1Monitoring::Plugin::GetUospetr(3C)ontributed Perl DocumeMnotnaittioorning::Plugin::Getopt(3)
2
6 Monitoring::Plugin::Getopt - OO perl module providing standardised
7 argument processing for Nagios plugins
8
10 use Monitoring::Plugin::Getopt;
11 # Instantiate object (usage is mandatory)
13 $ng = Monitoring::Plugin::Getopt->new(
14 usage => "Usage: %s -H <host> -w <warning> -c <critical>",
15 version => '0.1',
16 url => 'http://www.openfusion.com.au/labs/nagios/',
17 blurb => 'This plugin tests various stuff.',
18 );
19 # Add argument - named parameters (spec and help are mandatory)
21 $ng->arg(
22 spec => 'critical|c=i',
23 help => q(Exit with CRITICAL status if fewer than INTEGER foobars are free),
24 required => 1,
25 default => 10,
26 );
27 # Add argument - positional parameters - arg spec, help text,
29 # default value, required? (first two mandatory)
30 $ng->arg(
31 'warning|w=i',
32 q(Exit with WARNING status if fewer than INTEGER foobars are free),
33 5,
34 1);
35 # Parse arguments and process standard ones (e.g. usage, help, version)
37 $ng->getopts;
38 # Access arguments using named accessors or or via the generic get()
40 print $ng->opts->warning;
41 print $ng->opts->get('critical');
42
44 Monitoring::Plugin::Getopt is an OO perl module providing standardised
45 and simplified argument processing for Nagios plugins. It implements a
46 number of standard arguments itself (--help, --version, --usage,
47 --timeout, --verbose, and their short form counterparts), produces
48 standardised nagios plugin help output, and allows additional arguments
49 to be easily defined.
50 CONSTRUCTOR
52 # Instantiate object (usage is mandatory)
53 $ng = Monitoring::Plugin::Getopt->new(
54 usage => 'Usage: %s --hello',
55 version => '0.01',
56 );
57 The Monitoring::Plugin::Getopt constructor accepts the following named
59 arguments:
60 usage (required)
62 Short usage message used with --usage/-? and with missing required
63 arguments, and included in the longer --help output. Can include a
64 '%s' sprintf placeholder which will be replaced with the plugin
65 name e.g.
66 usage => qq(Usage: %s -H <hostname> -p <ports> [-v]),
68 might be displayed as:
70 $ ./check_tcp_range --usage
72 Usage: check_tcp_range -H <hostname> -p <ports> [-v]
73 version (required)
75 Plugin version number, included in the --version/-V output, and in
76 the longer --help output. e.g.
77 $ ./check_tcp_range --version
79 check_tcp_range 0.2 [http://www.openfusion.com.au/labs/nagios/]
80 url URL for info about this plugin, included in the --version/-V
82 output, and in the longer --help output (see preceding 'version'
83 example).
84 blurb
86 Short plugin description, included in the longer --help output (see
87 below for an example).
88 license
90 License text, included in the longer --help output (see below for
91 an example). By default, this is set to the standard nagios plugins
92 GPL license text:
93 This nagios plugin is free software, and comes with ABSOLUTELY
95 NO WARRANTY. It may be used, redistributed and/or modified under
96 the terms of the GNU General Public Licence (see
97 http://www.fsf.org/licensing/licenses/gpl.txt).
98 Provide your own to replace this text in the help output.
100 extra
102 Extra text to be appended at the end of the longer --help output.
103 plugin
105 Plugin name. This defaults to the basename of your plugin, which is
106 usually correct, but you can set it explicitly if not.
107 timeout
109 Timeout period in seconds, overriding the standard timeout default
110 (15 seconds).
111 The full --help output has the following form:
113 version string
115 license string
117 blurb
119 usage string
121 options list
123 extra text
125 The 'blurb' and 'extra text' sections are omitted if not supplied. For
127 example:
128 $ ./check_tcp_range -h
130 check_tcp_range 0.2 [http://www.openfusion.com.au/labs/nagios/]
131 This nagios plugin is free software, and comes with ABSOLUTELY NO WARRANTY.
133 It may be used, redistributed and/or modified under the terms of the GNU
134 General Public Licence (see http://www.fsf.org/licensing/licenses/gpl.txt).
135 This plugin tests arbitrary ranges/sets of tcp ports for a host.
137 Usage: check_tcp_range -H <hostname> -p <ports> [-v]
139 Options:
141 -h, --help
142 Print detailed help screen
143 -V, --version
144 Print version information
145 -H, --hostname=ADDRESS
146 Host name or IP address
147 -p, --ports=STRING
148 Port numbers to check. Format: comma-separated, colons for ranges,
149 no spaces e.g. 8700:8705,8710:8715,8760
150 -t, --timeout=INTEGER
151 Seconds before plugin times out (default: 15)
152 -v, --verbose
153 Show details for command-line debugging (can repeat up to 3 times)
154 ARGUMENTS
156 You can define arguments for your plugin using the arg() method, which
157 supports both named and positional arguments. In both cases the "spec"
158 and "help" arguments are required, while the "label", "default", and
159 "required" arguments are optional:
160 # Define --hello argument (named parameters)
162 $ng->arg(
163 spec => 'hello|h=s',
164 help => "Hello string",
165 required => 1,
166 );
167 # Define --hello argument (positional parameters)
169 # Parameter order is 'spec', 'help', 'default', 'required?', 'label'
170 $ng->arg('hello|h=s', "Hello parameter (default %s)", 5, 1);
171 spec
173 The "spec" argument (the first argument in the positional variant)
174 is a Getopt::Long argument specification. See Getopt::Long for the
175 details, but basically it is a series of one or more argument names
176 for this argument (separated by '|'), suffixed with an '=<type>'
177 indicator if the argument takes a value. '=s' indicates a string
178 argument; '=i' indicates an integer argument; appending an '@'
179 indicates multiple such arguments are accepted; appending an '!'
