From 2a6d610b7abc397b44d506a8f17bba78b0a9efd5 Mon Sep 17 00:00:00 2001
From: Belen Bustamante <rooneyshuman@gmail.com>
Date: Fri, 23 Oct 2020 09:50:31 -0700
Subject: [PATCH] Rubocop fix

---
 lib/vmpooler.rb                      |  20 +++---
 lib/vmpooler/api/dashboard.rb        |  36 +++++-----
 lib/vmpooler/api/helpers.rb          |  24 +++----
 lib/vmpooler/api/v1.rb               |  80 ++++++++++-----------
 lib/vmpooler/metrics/dummy_statsd.rb |   3 -
 lib/vmpooler/metrics/graphite.rb     |   2 +
 lib/vmpooler/metrics/promstats.rb    |   2 +
 lib/vmpooler/metrics/statsd.rb       |   8 ++-
 lib/vmpooler/pool_manager.rb         | 103 +++++++++++++--------------
 lib/vmpooler/providers/dummy.rb      |  58 ++++++---------
 lib/vmpooler/providers/vsphere.rb    |  45 +++++-------
 spec/rbvmomi_helper.rb               |   2 +-
 spec/unit/pool_manager_spec.rb       |  14 ++--
 spec/unit/providers/vsphere_spec.rb  |   8 +--
 vmpooler.gemspec                     |   2 +-
 15 files changed, 182 insertions(+), 225 deletions(-)

diff --git a/lib/vmpooler.rb b/lib/vmpooler.rb
index bbc68f8..cee8db8 100644
--- a/lib/vmpooler.rb
+++ b/lib/vmpooler.rb
@@ -53,17 +53,13 @@ module Vmpooler
 
     # Bail out if someone attempts to start vmpooler with dummy authentication
     # without enbaling debug mode.
-    if parsed_config.key? :auth
-      if parsed_config[:auth]['provider'] == 'dummy'
-        unless ENV['VMPOOLER_DEBUG']
-          warning = [
-            'Dummy authentication should not be used outside of debug mode',
-            'please set environment variable VMPOOLER_DEBUG to \'true\' if you want to use dummy authentication'
-          ]
+    if parsed_config.key?(:auth) && parsed_config[:auth]['provider'] == 'dummy' && !ENV['VMPOOLER_DEBUG']
+      warning = [
+        'Dummy authentication should not be used outside of debug mode',
+        'please set environment variable VMPOOLER_DEBUG to \'true\' if you want to use dummy authentication'
+      ]
 
-          raise warning.join(";\s")
-        end
-      end
+      raise warning.join(";\s")
     end
 
     # Set some configuration defaults
@@ -140,14 +136,14 @@ module Vmpooler
       parsed_config[:pool_names] << pool['name']
       pool['ready_ttl'] ||= parsed_config[:config]['ready_ttl']
       if pool['alias']
-        if pool['alias'].is_a?(Array)
+        if pool['alias'].instance_of?(Array)
           pool['alias'].each do |pool_alias|
             parsed_config[:alias] ||= {}
             parsed_config[:alias][pool_alias] = [pool['name']] unless parsed_config[:alias].key? pool_alias
             parsed_config[:alias][pool_alias] << pool['name'] unless parsed_config[:alias][pool_alias].include? pool['name']
             parsed_config[:pool_names] << pool_alias
           end
-        elsif pool['alias'].is_a?(String)
+        elsif pool['alias'].instance_of?(String)
           parsed_config[:alias][pool['alias']] = pool['name']
           parsed_config[:pool_names] << pool['alias']
         end
diff --git a/lib/vmpooler/api/dashboard.rb b/lib/vmpooler/api/dashboard.rb
index 4c56798..f5e65cf 100644
--- a/lib/vmpooler/api/dashboard.rb
+++ b/lib/vmpooler/api/dashboard.rb
@@ -128,34 +128,32 @@ module Vmpooler
 
         pools.each do |pool|
           running = running_hash[pool['name']]
-          pool['major'] = Regexp.last_match[1] if pool['name'] =~ /^(\w+)\-/
+          pool['major'] = Regexp.last_match[1] if pool['name'] =~ /^(\w+)-/
           result[pool['major']] ||= {}
           result[pool['major']]['running'] = result[pool['major']]['running'].to_i + running.to_i
         end
 
