[PATCH container v6 12/18] api: record CT ID as used on destruction and remote migration

["Michael Köppl" <m.koeppl@proxmox.com>]

Record the ID of a CT as used when it is destroyed or removed after a
remote migration with --delete, so that the `/cluster/nextid` endpoint
can later optionally avoid suggesting previously used IDs.

For creation, restore and incoming remote migrations the ID is
recorded by create_and_lock_config(). Recording on destruction as well
covers guests that were created before IDs were tracked. The same holds
for a remote migration with --delete, which removes the source guest
without going through the destroy API; that call only warns on failure,
since the guest has already moved.

With 'unique' set in the next-id datacenter option, a failure to
record aborts create, clone and destroy before anything is changed.
Otherwise it only warns.

Originally-by: Daniel Krambrock <krambrock@hrz.uni-marburg.de>
Originally-by: Severen Redwood <severen.redwood@sitehost.co.nz>
Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
 src/PVE/API2/LXC.pm    | 5 +++++
 src/PVE/LXC/Migrate.pm | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/src/PVE/API2/LXC.pm b/src/PVE/API2/LXC.pm
index 5f94d5a1..fb4262c9 100644
--- a/src/PVE/API2/LXC.pm
+++ b/src/PVE/API2/LXC.pm
@@ -14,6 +14,7 @@ use PVE::DataCenterConfig;
 use PVE::Exception qw(raise raise_param_exc raise_perm_exc);
 use PVE::Firewall;
 use PVE::GuestHelpers;
+use PVE::GuestID;
 use PVE::INotify;
 use PVE::JSONSchema qw(get_standard_option);
 use PVE::RESTHandler;
@@ -882,6 +883,10 @@ __PACKAGE__->register_method({
 
         $early_checks->($conf);
 
+        # record before destroying anything, so a failure here leaves the CT intact
+        eval { PVE::GuestID::register_used_id($vmid) };
+        die "unable to destroy CT $vmid - $@" if $@;
+
         my $running_error_msg = "unable to destroy CT $vmid - container is running\n";
         die $running_error_msg if !$param->{force} && PVE::LXC::check_running($vmid); # check early
 
diff --git a/src/PVE/LXC/Migrate.pm b/src/PVE/LXC/Migrate.pm
index d243d901..a215dede 100644
--- a/src/PVE/LXC/Migrate.pm
+++ b/src/PVE/LXC/Migrate.pm
@@ -7,6 +7,7 @@ use File::Basename;
 use File::Copy; # fixme: remove
 
 use PVE::Cluster;
+use PVE::GuestID;
 use PVE::INotify;
 use PVE::JSONSchema;
 use PVE::Replication;
@@ -541,6 +542,9 @@ sub final_cleanup {
             PVE::Tunnel::write_tunnel($self->{tunnel}, 60, 'start');
         }
         if ($self->{opts}->{delete}) {
+            eval { PVE::GuestID::register_used_id($vmid) };
+            warn $@ if $@;
+
             PVE::LXC::destroy_lxc_container(
                 PVE::Storage::config(),
                 $vmid,
-- 
2.47.3