[cloud] Delete underlying snapshots when deleting Alibaba Cloud images

The underlying snapshots are not automatically deleted along with the
image, and there is no flag that can be set to cause them to be
automatically deleted.

Tag the underlying snapshots for deletion before deleting the image,
delete the image, and then delete any such tagged snapshots (including
any that may remain from a previous failed deletion attempt).

Signed-off-by: Michael Brown <mcb30@ipxe.org>

contrib/cloud/ali-import

diff --git a/contrib/cloud/ali-import b/contrib/cloud/ali-import
index 88c08cb..0794a5c 100755
--- a/contrib/cloud/ali-import
+++ b/contrib/cloud/ali-import
@@ -82,6 +82,7 @@
 OSS_BUCKET_NAME_LEN = 63
 
 IPXE_STORAGE_PREFIX = 'ipxe-upload-temp-'
+IPXE_SNAPSHOT_DELETE_TAG = 'ipxe-snapshot-delete'
 
 POLL_INTERVAL_SEC = 5
 POLL_MAX_RETRIES = 100
@@ -389,6 +390,21 @@
     for image in rsp.body.images.image or ():
         logger.info("delete image %s %s (%s)" %
                     (clients.region, image.image_name, image.image_id))
+        # Tag associated snapshots for deletion
+        for disk in image.disk_device_mappings.disk_device_mapping or ():
+            snapshot_id = disk.snapshot_id
+            tag = ecs.models.TagResourcesRequestTag(
+                key=IPXE_SNAPSHOT_DELETE_TAG,
+                value=IPXE_SNAPSHOT_DELETE_TAG,
+            )
+            req = ecs.models.TagResourcesRequest(
+                region_id=clients.region,
+                resource_type='snapshot',
+                resource_id=[snapshot_id],
+                tag=[tag],
+            )
+            rsp = clients.ecs.tag_resources_with_options(req, RUNTIME_OPTS)
+        # Unpublish image
         if image.is_public:
             req = ecs.models.ModifyImageSharePermissionRequest(
                 region_id=clients.region,
@@ -398,11 +414,31 @@
             rsp = clients.ecs.modify_image_share_permission_with_options(
                 req, RUNTIME_OPTS
             )
+        # Delete image
         req = ecs.models.DeleteImageRequest(
             region_id=clients.region,
             image_id=image.image_id
         )
         rsp = clients.ecs.delete_image_with_options(req, RUNTIME_OPTS)
+    # Delete any snapshots tagged for deletion
+    tag = ecs.models.ListTagResourcesRequestTag(
+        key=IPXE_SNAPSHOT_DELETE_TAG,
+        value=IPXE_SNAPSHOT_DELETE_TAG,
+    )
+    req = ecs.models.ListTagResourcesRequest(
+        region_id=clients.region,
+        resource_type='snapshot',
+        tag=[tag],
+    )
+    rsp = clients.ecs.list_tag_resources_with_options(req, RUNTIME_OPTS)
+    for snapshot in rsp.body.tag_resources.tag_resource or ():
+        logger.info("delete snapshot %s %s" %
+                    (clients.region, snapshot.resource_id))
+        req = ecs.models.DeleteSnapshotRequest(
+            snapshot_id=snapshot.resource_id,
+            force=True,
+        )
+        rsp = clients.ecs.delete_snapshot_with_options(req, RUNTIME_OPTS)
 
 def wait_for_task(clients, task_id):
     """Wait for task to complete"""