1 package NPTest;
3 #
4 # Helper Functions for testing Nagios Plugins
5 #
7 require Exporter;
8 @ISA = qw(Exporter);
9 @EXPORT = qw(getTestParameter checkCmd skipMissingCmd);
10 @EXPORT_OK = qw(DetermineTestHarnessDirectory TestsFrom SetCacheFilename);
12 use strict;
13 use warnings;
15 use Cwd;
16 use File::Basename;
18 use IO::File;
19 use Data::Dumper;
21 use Test;
23 use vars qw($VERSION);
24 $VERSION = do { my @r = (q$Revision$ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r }; # must be all one line, for MakeMaker
26 =head1 NAME
28 NPTest - Simplify the testing of Nagios Plugins
30 =head1 DESCRIPTION
32 This modules provides convenience functions to assist in the testing
33 of Nagios Plugins, making the testing code easier to read and write;
34 hopefully encouraging the development of a more complete test suite for
35 the Nagios Plugins. It is based on the patterns of testing seen in the
36 1.4.0 release, and continues to use the L<Test> module as the basis of
37 testing.
39 =head1 FUNCTIONS
41 This module defines three public functions, C<getTestParameter(...)>,
42 C<checkCmd(...)> and C<skipMissingCmd(...)>. These are exported by
43 default via the C<use NPTest;> statement.
45 =over
47 =item C<getTestParameter(...)>
49 A flexible and user override-able method of collecting, storing and
50 retrieving test parameters. This function allows the test harness
51 developer to interactively request test parameter information from the
52 user, when the no means of obtaining the information automatically has
53 been successful. The user is provided with the option of accepting
54 test harness developer's default value for the parameter, if a suggested
55 default is provided.
57 User supplied responses are stored in an external (file-based)
58 cache. These values are retrieved on subsequent runs alleviating the
59 user of reconfirming the previous entered responses. The user is able
60 to override the value of a parameter on any given run by setting the
61 associated environment variable. These environment variable based
62 overrides are not stored in the cache, allowing one-time and what-if
63 based tests on the command line without polluting the cache.
65 The option exists to store parameters in a scoped means, allowing a
66 test harness to a localise a parameter should the need arise. This
67 allows a parameter of the same name to exist in a test harness
68 specific scope, while not affecting the globally scoped parameter. The
69 scoping identifier is the name of the test harness sans the trailing
70 ".t". All cache searches first look to a scoped parameter before
71 looking for the parameter at global scope. Thus for a test harness
72 called "check_disk.t" requesting the parameter "mountpoint_valid", the
73 cache is first searched for "check_disk"/"mountpoint_valid", if this
74 fails, then a search is conducted for "mountpoint_valid".
76 The facilitate quick testing setup, it is possible to accept all the
77 developer provided defaults by setting the environment variable
78 "NPTEST_ACCEPTDEFAULT" to "1" (or any other perl truth value). Note
79 that, such defaults are not stored in the cache, as there is currently
80 no mechanism to edit existing cache entries, save the use of text
81 editor or removing the cache file completely.
83 =item C<testCmd($command)>
85 Call with NPTest->testCmd("./check_disk ...."). This returns a NPTest object
86 which you can then run $object->return_code or $object->output against.
88 Testing of results would be done in your test script, not in this module.
90 =item C<checkCmd(...)>
92 This function is obsolete. Use C<testCmd()> instead.
94 This function attempts to encompass the majority of test styles used
95 in testing Nagios Plugins. As each plug-in is a separate command, the
96 typical tests we wish to perform are against the exit status of the
97 command and the output (if any) it generated. Simplifying these tests
98 into a single function call, makes the test harness easier to read and
99 maintain and allows additional functionality (such as debugging) to be
100 provided without additional effort on the part of the test harness
101 developer.
103 It is possible to enable debugging via the environment variable
104 C<NPTEST_DEBUG>. If this environment variable exists and its value in PERL's
105 boolean context evaluates to true, debugging is enabled.
107 The function prototype can be expressed as follows:
109 Parameter 1 : command => DEFINED SCALAR(string)
110 Parameter 2 : desiredExitStatus => ONE OF
111 SCALAR(integer)
112 ARRAYREF(integer)
113 HASHREF(integer,string)
114 UNDEFINED
115 Parameter 3 : desiredOutput => SCALAR(string) OR UNDEFINED
116 Parameter 4 : exceptions => HASH(integer,string) OR UNDEFINED
117 Returns : SCALAR(integer) as defined by Test::ok(...)
119 The function treats the first parameter C<$command> as a command line
120 to execute as part of the test, it is executed only once and its exit
121 status (C<$?E<gt>E<gt>8>) and output are captured.
