[pve-devel] [PATCH pve-cluster 1/1] notify: add common_template_data

[Lukas Wagner]

On  2025-03-27 16:31, Thomas Lamprecht wrote:
> Am 27.03.25 um 15:23 schrieb Lukas Wagner:
>> This commit add the `common_template_data` sub to PVE::Notify,
>> providing a convenient way to get a hash with properties that
>> should be accessible from all templates, namely hostname, fqdn
>> and cluster-name.
>>
>> Signed-off-by: Lukas Wagner <l.wagner at proxmox.com>
>> ---
>>  src/PVE/Notify.pm | 20 ++++++++++++++++++++
>>  1 file changed, 20 insertions(+)
>>
>> diff --git a/src/PVE/Notify.pm b/src/PVE/Notify.pm
>> index c514111..9f7a74c 100644
>> --- a/src/PVE/Notify.pm
>> +++ b/src/PVE/Notify.pm
>> @@ -4,6 +4,7 @@ use strict;
>>  use warnings;
>>  
>>  use PVE::Cluster qw(cfs_register_file cfs_read_file cfs_lock_file cfs_write_file);
>> +use PVE::INotify;
>>  use Proxmox::RS::Notify;
>>  
>>  cfs_register_file(
>> @@ -130,4 +131,23 @@ sub check_may_use_target {
>>      }
>>  }
>>  
>> +sub common_template_data {
>> +    my $hostname = PVE::INotify::nodename();
>> +    my $fqdn = `hostname -f` || $hostname;
>> +    chomp $fqdn;
> 
> A bit odd seeing the highly efficient hostname cached from inotify used
> with getting the FQDN in a rather expensive (fork+exec) way.
> Not so keen on the use of backticks, albeit it would not be a huge
> problem.
> 
> I'd favor using PVE::Tools::get_fqdn which should work as well as calling
> `hostname -f` but also be quite a bit cheaper due to avoiding fork+exec.
> It'd be probably even fine to cache in a module-local variable, as this
> is not something that changes often, but also probably not a must for now.
> 

Yeah, fair. The `hostname -f` was pre-existing in the place where we send APT update notifications,
I just moved it from there. I didn't know that there was a helper for it, good to know!
I'll check it out and send a v2.

We of course can cache the FQDN, but realistically speaking, this is only called once per
notification being sent, thus any real-world performance impact is absolutely tiny.

Thanks for the feedback!

-- 
- Lukas