Re: [pbs-devel] [PATCH proxmox-backup 02/26] config: make RemovableDeviceConfig savable to config file

[Wolfgang Bumiller <w.bumiller@proxmox.com>]

Design question:

Do we need this to be a separate config file though? Can this not simply
be part of the datastore directly? We already "link" them by having to
define the datastore as `removable`, so can we not just put all the
values in there?

On Tue, Jul 05, 2022 at 01:08:10PM +0000, Hannes Laimer wrote:
> Signed-off-by: Hannes Laimer <h.laimer@proxmox.com>
> ---
>  pbs-config/src/lib.rs              |  1 +
>  pbs-config/src/removable_device.rs | 63 ++++++++++++++++++++++++++++++
>  2 files changed, 64 insertions(+)
>  create mode 100644 pbs-config/src/removable_device.rs
> 
> diff --git a/pbs-config/src/lib.rs b/pbs-config/src/lib.rs
> index a83db4e1..5ea67652 100644
> --- a/pbs-config/src/lib.rs
> +++ b/pbs-config/src/lib.rs
> @@ -10,6 +10,7 @@ pub mod metrics;
>  pub mod network;
>  pub mod prune;
>  pub mod remote;
> +pub mod removable_device;
>  pub mod sync;
>  pub mod tape_encryption_keys;
>  pub mod tape_job;
> diff --git a/pbs-config/src/removable_device.rs b/pbs-config/src/removable_device.rs
> new file mode 100644
> index 00000000..4587d72b
> --- /dev/null
> +++ b/pbs-config/src/removable_device.rs
> @@ -0,0 +1,63 @@
> +use std::collections::HashMap;
> +
> +use anyhow::Error;
> +use lazy_static::lazy_static;
> +
> +use pbs_api_types::{RemovableDeviceConfig, DEVICE_NAME_SCHEMA};
> +use proxmox_schema::*;
> +use proxmox_section_config::{SectionConfig, SectionConfigData, SectionConfigPlugin};
> +
> +use crate::{open_backup_lockfile, replace_backup_config, BackupLockGuard};
> +
> +lazy_static! {
> +    pub static ref CONFIG: SectionConfig = init();
> +}
> +
> +fn init() -> SectionConfig {
> +    const OBJ_SCHEMA: &ObjectSchema = RemovableDeviceConfig::API_SCHEMA.unwrap_object_schema();
> +
> +    let plugin = SectionConfigPlugin::new(
> +        "removable-device".to_string(),
> +        Some(String::from("name")),
> +        OBJ_SCHEMA,
> +    );
> +    let mut config = SectionConfig::new(&DEVICE_NAME_SCHEMA);
> +    config.register_plugin(plugin);
> +
> +    config
> +}
> +
> +pub const REMOVABLE_DEVIVE_CFG_FILENAME: &str = "/etc/proxmox-backup/removable-device.cfg";
> +pub const REMOVABLE_DEVIVE_CFG_LOCKFILE: &str = "/etc/proxmox-backup/.removable-device.lck";
> +
> +/// Get exclusive lock
> +pub fn lock_config() -> Result<BackupLockGuard, Error> {
> +    open_backup_lockfile(REMOVABLE_DEVIVE_CFG_LOCKFILE, None, true)
> +}
> +
> +pub fn config() -> Result<(SectionConfigData, [u8; 32]), Error> {
> +    let content = proxmox_sys::fs::file_read_optional_string(REMOVABLE_DEVIVE_CFG_FILENAME)?;
> +    let content = content.unwrap_or_default();
> +
> +    let digest = openssl::sha::sha256(content.as_bytes());
> +    let data = CONFIG.parse(REMOVABLE_DEVIVE_CFG_FILENAME, &content)?;
> +
> +    Ok((data, digest))
> +}
> +
> +pub fn save_config(config: &SectionConfigData) -> Result<(), Error> {
> +    let raw = CONFIG.write(REMOVABLE_DEVIVE_CFG_FILENAME, config)?;
> +    replace_backup_config(REMOVABLE_DEVIVE_CFG_FILENAME, raw.as_bytes())
> +}
> +
> +// shell completion helper
> +pub fn complete_removable_device_name(_arg: &str, _param: &HashMap<String, String>) -> Vec<String> {
> +    match config() {
> +        Ok((data, _digest)) => data
> +            .sections
> +            .iter()
> +            .map(|(name, _)| name.to_string())
> +            .collect(),
> +        Err(_) => return vec![],
> +    }
> +}
> -- 
> 2.30.2