1 package Collectd::Unixsock;
5 Collectd::Unixsock - Abstraction layer for accessing the functionality by collectd's unixsock plugin.
9 use Collectd::Unixsock ();
11 my $sock = Collectd::Unixsock->new ($path);
13 my $value = $sock->getval (%identifier);
14 $sock->putval (%identifier,
16 values => [123, 234, 345]);
22 collectd's unixsock plugin allows external programs to access the values it has
23 collected or received and to submit own values. This Perl-module is simply a
24 little abstraction layer over this interface to make it even easier for
25 programmers to interact with the daemon.
32 use Carp (qw(cluck confess));
34 use Regexp::Common (qw(number));
41 my $sock = IO::Socket::UNIX->new (Type => SOCK_STREAM, Peer => $path);
44 cluck ("Cannot open UNIX-socket $path: $!");
50 =head1 VALUE IDENTIFIER
52 The values in the collectd are identified using an five-tupel (host, plugin,
53 plugin-instance, type, type-instance) where only plugin-instance and
54 type-instance may be NULL (or undefined). Many functions expect an
55 I<%identifier> hash that has at least the members B<host>, B<plugin>, and
56 B<type>, possibly completed by B<plugin_instance> and B<type_instance>.
58 Usually you can pass this hash as follows:
60 $obj->method (host => $host, plugin => $plugin, type => $type, %other_args);
64 sub _create_identifier
71 if (!$args->{'host'} || !$args->{'plugin'} || !$args->{'type'})
73 cluck ("Need `host', `plugin' and `type'");
77 $host = $args->{'host'};
78 $plugin = $args->{'plugin'};
79 $plugin .= '-' . $args->{'plugin_instance'} if (defined ($args->{'plugin_instance'}));
80 $type = $args->{'type'};
81 $type .= '-' . $args->{'type_instance'} if (defined ($args->{'type_instance'}));
83 return ("$host/$plugin/$type");
84 } # _create_identifier
96 ($host, $plugin, $type) = split ('/', $string);
98 ($plugin, $plugin_instance) = split ('-', $plugin, 2);
99 ($type, $type_instance) = split ('-', $type, 2);
107 $ident->{'plugin_instance'} = $plugin_instance if (defined ($plugin_instance));
108 $ident->{'type_instance'} = $type_instance if (defined ($type_instance));
111 } # _parse_identifier
113 =head1 PUBLIC METHODS
117 =item I<$obj> = Collectd::Unixsock->B<new> ([I<$path>]);
119 Creates a new connection to the daemon. The optional I<$path> argument gives
120 the path to the UNIX socket of the C<unixsock plugin> and defaults to
121 F</var/run/collectd-unixsock>. Returns the newly created object on success and
129 my $path = @_ ? shift : '/var/run/collectd-unixsock';
130 my $sock = _create_socket ($path) or return;
140 =item I<$res> = I<$obj>-E<gt>B<getval> (I<%identifier>);
142 Requests a value-list from the daemon. On success a hash-ref is returned with
143 the name of each data-source as the key and the according value as, well, the
144 value. On error false is returned.
154 my $fh = $obj->{'sock'} or confess;
160 $identifier = _create_identifier (\%args) or return;
162 $msg = "GETVAL $identifier\n";
164 send ($fh, $msg, 0) or confess ("send: $!");
167 recv ($fh, $msg, 1024, 0) or confess ("recv: $!");
170 ($status, $msg) = split (' ', $msg, 2);
173 $obj->{'error'} = $msg;
177 for (split (' ', $msg))
180 if ($entry =~ m/^(\w+)=NaN$/)
184 elsif ($entry =~ m/^(\w+)=($RE{num}{real})$/)
186 $ret->{$1} = 0.0 + $2;
193 =item I<$obj>-E<gt>B<putval> (I<%identifier>, B<time> => I<$time>, B<values> => [...]);
195 Submits a value-list to the daemon. If the B<time> argument is omitted
196 C<time()> is used. The requierd argument B<values> is a reference to an array
197 of values that is to be submitted. The number of values must match the number
198 of values expected for the given B<type> (see L<VALUE IDENTIFIER>), though this
199 is checked by the daemon, not the Perl module. Also, gauge data-sources
200 (e.E<nbsp>g. system-load) may be C<undef>. Returns true upon success and false
211 my $fh = $obj->{'sock'} or confess;
216 $identifier = _create_identifier (\%args) or return;
217 if (!$args{'values'})
219 cluck ("Need argument `values'");
223 if (!ref ($args{'values'}))
225 $values = $args{'values'};
229 my $time = $args{'time'} ? $args{'time'} : time ();
230 $values = join (':', $time, map { defined ($_) ? $_ : 'U' } (@{$args{'values'}}));
233 $msg = "PUTVAL $identifier $values\n";
235 send ($fh, $msg, 0) or confess ("send: $!");
237 recv ($fh, $msg, 1024, 0) or confess ("recv: $!");
240 ($status, $msg) = split (' ', $msg, 2);
241 return (1) if ($status == 0);
243 $obj->{'error'} = $msg;
247 =item I<$res> = I<$obj>-E<gt>B<listval> ()
249 Queries a list of values from the daemon. The list is returned as an array of
250 hash references, where each hash reference is a valid identifier. The C<time>
251 member of each hash holds the epoch value of the last update of that value.
261 my $fh = $obj->{'sock'} or confess;
264 send ($fh, $msg, 0) or confess ("send: $!");
267 ($status, $msg) = split (' ', $msg, 2);
270 $obj->{'error'} = $msg;
274 for (my $i = 0; $i < $status; $i++)
282 ($time, $ident) = split (' ', $msg, 2);
284 $ident = _parse_identifier ($ident);
285 $ident->{'time'} = int ($time);
288 } # for (i = 0 .. $status)
293 =item I<$obj>-E<gt>destroy ();
295 Closes the socket before the object is destroyed. This function is also
296 automatically called then the object goes out of scope.
307 close ($obj->{'sock'});
308 delete ($obj->{'sock'});
320 Florian octo Forster E<lt>octo@verplant.orgE<gt>