Monitoring::Livestatus(3pm)

NAME
Monitoring::Livestatus - Perl API for check_mk livestatus to access runtime data from Nagios and Icinga

SYNOPSIS
    use Monitoring::Livestatus;
    my $ml = Monitoring::Livestatus->new(
      socket => '/var/lib/livestatus/livestatus.sock'
    );
    my $hosts = $ml->selectall_arrayref("GET hosts");

DESCRIPTION
This module connects via socket/tcp to the livestatus addon for Naemon, Nagios, Icinga and Shinken. You first have to install and activate the livestatus addon in your monitoring installation.

CONSTRUCTOR

  new ( [ARGS] )
Creates an "Monitoring::Livestatus" object. "new" takes at least the socketpath. Arguments are in key-value pairs.

socket
    path to the UNIX socket of check_mk livestatus

server
    uses this server for a TCP connection

peer
    alternative way to set socket or server, if value contains ':' server is used, else socket

name
    human readable name for this connection, defaults to the the socket/server address

verbose
    verbose mode

line_separator
    ascii code of the line separator, defaults to 10, (newline)

column_separator
    ascii code of the column separator, defaults to 0 (null byte)

list_separator
    ascii code of the list separator, defaults to 44 (comma)

host_service_separator
    ascii code of the host/service separator, defaults to 124 (pipe)

keepalive
    enable keepalive. Default is off

errors_are_fatal
    errors will die with an error message. Default: on

warnings
    show warnings currently only querys without Columns: Header will result in a warning

timeout
    set a general timeout. Used for connect and querys, no default

query_timeout
    set a query timeout. Used for retrieving querys, Default 60sec

connect_timeout
    set a connect timeout. Used for initial connections, default 5sec

If the constructor is only passed a single argument, it is assumed to be a the "peer" specification. Use either socker OR server.

METHODS

  do
 do($statement)
 do($statement, %opts)

Send a single statement without fetching the result. Always returns true.

  selectall_arrayref
 selectall_arrayref($statement)
 selectall_arrayref($statement, %opts)
 selectall_arrayref($statement, %opts, $limit )

Sends a query and returns an array reference of arrays

    my $arr_refs = $ml->selectall_arrayref("GET hosts");

to get an array of hash references do something like

    my $hash_refs = $ml->selectall_arrayref(
      "GET hosts", { Slice => {} }
    );

to get an array of hash references from the first 2 returned rows only

    my $hash_refs = $ml->selectall_arrayref(
      "GET hosts", { Slice => {} }, 2
    );

you may use limit to limit the result to this number of rows

column aliases can be defined with a rename hash

    my $hash_refs = $ml->selectall_arrayref(
      "GET hosts", {
        Slice => {},
        rename => {
          'name' => 'host_name'
        }
      }
    );

  selectall_hashref
 selectall_hashref($statement, $key_field)
 selectall_hashref($statement, $key_field, %opts)

Sends a query and returns a hashref with the given key

    my $hashrefs = $ml->selectall_hashref("GET hosts", "name");

  selectcol_arrayref
 selectcol_arrayref($statement)
 selectcol_arrayref($statement, %opt )

Sends a query an returns an arrayref for the first columns

    my $array_ref = $ml->selectcol_arrayref("GET hosts\nColumns: name");

    $VAR1 = [
              'localhost',
              'gateway',
            ];

returns an empty array if nothing was found

to get a different column use this

    my $array_ref = $ml->selectcol_arrayref(
       "GET hosts\nColumns: name contacts",
       { Columns => [2] }
    );

 you can link 2 columns in a hash result set

    my %hash = @{
      $ml->selectcol_arrayref(
        "GET hosts\nColumns: name contacts",
        { Columns => [1,2] }
      )
    };

produces a hash with host the contact assosiation

    $VAR1 = {
              'localhost' => 'user1',
              'gateway'   => 'user2'
            };

  selectrow_array
 selectrow_array($statement)
 selectrow_array($statement, %opts)

Sends a query and returns an array for the first row

    my @array = $ml->selectrow_array("GET hosts");

returns undef if nothing was found

  selectrow_arrayref
 selectrow_arrayref($statement)
 selectrow_arrayref($statement, %opts)

Sends a query and returns an array reference for the first row

    my $arrayref = $ml->selectrow_arrayref("GET hosts");

returns undef if nothing was found

  selectrow_hashref
 selectrow_hashref($statement)
 selectrow_hashref($statement, %opt)

Sends a query and returns a hash reference for the first row

    my $hashref = $ml->selectrow_hashref("GET hosts");

returns undef if nothing was found

  selectscalar_value
 selectscalar_value($statement)
 selectscalar_value($statement, %opt)

Sends a query and returns a single scalar

    my $count = $ml->selectscalar_value("GET hosts\nStats: state = 0");

returns undef if nothing was found

  errors_are_fatal
 errors_are_fatal()
 errors_are_fatal($value)