-        if params[:history]
-          if graph_url
-            begin
-              buffer = URI.parse(graph_link('.running.*&from=-1hour&format=json')).read
-              JSON.parse(buffer).each do |pool|
-                if pool['target'] =~ /.*\.(.*)$/
-                  pool['name'] = Regexp.last_match[1]
-                  pool['major'] = Regexp.last_match[1] if pool['name'] =~ /^(\w+)\-/
-                  result[pool['major']]['history'] ||= []
+        if params[:history] && graph_url
+          begin
+            buffer = URI.parse(graph_link('.running.*&from=-1hour&format=json')).read
+            JSON.parse(buffer).each do |pool|
+              if pool['target'] =~ /.*\.(.*)$/
+                pool['name'] = Regexp.last_match[1]
+                pool['major'] = Regexp.last_match[1] if pool['name'] =~ /^(\w+)-/
+                result[pool['major']]['history'] ||= []
 
-                  for i in 0..pool['datapoints'].length
-                    if pool['datapoints'][i] && pool['datapoints'][i][0]
-                      pool['last'] = pool['datapoints'][i][0]
-                      result[pool['major']]['history'][i] ||= 0
-                      result[pool['major']]['history'][i] = result[pool['major']]['history'][i].to_i + pool['datapoints'][i][0].to_i
-                    else
-                      result[pool['major']]['history'][i] = result[pool['major']]['history'][i].to_i + pool['last'].to_i
-                    end
+                for i in 0..pool['datapoints'].length
+                  if pool['datapoints'][i] && pool['datapoints'][i][0]
+                    pool['last'] = pool['datapoints'][i][0]
+                    result[pool['major']]['history'][i] ||= 0
+                    result[pool['major']]['history'][i] = result[pool['major']]['history'][i].to_i + pool['datapoints'][i][0].to_i
+                  else
+                    result[pool['major']]['history'][i] = result[pool['major']]['history'][i].to_i + pool['last'].to_i
                   end
                 end
               end
-            rescue StandardError
             end
+          rescue StandardError
           end
         end
         JSON.pretty_generate(result)
diff --git a/lib/vmpooler/api/helpers.rb b/lib/vmpooler/api/helpers.rb
index 1fd4325..0f23842 100644
--- a/lib/vmpooler/api/helpers.rb
+++ b/lib/vmpooler/api/helpers.rb
@@ -13,12 +13,12 @@ module Vmpooler
       def valid_token?(backend)
         return false unless has_token?
 
-        backend.exists?('vmpooler__token__' + request.env['HTTP_X_AUTH_TOKEN']) ? true : false
+        backend.exists?("vmpooler__token__#{request.env['HTTP_X_AUTH_TOKEN']}") ? true : false
       end
 
       def validate_token(backend)
         if valid_token?(backend)
-          backend.hset('vmpooler__token__' + request.env['HTTP_X_AUTH_TOKEN'], 'last', Time.now)
+          backend.hset("vmpooler__token__#{request.env['HTTP_X_AUTH_TOKEN']}last#{Time.now}")
 
           return true
         end
@@ -117,8 +117,8 @@ module Vmpooler
         tags.each_pair do |tag, value|
           next if value.nil? or value.empty?
 
-          backend.hset('vmpooler__vm__' + hostname, 'tag:' + tag, value)
-          backend.hset('vmpooler__tag__' + Date.today.to_s, hostname + ':' + tag, value)
+          backend.hset("vmpooler__vm__#{hostname}", "tag:#{tag}", value)
+          backend.hset("vmpooler__tag__#{Date.today}", "#{hostname}:#{tag}", value)
         end
       end
 
@@ -145,7 +145,7 @@ module Vmpooler
 
       def hostname_shorten(hostname, domain=nil)
         if domain && hostname =~ /^[\w-]+\.#{domain}$/
-          hostname = hostname[/[^\.]+/]
+          hostname = hostname[/[^.]+/]
         end
 
         hostname
@@ -251,17 +251,15 @@ module Vmpooler
 
         tags = {}
 
-        backend.hgetall('vmpooler__tag__' + date_str).each do |key, value|
+        backend.hgetall("vmpooler__tag__#{date_str}").each do |key, value|
           hostname = 'unknown'
           tag = 'unknown'
 