123 At this point if debugging is enabled the command, its exit status and
124 output are displayed to the tester.
126 C<checkCmd(...)> allows the testing of either the exit status or the
127 generated output or both, not testing either will result in neither
128 the C<Test::ok(...)> or C<Test::skip(...)> functions being called,
129 something you probably don't want. Note that each defined test
130 (C<$desiredExitStatus> and C<$desiredOutput>) results in a invocation
131 of either C<Test::ok(...)> or C<Test::skip(...)>, so remember this
132 when counting the number of tests to place in the C<Test::plan(...)>
133 call.
135 Many Nagios Plugins test network services, some of which may not be
136 present on all systems. To cater for this, C<checkCmd(...)> allows the
137 tester to define exceptions based on the command's exit status. These
138 exceptions are provided to skip tests if the test case developer
139 believes the service is not being provided. For example, if a site
140 does not have a POP3 server, the test harness could map the
141 appropriate exit status to a useful message the person running the
142 tests, telling the reason the test is being skipped.
144 Example:
146 my %exceptions = ( 2 =E<gt> "No POP Server present?" );
148 $t += checkCmd( "./check_pop I<some args>", 0, undef, %exceptions );
150 Thus, in the above example, an exit status of 2 does not result in a
151 failed test case (as the exit status is not the desired value of 0),
152 but a skipped test case with the message "No POP Server present?"
153 given as the reason.
155 Sometimes the exit status of a command should be tested against a set
156 of possible values, rather than a single value, this could especially
157 be the case in failure testing. C<checkCmd(...)> support two methods
158 of testing against a set of desired exit status values.
160 =over
162 =item *
164 Firstly, if C<$desiredExitStatus> is a reference to an array of exit
165 stati, if the actual exit status of the command is present in the
166 array, it is used in the call to C<Test::ok(...)> when testing the
167 exit status.
169 =item *
171 Alternatively, if C<$desiredExitStatus> is a reference to a hash of
172 exit stati (mapped to the strings "continue" or "skip"), similar
173 processing to the above occurs with the side affect of determining if
174 any generated output testing should proceed. Note: only the string
175 "skip" will result in generated output testing being skipped.
177 =back
179 =item C<skipMissingCmd(...)>
181 If a command is missing and the test harness must C<Test::skip()> some
182 or all of the tests in a given test harness this function provides a
183 simple iterator to issue an appropriate message the requested number
184 of times.
186 =back
188 =head1 SEE ALSO
190 L<Test>
192 The rest of the code, as I have only commented on the major public
193 functions that test harness writers will use, not all the code present
194 in this helper module.
196 =head1 AUTHOR
198 Copyright (c) 2005 Peter Bray. All rights reserved.
200 This package is free software and is provided "as is" without express
201 or implied warranty. It may be used, redistributed and/or modified
202 under the same terms as the Nagios Plugins release.
204 =cut
206 #
207 # Package Scope Variables
208 #
210 my( %CACHE ) = ();
212 # I'm not really sure wether to house a site-specific cache inside
213 # or outside of the extracted source / build tree - lets default to outside
214 my( $CACHEFILENAME ) = ( exists( $ENV{'NPTEST_CACHE'} ) && $ENV{'NPTEST_CACHE'} )
215 ? $ENV{'NPTEST_CACHE'} : "/var/tmp/NPTest.cache"; # "../Cache.pdd";
217 #
218 # Testing Functions
219 #
221 sub checkCmd
222 {
223 my( $command, $desiredExitStatus, $desiredOutput, %exceptions ) = @_;
225 my $result = NPTest->testCmd($command);
227 my $output = $result->output;
228 my $exitStatus = $result->return_code;
