Re: [PATCH proxmox-backup 3/7] api: add /nodes/localhost/instance-id

["Lukas Wagner" <l.wagner@proxmox.com>]

Thanks for the feedback, Chris!


On Tue Apr 14, 2026 at 4:23 PM CEST, Christian Ebner wrote:
> On 4/13/26 2:11 PM, Lukas Wagner wrote:
>>   }
>>   
>> +///  Static key used for deriving a unique instance id from `/etc/machine-id` using
>> +///  [`proxmox_systemd::sd_id128::get_app_specific_id`].
>> +///
>> +///  This key was generated `systemd-id128 new`.
>
> nit: ... generated by `systemd-id128 new`

Fixed for v2, thanks :)

>
>> +///
>> +const INSTANCE_ID_KEY: [u8; 16] = 0xe5415d9999c146399b8bdae1260e19d2_u128.to_le_bytes();
>> +
>> +#[api(
>> +    protected: false,
>
> nit: no need to set this explicitly.

ack!

>
>> +    input: {
>> +        properties: {
>> +            node: {
>> +                schema: NODE_SCHEMA,
>> +                optional: true,
>> +            },
>> +        }
>> +    },
>> +    returns: {
>> +        type: InstanceId,
>> +    },
>> +    access: {
>> +        permission: &Permission::Anybody,
>> +    }
>> +)]
>> +/// Returns a unique ID for this PBS node. The ID is derived from `/etc/machine-id`.
>> +pub fn get_instance_id() -> Result<InstanceId, Error> {
>> +    let machine_id_derived_app_id =
>> +        proxmox_systemd::sd_id128::get_app_specific_id(INSTANCE_ID_KEY)?;
>> +    let machine_id_derived_app_id = hex::encode(machine_id_derived_app_id);
>> +
>> +    Ok(InstanceId {
>> +        instance_id: machine_id_derived_app_id,
>
> nit: Could make sense to derive `From` for this on the `InstanceId` itself?
>
> But do not want to pollute the api-types with dependencies on 
> proxmox-systemd, so this would only cover the plain id to string 
> conversion... so not sure if worth it.
>


I created a struct for this response instead of just returning a string
so that it's extensible in the future, in case we want to return more
information. With that in mind, the `From` impl does not make that much
sense to me, if I'm honest.

I think I'd prefer this as is, if that is alright with you? I don't
think the `From` helps much when it comes to maintainability nor
readability here.

>> +    })
>> +}
>> +
>>   pub const SUBDIRS: SubdirMap = &[
>>       ("apt", &apt::ROUTER),
>>       ("certificates", &certificates::ROUTER),
>>       ("config", &config::ROUTER),
>>       ("disks", &disks::ROUTER),
>>       ("dns", &dns::ROUTER),
>> +    (
>> +        "instance-id",
>> +        &Router::new().get(&API_METHOD_GET_INSTANCE_ID),
>> +    ),
>>       ("journal", &journal::ROUTER),
>>       ("network", &network::ROUTER),
>>       ("report", &report::ROUTER),