Enable or disable fatal errors. When enabled the module will confess on any error.

returns the current setting if called without new value

  warnings
 warnings()
 warnings($value)

Enable or disable warnings. When enabled the module will carp on warnings.

returns the current setting if called without new value

  verbose
 verbose()
 verbose($values)

Enable or disable verbose output. When enabled the module will dump out debug output

returns the current setting if called without new value

  peer_addr
 $ml->peer_addr()

returns the current peer address

when using multiple backends, a list of all addresses is returned in list context

  peer_name
 $ml->peer_name()
 $ml->peer_name($string)

if new value is set, name is set to this value

always returns the current peer name

when using multiple backends, a list of all names is returned in list context

  peer_key
 $ml->peer_key()

returns a uniq key for this peer

  post_processing
 $ml->post_processing($result, $options, $keys)

returns postprocessed result.

Useful when using select based io.

QUERY OPTIONS
In addition to the normal query syntax from the livestatus addon, it is possible to set column aliases in various ways.

  AddPeer
adds the peers name, addr and key to the result set:

 my $hosts = $ml->selectall_hashref(
   "GET hosts\nColumns: name alias state",
   "name",
   { AddPeer => 1 }
 );

  Backend
send the query only to some specific backends. Only useful when using multiple backends.

 my $hosts = $ml->selectall_arrayref(
   "GET hosts\nColumns: name alias state",
   { Backends => [ 'key1', 'key4' ] }
 );

  Columns
    only return the given column indexes

    my $array_ref = $ml->selectcol_arrayref(
       "GET hosts\nColumns: name contacts",
       { Columns => [2] }
    );

  see L<selectcol_arrayref> for more examples

  Deepcopy
    deep copy/clone the result set.

    Only effective when using multiple backends and threads.
    This can be safely turned off if you don't change the
    result set.
    If you get an error like "Invalid value for shared scalar" error" this
    should be turned on.

    my $array_ref = $ml->selectcol_arrayref(
       "GET hosts\nColumns: name contacts",
       { Deepcopy => 1 }
    );

  Limit
    Just like the Limit: <nr> option from livestatus itself.
    In addition you can add a start,length limit.

    my $array_ref = $ml->selectcol_arrayref(
       "GET hosts\nColumns: name contacts",
       { Limit => "10,20" }
    );

    This example will return 20 rows starting at row 10. You will
    get row 10-30.

    Cannot be combined with a Limit inside the query
    because a Limit will be added automatically.

    Adding a limit this way will greatly increase performance and
    reduce memory usage.

    This option is multibackend safe contrary to the "Limit: " part of a statement.
    Sending a statement like "GET...Limit: 10" with 3 backends will result in 30 rows.
    Using this options, you will receive only the first 10 rows.

  Rename
  see L<COLUMN ALIAS> for detailed explainaton

  Slice
  see L<selectall_arrayref> for detailed explainaton

  Sum
The Sum option only applies when using multiple backends. The values from all backends with be summed up to a total.

 my $stats = $ml->selectrow_hashref(
   "GET hosts\nStats: state = 0\nStats: state = 1",
   { Sum => 1 }
 );

COLUMN ALIAS
In addition to the normal query syntax from the livestatus addon, it is possible to set column aliases in various ways.

A valid Columns: Header could look like this:

 my $hosts = $ml->selectall_arrayref(
   "GET hosts\nColumns: state as status"
 );

Stats queries could be aliased too:

 my $stats = $ml->selectall_arrayref(
   "GET hosts\nStats: state = 0 as up"
 );

This syntax is available for: Stats, StatsAnd, StatsOr and StatsGroupBy

An alternative way to set column aliases is to define rename option key/value pairs:

 my $hosts = $ml->selectall_arrayref(
   "GET hosts\nColumns: name", {
     rename => { 'name' => 'hostname' }
   }
 );

  extract_keys_from_stats_statement
 extract_keys_from_stats_statement($statement)

Extract column keys from statement.

ERROR HANDLING
Errorhandling can be done like this:

    use Monitoring::Livestatus;
    my $ml = Monitoring::Livestatus->new(
      socket => '/var/lib/livestatus/livestatus.sock'
    );
    $ml->errors_are_fatal(0);
    my $hosts = $ml->selectall_arrayref("GET hosts");
    if($Monitoring::Livestatus::ErrorCode) {
        confess($Monitoring::Livestatus::ErrorMessage);
    }

SEE ALSO
For more information about the query syntax and the livestatus plugin installation see the Livestatus page: http://mathias-kettner.de/checkmk_livestatus.html

AUTHOR
Sven Nierlein, 2009-present, <sven@nierlein.org>

COPYRIGHT AND LICENSE
Copyright (C) by Sven Nierlein

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.