Re: [pve-devel] [PATCH guest-common v8 2/7] add Dir mapping config

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

Am 08.11.23 um 09:52 schrieb Markus Frank:
> Adds a config file for directories by using a 'map'
> array propertystring for each node mapping.
> 
> Next to node & path, there is the optional
> submounts parameter in the map array.
> Additionally there are the default settings for xattr & acl.
> 
> example config:
> ```
> some-dir-id
> 	map node=node1,path=/mnt/share/,submounts=1
> 	map node=node2,path=/mnt/share/,
> 	xattr 1
> 	acl 1
> ```
> 
> Signed-off-by: Markus Frank <m.frank@proxmox.com>
> ---
>  src/Makefile           |   1 +
>  src/PVE/Mapping/Dir.pm | 177 +++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 178 insertions(+)
>  create mode 100644 src/PVE/Mapping/Dir.pm
> 

> diff --git a/src/PVE/Mapping/Dir.pm b/src/PVE/Mapping/Dir.pm
> new file mode 100644
> index 0000000..6c87073
> --- /dev/null
> +++ b/src/PVE/Mapping/Dir.pm
> @@ -0,0 +1,177 @@
> +package PVE::Mapping::Dir;
> +
> +use strict;
> +use warnings;
> +
> +use PVE::Cluster qw(cfs_register_file cfs_read_file cfs_lock_file cfs_write_file);
> +use PVE::JSONSchema qw(get_standard_option parse_property_string);
> +use PVE::SectionConfig;
> +use PVE::INotify;

Nit: not sorted alphabetically

---snip---

> +my $map_fmt = {
> +    node => get_standard_option('pve-node'),
> +    path => {
> +	description => "Directory-path that should be shared with the guest.",

Nit: space instead of - is nicer IMHO and since it's an absolute path
"Absolute directory path"

> +	type => 'string',
> +	format => 'pve-storage-path',

This is registered in PVE/Storage/Plugin.pm
To be clean, we should either add an include here (guest-common already
depends on libpve-storage) or move registering the format to PVE::JSONSchema

> +    },
> +    submounts => {
> +	type => 'boolean',
> +	description => "Option to tell the guest which directories are mount points.",

I haven't looked at the code where this is used yet, so I'm as confused
as a user now ;) Does this affect mount points within the directory
(which the "sub" prefix suggests)? But it's a boolean, so how can I tell
"which directories"? The description should answer: When does it need to
be set/what effect does it have?

> +	optional => 1,
> +    },
> +    description => {
> +	description => "Description of the node specific directory.",
> +	type => 'string',
> +	optional => 1,
> +	maxLength => 4096,
> +    },
> +};
> +
> +my $defaultData = {
> +    propertyList => {
> +        id => {
> +            type => 'string',
> +            description => "The ID of the directory",
> +            format => 'pve-configid',
> +        },
> +        description => {
> +            description => "Description of the directory",
> +            type => 'string',
> +            optional => 1,
> +            maxLength => 4096,
> +        },
> +        map => {
> +            type => 'array',
> +            description => 'A list of maps for the cluster nodes.',
> +	    optional => 1,
> +            items => {
> +                type => 'string',
> +                format => $map_fmt,
> +            },
> +        },

Style nit: Indentation is mostly wrong since the beginning of
$defaultData until here.

> +	xattr => {
> +	    type => 'boolean',
> +	    description => "Enable support for extended attributes.",
> +	    optional => 1,
> +	},
> +	acl => {
> +	    type => 'boolean',
> +	    description => "Enable support for posix ACLs (implies --xattr).",

s/posix/POSIX/

> +	    optional => 1,

What could also be mentioned for xattr and acl: do the underlying file
systems need to support these? What happens if they don't?

> +	},
> +    },
> +};
> +
> +sub private {
> +    return $defaultData;
> +}
> +
> +sub options {
> +    return {
> +        description => { optional => 1 },
> +        map => {},
> +        xattr => { optional => 1 },
> +        acl => { optional => 1 },

Style nit: wrong indentation

> +    };
> +}
> +
> +sub assert_valid {
> +    my ($dir_cfg) = @_;
> +
> +    my $path = $dir_cfg->{path};
> +
> +    if (! -e $path) {
> +        die "Path $path does not exist\n";

Style nit: wrong indentation

> +    }
> +    if ((-e $path) && (! -d $path)) {

Style nit: could be made into an elsif to avoid an extra -e check

> +        die "Path $path exists but is not a directory\n"

Style nit: wrong indentation

> +    }
> +
> +    return 1;
> +};
> +
> +sub config {
> +    return cfs_read_file($FILENAME);
> +}
> +
> +sub lock_dir_config {
> +    my ($code, $errmsg) = @_;
> +
> +    cfs_lock_file($FILENAME, undef, $code);
> +    my $err = $@;
> +    if ($err) {

Style nit: could be if (my $err = $@) {

> +        $errmsg ? die "$errmsg: $err" : die $err;

Style nit: wrong indentation

> +    }
> +}
> +
> +sub write_dir_config {
> +    my ($cfg) = @_;
> +
> +    cfs_write_file($FILENAME, $cfg);
> +}
> +
> +sub find_on_current_node {
> +    my ($id) = @_;
> +
> +    my $cfg = config();
> +    my $node = PVE::INotify::nodename();
> +
> +    return get_node_mapping($cfg, $id, $node);
> +}
> +
> +sub get_node_mapping {
> +    my ($cfg, $id, $nodename) = @_;
> +
> +    return undef if !defined($cfg->{ids}->{$id});
> +
> +    my $res = [];
> +    my $mapping_list = $cfg->{ids}->{$id}->{map};
> +    foreach my $map (@{$mapping_list}) {

Style nit: new code should use "for"

> +	my $entry = eval { parse_property_string($map_fmt, $map) };
> +	warn $@ if $@;
> +	if ($entry && $entry->{node} eq $nodename) {
> +	    push $res->@*, $entry;
> +	}
> +    }
> +    return $res;
> +}
> +
> +PVE::Mapping::Dir->register();
> +PVE::Mapping::Dir->init();
> +
> +1;