[monitoring-plugins] tests: make check_snmp test more reliable

[Sven Nierlein]

 Module: monitoring-plugins
 Branch: master
 Commit: 22f47fc0c51266bd25491da30fd165a845a1391b
 Author: Sven Nierlein <sven at nierlein.de>
   Date: Mon Jan 21 17:41:02 2019 +0100
    URL: https://www.monitoring-plugins.org/repositories/monitoring-plugins/commit/?id=22f47fc

tests: make check_snmp test more reliable

The check_snmp rate tests depend on the exact amount of time spend between the
plugin runs and will fail on busy machines, ex. the ci servers. Using faketime
mitigates this issue and also removes all the sleeps.

Signed-off-by: Sven Nierlein <sven at nierlein.de>

---

 plugins/tests/check_snmp.t | 110 ++++++++++++++++++++++++---------------------
 1 file changed, 58 insertions(+), 52 deletions(-)

diff --git a/plugins/tests/check_snmp.t b/plugins/tests/check_snmp.t
index 73a68b2..85d6bf5 100755
--- a/plugins/tests/check_snmp.t
+++ b/plugins/tests/check_snmp.t
@@ -7,6 +7,7 @@ use strict;
 use Test::More;
 use NPTest;
 use FindBin qw($Bin);
+use POSIX qw/strftime/;
 
 my $tests = 67;
 # Check that all dependent modules are available
@@ -37,6 +38,7 @@ if ($@) {
 
 my $port_snmp = 16100 + int(rand(100));
 
+my $faketime = -x '/usr/bin/faketime' ? 1 : 0;
 
 # Start up server
 my @pids;
@@ -118,77 +120,81 @@ like($res->output, '/'.quotemeta('SNMP OK - And now have fun with with this: \"C
 "And now have fun with with this: \"C:\\\\\"
 because we\'re not done yet!"').'/m', "Attempt to confuse parser No.3");
 
-system("rm -f ".$ENV{'MP_STATE_PATH'}."/check_snmp/*");
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -w 600" );
-is($res->return_code, 0, "Returns OK");
-is($res->output, "No previous data to calculate rate - assume okay");
+system("rm -f ".$ENV{'MP_STATE_PATH'}."/*/check_snmp/*");
 
-# Need to sleep, otherwise duration=0
-sleep 1;
+# run rate checks with faketime. rate checks depend on the exact amount of time spend between the
+# plugin runs which may fail on busy machines.
+# using faketime removes this race condition and also saves all the sleeps in between.
+SKIP: {
+    skip "No faketime binary found", 28 if !$faketime;
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -w 600" );
-is($res->return_code, 1, "WARNING - due to going above rate calculation" );
-is($res->output, "SNMP RATE WARNING - *666* | iso.3.6.1.4.1.8072.3.2.67.10=666;600 ");
+    my $ts = time();
+    $res = NPTest->testCmd("LC_TIME=C TZ=UTC faketime -f '".strftime("%Y-%m-%d %H:%M:%S", localtime($ts))."' ./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -w 600" );
+    is($res->return_code, 0, "Returns OK");
+    is($res->output, "No previous data to calculate rate - assume okay");
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -w 600" );
-is($res->return_code, 3, "UNKNOWN - basically the divide by zero error" );
-is($res->output, "Time duration between plugin calls is invalid");
+    # test rate 1 second later
+    $res = NPTest->testCmd("LC_TIME=C TZ=UTC faketime -f '".strftime("%Y-%m-%d %H:%M:%S", localtime($ts+1))."' ./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -w 600" );
+    is($res->return_code, 1, "WARNING - due to going above rate calculation" );
+    is($res->output, "SNMP RATE WARNING - *666* | iso.3.6.1.4.1.8072.3.2.67.10=666;600 ");
 
+    # test rate with same time
+    $res = NPTest->testCmd("LC_TIME=C TZ=UTC faketime -f '".strftime("%Y-%m-%d %H:%M:%S", localtime($ts+1))."' ./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -w 600" );
+    is($res->return_code, 3, "UNKNOWN - basically the divide by zero error" );
+    is($res->output, "Time duration between plugin calls is invalid");
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets" );
-is($res->return_code, 0, "OK for first call" );
-is($res->output, "No previous data to calculate rate - assume okay" );
 