230 $output = "" unless defined( $output );
231 chomp( $output );
233 my $testStatus;
235 my $testOutput = "continue";
237 if ( defined( $desiredExitStatus ) )
238 {
239 if ( ref $desiredExitStatus eq "ARRAY" )
240 {
241 if ( scalar( grep { $_ == $exitStatus } @{$desiredExitStatus} ) )
242 {
243 $desiredExitStatus = $exitStatus;
244 }
245 else
246 {
247 $desiredExitStatus = -1;
248 }
249 }
250 elsif ( ref $desiredExitStatus eq "HASH" )
251 {
252 if ( exists( ${$desiredExitStatus}{$exitStatus} ) )
253 {
254 if ( defined( ${$desiredExitStatus}{$exitStatus} ) )
255 {
256 $testOutput = ${$desiredExitStatus}{$exitStatus};
257 }
258 $desiredExitStatus = $exitStatus;
259 }
260 else
261 {
262 $desiredExitStatus = -1;
263 }
264 }
266 if ( %exceptions && exists( $exceptions{$exitStatus} ) )
267 {
268 $testStatus += skip( $exceptions{$exitStatus}, $exitStatus, $desiredExitStatus );
269 $testOutput = "skip";
270 }
271 else
272 {
273 $testStatus += ok( $exitStatus, $desiredExitStatus );
274 }
275 }
277 if ( defined( $desiredOutput ) )
278 {
279 if ( $testOutput ne "skip" )
280 {
281 $testStatus += ok( $output, $desiredOutput );
282 }
283 else
284 {
285 $testStatus += skip( "Skipping output test as requested", $output, $desiredOutput );
286 }
287 }
289 return $testStatus;
290 }
293 sub skipMissingCmd
294 {
295 my( $command, $count ) = @_;
297 my $testStatus;
299 for ( 1 .. $count )
300 {
301 $testStatus += skip( "Missing ${command} - tests skipped", 1 );
302 }
304 return $testStatus;
305 }
307 sub getTestParameter
308 {
309 my( $param, $envvar, $default, $brief, $scoped ) = @_;
311 # Apply default values for optional arguments
312 $scoped = ( defined( $scoped ) && $scoped );
314 my $testharness = basename( (caller(0))[1], ".t" ); # used for scoping
316 if ( defined( $envvar ) && exists( $ENV{$envvar} ) && $ENV{$envvar} )
317 {
318 return $ENV{$envvar};
319 }
321 my $cachedValue = SearchCache( $param, $testharness );
322 if ( defined( $cachedValue ) && $cachedValue )
323 {
324 return $cachedValue;
325 }
327 my $defaultValid = ( defined( $default ) && $default );
328 my $autoAcceptDefault = ( exists( $ENV{'NPTEST_ACCEPTDEFAULT'} ) && $ENV{'NPTEST_ACCEPTDEFAULT'} );
330 if ( $autoAcceptDefault && $defaultValid )
331 {
332 return $default;
333 }
335 my $userResponse = "";
337 while ( $userResponse eq "" )
338 {
339 print STDERR "\n";
340 print STDERR "Test Harness : $testharness\n";
341 print STDERR "Test Parameter : $param\n";
342 print STDERR "Environment Variable : $envvar\n";
343 print STDERR "Brief Description : $brief\n";
344 print STDERR "Enter value ", ($defaultValid ? "[${default}]" : "[]"), " => ";
345 $userResponse = <STDIN>;
346 $userResponse = "" if ! defined( $userResponse ); # Handle EOF
347 chomp( $userResponse );
348 if ( $defaultValid && $userResponse eq "" )
349 {
350 $userResponse = $default;
351 }
352 }
354 print STDERR "\n";
356 # define all user responses at global scope
357 SetCacheParameter( $param, ( $scoped ? $testharness : undef ), $userResponse );
359 return $userResponse;
360 }
362 #
363 # Internal Cache Management Functions
364 #
366 sub SearchCache
367 {
368 my( $param, $scope ) = @_;
370 LoadCache();
372 if ( exists( $CACHE{$scope} ) && exists( $CACHE{$scope}{$param} ) )
373 {
374 return $CACHE{$scope}{$param};
375 }
377 if ( exists( $CACHE{$param} ) )
378 {
379 return $CACHE{$param};
380 }
381 }
383 sub SetCacheParameter
384 {
385 my( $param, $scope, $value ) = @_;
387 if ( defined( $scope ) )
388 {
389 $CACHE{$scope}{$param} = $value;
390 }
391 else
392 {
393 $CACHE{$param} = $value;
394 }
396 SaveCache();
397 }
399 sub LoadCache
400 {
401 return if exists( $CACHE{'_cache_loaded_'} );
403 if ( -f $CACHEFILENAME )
404 {
405 my( $fileHandle ) = new IO::File;
407 if ( ! $fileHandle->open( "< ${CACHEFILENAME}" ) )
408 {
409 print STDERR "NPTest::LoadCache() : Problem opening ${CACHEFILENAME} : $!\n";
410 return;
