Re: [pve-devel] [PATCH storage] api: fix get content call for volumes

[Fiona Ebner <f.ebner@proxmox.com>]

Am 06.03.23 um 10:37 schrieb Christian Ebner:
> `pvesh get /nodes/{node}/storage/{storage}/content/{volume}` failed for
> several storage types, because the respective storage plugins returned
> only the volumes `size` on `volume_size_info` calls, while also the format
> is required.
> 
> This patch fixes the issue by returning also `format` and `used`, the
> latter also being a non-optional return value for the api call.
> 
> The issue was reported in the forum:
> https://forum.proxmox.com/threads/pvesh-get-nodes-node-storage-storage-content-volume-returns-error.123747/
> 
> Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
> ---
>  PVE/API2/Storage/Content.pm      | 2 +-
>  PVE/Storage/ISCSIDirectPlugin.pm | 2 +-
>  PVE/Storage/RBDPlugin.pm         | 2 +-
>  PVE/Storage/ZFSPoolPlugin.pm     | 2 +-
>  4 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/PVE/API2/Storage/Content.pm b/PVE/API2/Storage/Content.pm
> index fe0ad4a..36433ba 100644
> --- a/PVE/API2/Storage/Content.pm
> +++ b/PVE/API2/Storage/Content.pm
> @@ -324,7 +324,7 @@ __PACKAGE__->register_method ({
>  
>  	my $path = PVE::Storage::path($cfg, $volid);
>  	my ($size, $format, $used, $parent) =  PVE::Storage::volume_size_info($cfg, $volid);
> -	die "volume_size_info on '$volid' failed\n" if !($format && $size);
> +	die "volume_size_info on '$volid' failed\n" if !($format && $size && $used);

This change should be it's own patch and I think it's wrong. Can't $used
be zero and valid, e.g. for a newly created empty image? You'd either
need to use defined($used) or leave it as-is, i.e. not failing and
defaulting to 0 when $used is undef. Even with the defined() check, this
would break an external plugin that doesn't return $used. While I guess
that could be tolerated, we might do it together with the next APIAGE
reset and document that volume_size_info explicitly requires it.

>  
>  	my $entry = {
>  	    path => $path,
> diff --git a/PVE/Storage/ISCSIDirectPlugin.pm b/PVE/Storage/ISCSIDirectPlugin.pm
> index 9777969..eb329d4 100644
> --- a/PVE/Storage/ISCSIDirectPlugin.pm
> +++ b/PVE/Storage/ISCSIDirectPlugin.pm
> @@ -208,7 +208,7 @@ sub volume_size_info {
>      my $vollist = iscsi_ls($scfg,$storeid);
>      my $info = $vollist->{$storeid}->{$volname};
>  
> -    return $info->{size};
> +    return wantarray ? ($info->{size}, 'raw', 0, undef) : $info->{size};

Why return 0 for $used? Doesn't the API call then fail because of the
check you added above?

>  }
>  
>  sub volume_resize {
> diff --git a/PVE/Storage/RBDPlugin.pm b/PVE/Storage/RBDPlugin.pm
> index 9047504..e69c44c 100644
> --- a/PVE/Storage/RBDPlugin.pm
> +++ b/PVE/Storage/RBDPlugin.pm
> @@ -730,7 +730,7 @@ sub volume_size_info {
>  
>      my ($vtype, $name, $vmid) = $class->parse_volname($volname);
>      my ($size, undef) = rbd_volume_info($scfg, $storeid, $name);
> -    return $size;
> +    return wantarray ? ($size, 'raw', 0, undef) : $size;

Also, always returning undef for the parent is also not correct for RBD
and ZFS.

>  }
>  
>  sub volume_resize {
> diff --git a/PVE/Storage/ZFSPoolPlugin.pm b/PVE/Storage/ZFSPoolPlugin.pm
> index 9fbd149..90fc576 100644
> --- a/PVE/Storage/ZFSPoolPlugin.pm
> +++ b/PVE/Storage/ZFSPoolPlugin.pm
> @@ -452,7 +452,7 @@ sub volume_size_info {
>      my $attr = $format eq 'subvol' ? 'refquota' : 'volsize';
>      my $value = $class->zfs_get_properties($scfg, $attr, "$scfg->{pool}/$vname");
>      if ($value =~ /^(\d+)$/) {
> -	return $1;
> +	return wantarray ? ($1, $format, 0, undef) : $1;
>      }
>  
>      die "Could not get zfs volume size\n";