[pbs-devel] [PATCH proxmox-backup v3 12/24] add auto-mounting for removable datastores

[Christian Ebner]

comments inline

On 4/9/24 13:00, Hannes Laimer wrote:
> Signed-off-by: Hannes Laimer <h.laimer at proxmox.com>
> ---
>   debian/proxmox-backup-server.install        |  1 +
>   debian/proxmox-backup-server.udev           |  3 ++
>   etc/Makefile                                |  3 +-
>   etc/removable-device-attach at .service.in     |  8 +++
>   src/bin/proxmox_backup_manager/datastore.rs | 55 +++++++++++++++++++++
>   5 files changed, 69 insertions(+), 1 deletion(-)
>   create mode 100644 etc/removable-device-attach at .service.in
> 
> diff --git a/debian/proxmox-backup-server.install b/debian/proxmox-backup-server.install
> index ee114ea3..cda01069 100644
> --- a/debian/proxmox-backup-server.install
> +++ b/debian/proxmox-backup-server.install
> @@ -4,6 +4,7 @@ etc/proxmox-backup-daily-update.service /lib/systemd/system/
>   etc/proxmox-backup-daily-update.timer /lib/systemd/system/
>   etc/proxmox-backup-proxy.service /lib/systemd/system/
>   etc/proxmox-backup.service /lib/systemd/system/
> +etc/removable-device-attach at .service /lib/systemd/system/
>   usr/bin/pmt
>   usr/bin/pmtx
>   usr/bin/proxmox-tape
> diff --git a/debian/proxmox-backup-server.udev b/debian/proxmox-backup-server.udev
> index afdfb2bc..e21b8bc7 100644
> --- a/debian/proxmox-backup-server.udev
> +++ b/debian/proxmox-backup-server.udev
> @@ -16,3 +16,6 @@ SUBSYSTEM=="scsi_generic", SUBSYSTEMS=="scsi", ATTRS{type}=="1", ENV{ID_SCSI_SER
>     SYMLINK+="tape/by-id/scsi-$env{ID_SCSI_SERIAL}-sg"
>   
>   LABEL="persistent_storage_tape_end"
> +
> +# triggers the mounting of a removable device
> +ACTION=="add", SUBSYSTEM=="block", ENV{ID_FS_UUID}!="", TAG+="systemd", ENV{SYSTEMD_WANTS}="removable-device-attach@$env{ID_FS_UUID}"
> \ No newline at end of file
> diff --git a/etc/Makefile b/etc/Makefile
> index 42f639f6..730de4f8 100644
> --- a/etc/Makefile
> +++ b/etc/Makefile
> @@ -7,7 +7,8 @@ DYNAMIC_UNITS := \
>   	proxmox-backup-banner.service \
>   	proxmox-backup-daily-update.service \
>   	proxmox-backup.service \
> -	proxmox-backup-proxy.service
> +	proxmox-backup-proxy.service \
> +	removable-device-attach at .service
>   
>   all: $(UNITS) $(DYNAMIC_UNITS) pbs-enterprise.list
>   
> diff --git a/etc/removable-device-attach at .service.in b/etc/removable-device-attach at .service.in
> new file mode 100644
> index 00000000..fe256548
> --- /dev/null
> +++ b/etc/removable-device-attach at .service.in
> @@ -0,0 +1,8 @@
> +[Unit]
> +Description=Try to mount the removable device of a datastore with uuid '%i'.
> +After=proxmox-backup-proxy.service
> +Requires=proxmox-backup-proxy.service
> +
> +[Service]
> +Type=simple
> +ExecStart=/usr/sbin/proxmox-backup-manager datastore uuid-mount --uuid %i
> \ No newline at end of file
> diff --git a/src/bin/proxmox_backup_manager/datastore.rs b/src/bin/proxmox_backup_manager/datastore.rs
> index f8462459..319d5eb0 100644
> --- a/src/bin/proxmox_backup_manager/datastore.rs
> +++ b/src/bin/proxmox_backup_manager/datastore.rs
> @@ -195,6 +195,60 @@ async fn delete_datastore(mut param: Value, rpcenv: &mut dyn RpcEnvironment) ->
>       Ok(())
>   }
>   
> +#[api(
> +    protected: true,
> +    input: {
> +        properties: {
> +            uuid: {
> +                type: String,
> +                description: "The UUID of the device that should be mounted",
> +            },
> +            "output-format": {
> +                schema: OUTPUT_FORMAT,
> +                optional: true,
> +            },
> +        },
> +    },
> +)]
> +/// Try mounting a removable datastore given the UUID.
> +async fn uuid_mount(mut param: Value, rpcenv: &mut dyn RpcEnvironment) -> Result<Value, Error> {
> +    let output_format = extract_output_format(&mut param);
> +    let uuid = param["uuid"]
> +        .as_str()
> +        .ok_or_else(|| format_err!("uuid has to be specified"))?;
> +
> +    let info = &api2::config::datastore::API_METHOD_LIST_DATASTORES;
> +    let data: Value = match info.handler {
> +        ApiHandler::Sync(handler) => (handler)(serde_json::json!({}), info, rpcenv)?,
> +        _ => unreachable!(),
> +    };
> +
> +    let store_name = data.as_array().and_then(|list| {
> +        list.iter()
> +            .filter_map(Value::as_object)
> +            .find(|store| store.get("backing-device").map_or(false, |d| d.eq(&uuid)))
> +            .and_then(|s| s.get("name").and_then(Value::as_str))
> +    });
> +
> +    if let Some(store_name) = store_name {
> +        let client = connect_to_localhost()?;
> +        let result = client
> +            .post(
> +                &format!("api2/json/admin/datastore/{}/mount", store_name),
> +                None,
> +            )
> +            .await?;

Did not test this, but could this also be done by creating a new `param` 
instance containing the `store` and `node` and call it via the code below?
```
     let info = &api2::admin::datastore::API_METHOD_MOUNT;
     let result = match info.handler {
         ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
         _ => unreachable!(),
     };
```

> +
> +        view_task_result(&client, result, &output_format).await?;
> +        Ok(Value::Null)
> +    } else {
> +        Err(format_err!(
> +            "'{}' is not associated with any datastore",
> +            &uuid
> +        ))

use bail and inline uuid, removing unneeded reference

> +    }
> +}
> +
>   pub fn datastore_commands() -> CommandLineInterface {
>       let cmd_def = CliCommandMap::new()
>           .insert("list", CliCommand::new(&API_METHOD_LIST_DATASTORES))
> @@ -240,6 +294,7 @@ pub fn datastore_commands() -> CommandLineInterface {
>                       pbs_config::datastore::complete_calendar_event,
>                   ),
>           )
> +        .insert("uuid-mount", CliCommand::new(&API_METHOD_UUID_MOUNT))
>           .insert(
>               "remove",
>               CliCommand::new(&API_METHOD_DELETE_DATASTORE)