411 }
413 my( $fileContents ) = join( "\n", <$fileHandle> );
415 $fileHandle->close();
417 my( $contentsRef ) = eval $fileContents;
418 %CACHE = %{$contentsRef};
420 }
422 $CACHE{'_cache_loaded_'} = 1;
423 }
426 sub SaveCache
427 {
428 delete $CACHE{'_cache_loaded_'};
430 my( $fileHandle ) = new IO::File;
432 if ( ! $fileHandle->open( "> ${CACHEFILENAME}" ) )
433 {
434 print STDERR "NPTest::LoadCache() : Problem saving ${CACHEFILENAME} : $!\n";
435 return;
436 }
438 my( $dataDumper ) = new Data::Dumper( [ \%CACHE ] );
440 $dataDumper->Terse(1);
442 print $fileHandle $dataDumper->Dump();
444 $fileHandle->close();
446 $CACHE{'_cache_loaded_'} = 1;
447 }
449 #
450 # (Questionable) Public Cache Management Functions
451 #
453 sub SetCacheFilename
454 {
455 my( $filename ) = @_;
457 # Unfortunately we can not validate the filename
458 # in any meaningful way, as it may not yet exist
459 $CACHEFILENAME = $filename;
460 }
463 #
464 # Test Harness Wrapper Functions
465 #
467 sub DetermineTestHarnessDirectory
468 {
469 my( $userSupplied ) = @_;
471 # User Supplied
472 if ( defined( $userSupplied ) && $userSupplied )
473 {
474 if ( -d $userSupplied )
475 {
476 return $userSupplied;
477 }
478 else
479 {
480 return undef; # userSupplied is invalid -> FAIL
481 }
482 }
484 # Simple Case : "t" is a subdirectory of the current directory
485 if ( -d "./t" )
486 {
487 return "./t";
488 }
490 # To be honest I don't understand which case satisfies the
491 # original code in test.pl : when $tstdir == `pwd` w.r.t.
492 # $tstdir =~ s|^(.*)/([^/]+)/?$|$1/$2|; and if (-d "../../$2/t")
493 # Assuming pwd is "/a/b/c/d/e" then we are testing for "/a/b/c/e/t"
494 # if I understand the code correctly (a big assumption)
496 # Simple Case : the current directory is "t"
497 my $pwd = cwd();
499 if ( $pwd =~ m|/t$| )
500 {
501 return $pwd;
503 # The alternate that might work better is
504 # chdir( ".." );
505 # return "./t";
506 # As the current test harnesses assume the application
507 # to be tested is in the current directory (ie "./check_disk ....")
508 }
510 return undef;
511 }
513 sub TestsFrom
514 {
515 my( $directory, $excludeIfAppMissing ) = @_;
517 $excludeIfAppMissing = 0 unless defined( $excludeIfAppMissing );
519 if ( ! opendir( DIR, $directory ) )
520 {
521 print STDERR "NPTest::TestsFrom() - Failed to open ${directory} : $!\n";
522 return ();
523 }
525 my( @tests ) = ();
527 my $filename;
528 my $application;
530 while ( $filename = readdir( DIR ) )
531 {
532 if ( $filename =~ m/\.t$/ )
533 {
534 if ( $excludeIfAppMissing )
535 {
536 $application = basename( $filename, ".t" );
537 if ( ! -e $application )
538 {
539 print STDERR "No application (${application}) found for test harness (${filename})\n";
540 next;
541 }
542 }
543 push @tests, "${directory}/${filename}";
544 }
545 }
547 closedir( DIR );
549 return @tests;
550 }
552 # All the new object oriented stuff below
554 sub new {
555 my $type = shift;
556 my $self = {};
557 return bless $self, $type;
558 }
560 # Accessors
561 sub return_code {
562 my $self = shift;
563 if (@_) {
564 return $self->{return_code} = shift;
565 } else {
566 return $self->{return_code};
567 }
568 }
569 sub output {
570 my $self = shift;
571 if (@_) {
572 return $self->{output} = shift;
573 } else {
574 return $self->{output};
575 }
576 }
578 sub testCmd {
579 my $class = shift;
580 my $command = shift or die "No command passed to testCmd";
581 my $object = $class->new;
583 my $output = `$command`;
584 chomp $output;
586 $object->output($output);
587 $object->return_code($? >> 8);
589 if ($ENV{'NPTEST_DEBUG'}) {
590 my ($pkg, $file, $line) = caller(0);
591 print "testCmd: Called from line $line in $file", $/;
592 print "Testing: $command", $/;
593 print "Output: ", $object->output, $/;
594 print "Return code: ", $object->return_code, $/;
595 }
597 return $object;
598 }
600 1;
601 #
602 # End of File
603 #