Jobs/VZDump: encode/decode 'prune-backups' where needed

we want to write it out to the config as propertyString,
but want it as object in the api (for compatiblity)

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

PVE/Jobs/Plugin.pm

@@ -52,6 +52,21 @@ sub parse_config {
    return $cfg;
 }
 
+# call the plugin specific decode/encode code
+sub decode_value {
+    my ($class, $type, $key, $value) = @_;
+
+    my $plugin = __PACKAGE__->lookup($type);
+    return $plugin->decode_value($type, $key, $value);
+}
+
+sub encode_value {
+    my ($class, $type, $key, $value) = @_;
+
+    my $plugin = __PACKAGE__->lookup($type);
+    return $plugin->encode_value($type, $key, $value);
+}
+
 sub run {
     my ($class, $cfg) = @_;
     # implement in subclass

PVE/Jobs/VZDump.pm

@@ -7,6 +7,7 @@ use PVE::INotify;
 use PVE::VZDump::Common;
 use PVE::API2::VZDump;
 use PVE::Cluster;
+use PVE::JSONSchema;
 
 use base qw(PVE::Jobs::Plugin);
 
@@ -36,6 +37,32 @@ sub options {
     return $options;
 }
 
+sub decode_value {
+    my ($class, $type, $key, $value) = @_;
+
+    if ($key eq 'prune-backups' && !ref($value)) {
+	$value = PVE::JSONSchema::parse_property_string(
+	    'prune-backups',
+	    $value,
+	);
+    }
+
+    return $value;
+}
+
+sub encode_value {
+    my ($class, $type, $key, $value) = @_;
+
+    if ($key eq 'prune-backups' && ref($value) eq 'HASH') {
+	$value = PVE::JSONSchema::print_property_string(
+	    $value,
+	    'prune-backups',
+	);
+    }
+
+    return $value;
+}
+
 sub run {
     my ($class, $conf) = @_;