-# Need to sleep, otherwise duration=0
-sleep 1;
+    $res = NPTest->testCmd("LC_TIME=C TZ=UTC faketime -f '".strftime("%Y-%m-%d %H:%M:%S", localtime($ts))."' ./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets" );
+    is($res->return_code, 0, "OK for first call" );
+    is($res->output, "No previous data to calculate rate - assume okay" );
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP RATE OK - inoctets 666 | inoctets=666 ", "Check label");
+    # test rate 1 second later
+    $res = NPTest->testCmd("LC_TIME=C TZ=UTC faketime -f '".strftime("%Y-%m-%d %H:%M:%S", localtime($ts+1))."' ./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP RATE OK - inoctets 666 | inoctets=666 ", "Check label");
 
-sleep 2;
+    # test rate 3 seconds later
+    $res = NPTest->testCmd("LC_TIME=C TZ=UTC faketime -f '".strftime("%Y-%m-%d %H:%M:%S", localtime($ts+3))."' ./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP RATE OK - inoctets 333 | inoctets=333 ", "Check rate decreases due to longer interval");
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP RATE OK - inoctets 333 | inoctets=333 ", "Check rate decreases due to longer interval");
 
+    # label performance data check
+    $res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l test" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP OK - test 67996 | test=67996c ", "Check label");
 
-# label performance data check
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l test" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP OK - test 67996 | test=67996c ", "Check label");
+    $res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l \"test'test\"" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP OK - test'test 68662 | \"test'test\"=68662c ", "Check label");
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l \"test'test\"" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP OK - test'test 68662 | \"test'test\"=68662c ", "Check label");
+    $res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l 'test\"test'" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP OK - test\"test 69328 | 'test\"test'=69328c ", "Check label");
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l 'test\"test'" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP OK - test\"test 69328 | 'test\"test'=69328c ", "Check label");
+    $res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l test -O" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP OK - test 69994 | iso.3.6.1.4.1.8072.3.2.67.10=69994c ", "Check label");
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l test -O" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP OK - test 69994 | iso.3.6.1.4.1.8072.3.2.67.10=69994c ", "Check label");
+    $res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP OK - 70660 | iso.3.6.1.4.1.8072.3.2.67.10=70660c ", "Check label");
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP OK - 70660 | iso.3.6.1.4.1.8072.3.2.67.10=70660c ", "Check label");
+    $res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l 'test test'" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP OK - test test 71326 | 'test test'=71326c ", "Check label");
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 -l 'test test'" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP OK - test test 71326 | 'test test'=71326c ", "Check label");
 
+    $res = NPTest->testCmd("LC_TIME=C TZ=UTC faketime -f '".strftime("%Y-%m-%d %H:%M:%S", localtime($ts))."' ./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets_per_minute --rate-multiplier=60" );
+    is($res->return_code, 0, "OK for first call" );
+    is($res->output, "No previous data to calculate rate - assume okay" );
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets_per_minute --rate-multiplier=60" );
-is($res->return_code, 0, "OK for first call" );
-is($res->output, "No previous data to calculate rate - assume okay" );
-
-# Need to sleep, otherwise duration=0
-sleep 1;
+    # test 1 second later
+    $res = NPTest->testCmd("LC_TIME=C TZ=UTC faketime -f '".strftime("%Y-%m-%d %H:%M:%S", localtime($ts+1))."' ./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets_per_minute --rate-multiplier=60" );
+    is($res->return_code, 0, "OK as no thresholds" );
+    is($res->output, "SNMP RATE OK - inoctets_per_minute 39960 | inoctets_per_minute=39960 ", "Checking multiplier");
+};
 
-$res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.10 --rate -l inoctets_per_minute --rate-multiplier=60" );
-is($res->return_code, 0, "OK as no thresholds" );
-is($res->output, "SNMP RATE OK - inoctets_per_minute 39960 | inoctets_per_minute=39960 ", "Checking multiplier");
 
 
 $res = NPTest->testCmd( "./check_snmp -H 127.0.0.1 -C public -p $port_snmp -o .1.3.6.1.4.1.8072.3.2.67.11 -s '\"stringtests\"'" );