180 indicates negation using '--no'-prefix is possible; and so on. The
181 following are some examples:
182 hello=s
184 hello|h=s
185 ports|port|p=i
186 exclude|X=s@
187 perfdata!
188 verbose|v+
189 help
190 The "help" argument is a string displayed in the --help option list
191 output, or it can be a list (an arrayref) of such strings, for
192 multi-line help (see below).
193 The help string is munged in two ways:
195 • First, if the help string does NOT begins with a '-' sign, it
197 is prefixed by an expanded form of the "spec" argument. For
198 instance, the following hello argument:
199 $ng->arg(
201 spec => 'hello|h=s',
202 help => "Hello string",
203 );
204 would be displayed in the help output as:
206 -h, --hello=STRING
208 Hello string
209 where the '-h, --hello=STRING' part is derived from the spec
211 definition (by convention with short args first, then long,
212 then label/type, if any).
213 • Second, if the string contains a '%s' it will be formatted via
215 "sprintf" with the 'default' as the argument i.e.
216 sprintf($help, $default)
218 Multi-line help is useful in cases where an argument can be of
220 different types and you want to make this explicit in your help
221 output e.g.
222 $ng->arg(
224 spec => 'warning|w=s',
225 help => [
226 'Exit with WARNING status if less than BYTES bytes of disk are free',
227 'Exit with WARNING status if less than PERCENT of disk is free',
228 ],
229 label => [ 'BYTES', 'PERCENT%' ],
230 );
231 would be displayed in the help output as:
233 -w, --warning=BYTES
235 Exit with WARNING status if less than BYTES bytes of disk are free
236 -w, --warning=PERCENT%
237 Exit with WARNING status if less than PERCENT of disk space is free
238 Note that in this case we've also specified explicit labels in
240 another arrayref corresponding to the "help" one - if this had been
241 omitted the types would have defaulted to 'STRING', instead of
242 'BYTES' and 'PERCENT%'.
243 label
245 The "label" argument is a scalar or an arrayref (see 'Multi-line
246 help' description above) that overrides the standard type expansion
247 when generating help text from the spec definition. By default,
248 "spec=i" arguments are labelled as "=INTEGER" in the help text, and
249 "spec=s" arguments are labelled as "=STRING". By supplying your own
250 "label" argument you can override these standard 'INTEGER' and
251 'STRING' designations.
252 For multi-line help, you can supply an ordered list (arrayref) of
254 labels to match the list of help strings e.g.
255 label => [ 'BYTES', 'PERCENT%' ]
257 Any labels that are left as undef (or just omitted, if trailing)
259 will just use the default 'INTEGER' or 'STRING' designations e.g.
260 label => [ undef, 'PERCENT%' ]
262 default
264 The "default" argument is the default value to be given to this
265 parameter if none is explicitly supplied.
266 required
268 The "required" argument is a boolean used to indicate that this
269 argument is mandatory (Monitoring::Plugin::Getopt will exit with
270 your usage message and a 'Missing argument' indicator if any
271 required arguments are not supplied).
272 Note that --help lists your arguments in the order they are defined, so
274 you should order your "arg()" calls accordingly.
275 GETOPTS
277 The main parsing and processing functionality is provided by the
278 getopts() method, which takes no arguments:
279 # Parse and process arguments
281 $ng->getopts;
282 This parses the command line arguments passed to your plugin using
284 Getopt::Long and the builtin and provided argument specifications.
285 Flags and argument values are recorded within the object, and can be
286 accessed either using the generic get() accessor, or using named
287 accessors corresponding to your argument names. For example:
288 print $ng->get('hello');
290 print $ng->hello();
291 if ($ng->verbose) {
293 # ...
294 }
295 if ($ng->get('ports') =~ m/:/) {
297 # ...
298 }
299 Note that where you have defined alternate argument names, the first is
301 considered the citation form. All the builtin arguments are available
302 using their long variant names.
303 BUILTIN PROCESSING
305 The "getopts()" method also handles processing of the immediate builtin
306 arguments, namely --usage, --version, --help, as well as checking all
307 required arguments have been supplied, so you don't have to handle
308 those yourself. This means that your plugin will exit from the
309 getopts() call in these cases - if you want to catch that you can run
310 getopts() within an eval{}.
311 "getopts()" also sets up a default ALRM timeout handler so you can use
313 an
314 alarm $ng->timeout;
316 around any blocking operations within your plugin (which you are free
318 to override if you want to use a custom timeout message).
319
321 Monitoring::Plugin, Getopt::Long
322
324 This code is maintained by the Monitoring Plugin Development Team: see
325 https://monitoring-plugins.org
326 Originally:
328 Gavin Carr <gavin@openfusion.com.au>
329
331 Copyright (C) 2014 by Monitoring Plugin Team Copyright (C)
332 2006-2014 by Nagios Plugin Development Team
333 This library is free software; you can redistribute it and/or modify it
335 under the same terms as Perl itself.
336perl v5.34.0 2021-07-22 Monitoring::Plugin::Getopt(3)