Merge pull request #44 from athal7/add-result-count-check

Add check for alerting on query result count

CHANGELOG.md

@@ -4,6 +4,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 This CHANGELOG follows the format listed at [Keep A Changelog](http://keepachangelog.com/)
 
 ## [Unreleased]
+- Added check-mysql-query-result-count.rb script
 
 ## [1.1.0] - 2017-01-15
 ### Added

README.md

@@ -16,6 +16,7 @@
  * bin/check-mysql-disk.rb
  * bin/check-mysql-innodb-lock.rb
  * bin/check-mysql-threads.rb
+ * bin/check-mysql-query-result-count.rb
  * bin/metrics-mysql-graphite.rb
  * bin/metrics-mysql-processes.rb
  * bin/metrics-mysql-raw.rb
@@ -45,6 +46,11 @@
 /opt/sensu/embedded/bin$ /opt/sensu/embedded/bin/ruby check-mysql-connections.rb --host=localhost --port=3306 --user=collectd --pass=tflypass --socket=/data/mysql.sock
 ```
 
+**check-mysql-query-result-count** example
+```bash
+/opt/sensu/embedded/bin$ /opt/sensu/embedded/bin/ruby check-mysql-query-result-count.rb --host=localhost --port=3306 --user=collectd --pass=tflypass --socket=/data/mysql.sock --warning 1 --critical 10 --query 'SELECT DISTINCT(t.id) FROM table t where t.failed = true'
+```
+
 ## Installation
 
 [Installation and Setup](http://sensu-plugins.io/docs/installation_instructions.html)
@@ -53,7 +59,7 @@
 The ruby executables are install in path similar to `/opt/sensu/embedded/lib/ruby/gems/2.0.0/gems/sensu-plugins-mysql-0.0.4/bin`
 
 ## Troubleshooting
-When used in `chef`, if the dependencies are missing, an error may abort the chef-client run: 
+When used in `chef`, if the dependencies are missing, an error may abort the chef-client run:
 ```bash
 *** extconf.rb failed ***
 Could not create Makefile due to some reason, probably lack of

bin/check-mysql-query-result-count.rb

@@ -0,0 +1,102 @@
+#!/usr/bin/env ruby
+#
+# MySQL Query Result Count Check
+#
+# Checks the length of a result set from a MySQL query.
+#
+# Copyright 2017 Andrew Thal <[email protected]>
+#
+# Released under the same terms as Sensu (the MIT license); see LICENSE
+# for details.
+
+require 'sensu-plugin/check/cli'
+require 'mysql'
+require 'inifile'
+
+class MysqlQueryCountCheck < Sensu::Plugin::Check::CLI
+  option :host,
+         short: '-h HOST',
+         long: '--host HOST',
+         description: 'MySQL Host to connect to',
+         required: true
+
+  option :port,
+         short: '-P PORT',
+         long: '--port PORT',
+         description: 'MySQL Port to connect to',
+         proc: proc(&:to_i),
+         default: 3306
+
+  option :username,
+         short: '-u USERNAME',
+         long: '--user USERNAME',
+         description: 'MySQL Username'
+
+  option :password,
+         short: '-p PASSWORD',
+         long: '--pass PASSWORD',
+         description: 'MySQL password',
+         default: ''
+
+  option :ini,
+         short: '-i',
+         long: '--ini VALUE',
+         description: 'My.cnf ini file'
+
+  option :socket,
+         short: '-S SOCKET',
+         long: '--socket SOCKET',
+         description: 'MySQL Unix socket to connect to'
+
+  option :warn,
+         short: '-w COUNT',
+         long: '--warning COUNT',
+         description: 'COUNT warning threshold for number of items returned by the query',
+         proc: proc(&:to_i),
+         required: true
+
+  option :crit,
+         short: '-c COUNT',
+         long: '--critical COUNT',
+         description: 'COUNT critical threshold for number of items returned by the query',
+         proc: proc(&:to_i),
+         required: true
+
+  option :query,
+         short: '-q QUERY',
+         long: '--query QUERY',
+         description: 'Query to execute',
+         required: true
+
+  def run
+    if config[:ini]
+      ini = IniFile.load(config[:ini])
+      section = ini['client']
+      db_user = section['user']
+      db_pass = section['password']
+    else
+      db_user = config[:user]
+      db_pass = config[:password]
+    end
+    db = Mysql.real_connect(config[:hostname], db_user, db_pass, config[:database], config[:port].to_i, config[:socket])
+    length = db.query(config[:query]).count
+
+    if length >= config[:crit]
+      critical "Result count is above the CRITICAL limit: #{length} length / #{config[:crit]} limit"
+    elsif length >= config[:warn]
+      warning "Result count is above the WARNING limit: #{length} length / #{config[:warn]} limit"
+    else
+      ok 'Result count length is below thresholds'
+    end
+
+  rescue Mysql::Error => e
+    errstr = "Error code: #{e.errno} Error message: #{e.error}"
+    critical "#{errstr} SQLSTATE: #{e.sqlstate}" if e.respond_to?('sqlstate')
+
+  rescue => e
+    critical e
+
+  ensure
+    db.close if db
+  end
+end