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

[Hannes Laimer]

On Tue Apr 16, 2024 at 10:05 AM CEST, Christian Ebner wrote:
> 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!(),
>      };
> ```
>

makes sense, will do in v4

> > +
> > +        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)