verify instance id no change behavior
+
+    If the id from the datasource does not change, cloud-init should not
+    update the instance id link.
+    """
+    instance_id = client.execute(
+        "cloud-init query instance-id"
+    ).stdout.rstrip()
+    assert (
+        f"/var/lib/cloud/instances/{instance_id}"
+        == client.execute(
+            "readlink -f /var/lib/cloud/instance"
+        ).stdout.rstrip()
+    )
+    client.restart()
+    client.execute("cloud-init status --wait")
+    assert (
+        instance_id
+        == client.execute("cloud-init query instance-id").stdout.rstrip()
+    )
+    assert (
+        f"/var/lib/cloud/instances/{instance_id}"
+        == client.execute(
+            "readlink -f /var/lib/cloud/instance"
+        ).stdout.rstrip()
+    )