[pve-devel] [PATCH v2 follow up manager 3/5] api: ceph: add endpoint to fetch config keys

[Aaron Lauterer <a.lauterer@proxmox.com>]

This new endpoint allows to get the values of config keys that are
either set in the config db or the ceph.conf file.

Values that are set in the ceph.conf file have priority over values set
in the conifg db via 'ceph config set'.

Expects the --config-keys parameter as a semicolon separated list of
"<section>:<config key>" where the section is a section in the ceph.conf
or config db. For example: global:osd_pool_default_size

Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>
---

I found a small code style issue that was present since the initial
patch. The diff to the original v2 to this follow up is:

--- a/PVE/API2/Ceph/Cfg.pm
+++ b/PVE/API2/Ceph/Cfg.pm
@@ -172,7 +172,7 @@ __PACKAGE__->register_method ({
        my $rados = PVE::RADOS->new();
        my $configdb = $rados->mon_command( { prefix => 'config dump', format => 'json' });
        for my $s (@{$configdb}) {
-           my ($section, $name, $value) = $s ->@{'section', 'name', 'value'};
+           my ($section, $name, $value) = $s->@{'section', 'name', 'value'};
            my $n_section = $normalize->($section);
            my $n_name = $normalize->($name);

 PVE/API2/Ceph/Cfg.pm | 81 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)

diff --git a/PVE/API2/Ceph/Cfg.pm b/PVE/API2/Ceph/Cfg.pm
index a00ef19c..6d05db9c 100644
--- a/PVE/API2/Ceph/Cfg.pm
+++ b/PVE/API2/Ceph/Cfg.pm
@@ -40,6 +40,7 @@ __PACKAGE__->register_method ({
 	my $result = [
 	    { name => 'raw' },
 	    { name => 'db' },
+	    { name => 'value' },
 	];
 
 	return $result;
@@ -114,3 +115,83 @@ __PACKAGE__->register_method ({
 
 	return $res;
     }});
+
+
+my $SINGLE_CONFIGKEY_RE = qr/[0-9a-z\-_\.]+:[0-9a-zA-Z\-_]+/i;
+my $CONFIGKEYS_RE = qr/^(:?${SINGLE_CONFIGKEY_RE})(:?[;, ]${SINGLE_CONFIGKEY_RE})*$/;
+
+__PACKAGE__->register_method ({
+    name => 'value',
+    path => 'value',
+    method => 'GET',
+    proxyto => 'node',
+    protected => 1,
+    permissions => {
+	check => ['perm', '/', [ 'Sys.Audit' ]],
+    },
+    description => "Get configured values from either the config file or config DB.",
+    parameters => {
+	additionalProperties => 0,
+	properties => {
+	    node => get_standard_option('pve-node'),
+	    'config-keys' => {
+		type => "string",
+		typetext => "<section>:<config key>[;<section>:<config key>]",
+		pattern => $CONFIGKEYS_RE,
+		description => "List of <section>:<config key> items.",
+	    }
+	},
+    },
+    returns => {
+	type => 'object',
+	description => "Contains {section}->{key} children with the values",
+    },
+    code => sub {
+	my ($param) = @_;
+
+	PVE::Ceph::Tools::check_ceph_inited();
+
+	# Ceph treats '-' and '_' the same in parameter names, stick with '-'
+	my $normalize = sub {
+	    my $t = shift;
+	    $t =~ s/_/-/g;
+	    return $t;
+	};
+
+	my $requested_keys = {};
+	for my $pair (PVE::Tools::split_list($param->{'config-keys'})) {
+	    my ($section, $key) = split(":", $pair);
+	    $section = $normalize->($section);
+	    $key = $normalize->($key);
+
+	    $requested_keys->{$section}->{$key} = 1;
+	}
+
+	my $config = {};
+
+	my $rados = PVE::RADOS->new();
+	my $configdb = $rados->mon_command( { prefix => 'config dump', format => 'json' });
+	for my $s (@{$configdb}) {
+	    my ($section, $name, $value) = $s->@{'section', 'name', 'value'};
+	    my $n_section = $normalize->($section);
+	    my $n_name = $normalize->($name);
+
+	    $config->{$n_section}->{$n_name} = $value
+		if defined $requested_keys->{$n_section} && $n_name eq $n_name;
+	}
+
+	# read ceph.conf after config db as it has priority if settings are present in both
+	my $config_file = cfs_read_file('ceph.conf');
+	for my $section (keys %{$config_file}) {
+	    my $n_section = $normalize->($section);
+	    next if !defined $requested_keys->{$n_section};
+
+	    for my $key (keys %{$config_file->{$section}}) {
+		my $n_key = $normalize->($key);
+		$config->{$n_section}->{$n_key} = $config_file->{$section}->{$key}
+		    if $requested_keys->{$n_section}->{$n_key};
+	    }
+	}
+
+	return $config;
+    }});
-- 
2.30.2