Merge pull request #9 from Altiscale/karthik_check_zookeeper_mode

check zookeeper mode

Author: eheydrick

CHANGELOG.md

@@ -5,6 +5,9 @@ This CHANGELOG follows the format listed at [Keep A Changelog](http://keepachang
 
 ## [Unreleased]
 
+## [1.1.0]
+- check-zookeeper-mode
+
 ## [1.0.0] - 2017-03-21
 ### Added
 - check-zookeeper-reqs (@grem11n)

README.md

@@ -15,6 +15,7 @@
 * check-zookeeper-latency.rb - Check average latency on Zookeeper node
 * check-zookeeper-reqs.rb - Check if Zookeeper node has reliable number of outstanding requests
 * check-zookeeper-ruok.rb - Check if Zookeeper node responds to 'ruok' query succesfully
+* check-zookeeper-mode.rb - Check if Zookeeper node is in standalone or cluster(leader or follower) mode
 * metrics-zookeeper.rb - Gather metrics from Zookeeper
 
 ## Usage

bin/check-zookeeper-mode.rb

@@ -0,0 +1,84 @@
+#!/usr/bin/env ruby
+#  encoding: UTF-8
+#
+#  check-zookeeper-mode
+#
+# DESCRIPTION:
+#   Check if Zookeeper node is in expected mode.
+#
+#   'mode' is ZooKeeper's mode which can be standalone or in a cluster.
+#   In cluster mode a Zookeeper node can be either leader or follower.
+#   We use stat command to get the mode and check if zookeeper node is a
+#   standalone or leader or follower.
+#
+# PLATFORMS:
+#   All
+#
+# DEPENDENCIES:
+#   gem: sensu-plugin
+#
+# USAGE:
+#  Check if a node has Zookeeper running and responds with imok.
+#  ./check-zookeeeper-mode.rb -m 'leader follower'
+#  ./check-zookeeeper-mode.rb -s localhost -p 2181 -m 'leader follower'
+#  ./check-zookeeeper-mode.rb --server localhost --port 2181 --mode 'leader follower'
+#
+
+require 'sensu-plugin/check/cli'
+require 'socket'
+
+class CheckZookeeperMode < Sensu::Plugin::Check::CLI
+  option :server,
+         description: 'Zookeeper hostname to connect to.',
+         short: '-s HOSTNAME',
+         long: '--server HOSTNAME',
+         default: 'localhost'
+
+  option :port,
+         description: 'Zookeeper port to connect to.',
+         short: '-p PORT',
+         long: '--port PORT',
+         default: 2181
+
+  option :timeout,
+         description: 'How long to wait for a reply in seconds.',
+         short: '-t SECS',
+         long: '--timeout SECS',
+         proc: proc(&:to_i),
+         default: 5
+
+  option :mode,
+         description: 'Space separated expected modes.',
+         short: '-m MODE',
+         long: '--mode MODE',
+         required: true
+
+  def zk_command(four_letter_word)
+    Socket.tcp(config[:server], config[:port]) do |sock|
+      sock.print "#{four_letter_word}\r\n"
+      sock.close_write
+      sock.read
+    end
+  end
+
+  def run
+    response = zk_command(:stat)
+    mode = get_mode(response)
+    expected_modes = config[:mode].split
+    if expected_modes.include?(mode)
+      ok(mode)
+    else
+      critical("Zookeeper mode is #{mode} and it does not match #{expected_modes.join(', ')}")
+    end
+  end
+
+  private
+
+  def get_mode(response)
+    response.each_line do |line|
+      line = line.chomp
+      k, v = line.split(': ')
+      return v if k == 'Mode'
+    end
+  end
+end

lib/sensu-plugins-zookeeper/version.rb

@@ -1,7 +1,7 @@
 module SensuPluginsZookeeper
   module Version
     MAJOR = 1
-    MINOR = 0
+    MINOR = 1
     PATCH = 0
 
     VER_STRING = [MAJOR, MINOR, PATCH].compact.join('.')