test: Remove snapshot option from install_new_cloud_init (#4682)

Integration tests allow for installing a new version of cloud-init with
the option of snapshotting the image after install. After taking
a snapshot, it will then set the snapshot as the default for *all*
future launches in this test run. This is also used by the conftest to
setup the initial image, but it should not be used anywhere else.

Rather than having it as an option to the install_new_cloud_init method,
remove the option and make the confest set the global snapshot instead.
This removes a footgun when writing other tests that need to install a
different version of cloud-init.

tests/integration_tests/bugs/test_lp1835584.py

@@ -94,7 +94,5 @@ def test_azure_kernel_upgrade_case_insensitive_uuid(
         # We can't use setup_image fixture here because we want to avoid
         # taking a snapshot or cleaning the booted machine after cloud-init
         # upgrade.
-        instance.install_new_cloud_init(
-            source, take_snapshot=False, clean=False
-        )
+        instance.install_new_cloud_init(source, clean=False)
         _check_iid_insensitive_across_kernel_upgrade(instance)

tests/integration_tests/conftest.py

@@ -120,6 +120,9 @@ def setup_image(session_cloud: IntegrationCloud, request):
     log.info("Setting up environment for %s", session_cloud.datasource)
     client = session_cloud.launch()
     client.install_new_cloud_init(source)
+    # All done customizing the image, so snapshot it and make it global
+    snapshot_id = client.snapshot()
+    client.cloud.snapshot_id = snapshot_id
     # Even if we're keeping instances, we don't want to keep this
     # one around as it was just for image creation
     client.destroy()

tests/integration_tests/instances.py

@@ -127,7 +127,6 @@ def snapshot(self):
     def install_new_cloud_init(
         self,
         source: CloudInitSource,
-        take_snapshot=True,
         clean=True,
     ):
         if source == CloudInitSource.DEB_PACKAGE:
@@ -148,9 +147,6 @@ def install_new_cloud_init(
         log.info("Installed cloud-init version: %s", version)
         if clean:
             self.instance.clean()
-        if take_snapshot:
-            snapshot_id = self.snapshot()
-            self.cloud.snapshot_id = snapshot_id
 
     # assert with retry because we can compete with apt already running in the
     # background and get: E: Could not get lock /var/lib/apt/lists/lock - open

tests/integration_tests/test_kernel_commandline_match.py

@@ -131,9 +131,7 @@ def test_lxd_datasource_kernel_override_nocloud_net(
         client.instance.execute_via_ssh = False  # pyright: ignore
         assert wait_for_cloud_init(client, num_retries=60).ok
         if source.installs_new_version():
-            client.install_new_cloud_init(
-                source, take_snapshot=False, clean=False
-            )
+            client.install_new_cloud_init(source, clean=False)
         override_kernel_cmdline(ds_str, client)
 
         logs = client.execute("cat /var/log/cloud-init.log")

tests/integration_tests/test_upgrade.py

@@ -88,7 +88,7 @@ def test_clean_boot_of_upgraded_package(session_cloud: IntegrationCloud):
             )
 
         # Upgrade
-        instance.install_new_cloud_init(source, take_snapshot=False)
+        instance.install_new_cloud_init(source)
 
         # 'cloud-init init' helps us understand if our pickling upgrade paths
         # have broken across re-constitution of a cached datasource. Some
@@ -185,9 +185,7 @@ def test_subsequent_boot_of_upgraded_package(session_cloud: IntegrationCloud):
     launch_kwargs = {"image_id": session_cloud.initial_image_id}
 
     with session_cloud.launch(launch_kwargs=launch_kwargs) as instance:
-        instance.install_new_cloud_init(
-            source, take_snapshot=False, clean=False
-        )
+        instance.install_new_cloud_init(source, clean=False)
         instance.restart()
         log = instance.read_from_file("/var/log/cloud-init.log")
         verify_clean_log(log)