-          if key =~ /\:/
+          if key =~ /:/
             hostname, tag = key.split(':', 2)
           end
 
-          if opts[:only]
-            next unless tag == opts[:only]
-          end
+          next if opts[:only] && tag != opts[:only]
 
           tags[tag] ||= {}
           tags[tag][value] ||= 0
@@ -319,7 +317,7 @@ module Vmpooler
             }
         }
 
-        task[:count][:total] = backend.hlen('vmpooler__' + task_str + '__' + date_str).to_i
+        task[:count][:total] = backend.hlen("vmpooler__#{task_str}__#{date_str}").to_i
 
         if task[:count][:total] > 0
           if opts[:bypool] == true
@@ -328,11 +326,11 @@ module Vmpooler
             task[:count][:pool]    = {}
             task[:duration][:pool] = {}
 
-            backend.hgetall('vmpooler__' + task_str + '__' + date_str).each do |key, value|
+            backend.hgetall("vmpooler__#{task_str}__#{date_str}").each do |key, value|
               pool     = 'unknown'
               hostname = 'unknown'
 
-              if key =~ /\:/
+              if key =~ /:/
                 pool, hostname = key.split(':')
               else
                 hostname = key
diff --git a/lib/vmpooler/api/v1.rb b/lib/vmpooler/api/v1.rb
index 066af86..1f4a23e 100644
--- a/lib/vmpooler/api/v1.rb
+++ b/lib/vmpooler/api/v1.rb
@@ -174,13 +174,13 @@ module Vmpooler
       if Vmpooler::API.settings.config[:auth] and has_token?
         validate_token(backend)
 
-        backend.hset('vmpooler__vm__' + vm, 'token:token', request.env['HTTP_X_AUTH_TOKEN'])
-        backend.hset('vmpooler__vm__' + vm, 'token:user',
-                     backend.hget('vmpooler__token__' + request.env['HTTP_X_AUTH_TOKEN'], 'user')
+        backend.hset("vmpooler__vm__#{vm}", 'token:token', request.env['HTTP_X_AUTH_TOKEN'])
+        backend.hset("vmpooler__vm__#{vm}", 'token:user',
+                     backend.hget("vmpooler__token__#{request.env['HTTP_X_AUTH_TOKEN']}", 'user')
         )
 
         if config['vm_lifetime_auth'].to_i > 0
-          backend.hset('vmpooler__vm__' + vm, 'lifetime', config['vm_lifetime_auth'].to_i)
+          backend.hset("vmpooler__vm__#{vm}", 'lifetime', config['vm_lifetime_auth'].to_i)
         end
       end
     end
@@ -205,11 +205,11 @@ module Vmpooler
           vmname, vmpool, vmtemplate = fetch_single_vm(requested)
           if !vmname
             failed = true
-            metrics.increment('checkout.empty.' + requested)
+            metrics.increment("checkout.empty.#{requested}")
             break
           else
             vms << [vmpool, vmname, vmtemplate]
-            metrics.increment('checkout.success.' + vmtemplate)
+            metrics.increment("checkout.success.#{vmtemplate}")
           end
         end
       end
@@ -337,7 +337,7 @@ module Vmpooler
       payload&.each do |poolname, count|
         next unless count.to_i > config['max_ondemand_instances_per_request']
 
-        metrics.increment('ondemandrequest_fail.toomanyrequests.' + poolname)
+        metrics.increment("ondemandrequest_fail.toomanyrequests.#{poolname}")
         return true
       end
       false
@@ -380,7 +380,7 @@ module Vmpooler
       if Vmpooler::API.settings.config[:auth] and has_token?
         backend.hset("vmpooler__odrequest__#{request_id}", 'token:token', request.env['HTTP_X_AUTH_TOKEN'])
         backend.hset("vmpooler__odrequest__#{request_id}", 'token:user',
-                     backend.hget('vmpooler__token__' + request.env['HTTP_X_AUTH_TOKEN'], 'user'))
+                     backend.hget("vmpooler__token__#{request.env['HTTP_X_AUTH_TOKEN']}", 'user'))
       end
 
       result['domain'] = config['domain'] if config['domain']
@@ -542,9 +542,9 @@ module Vmpooler
           if subpool.include?(p['name'])
             true
           elsif !p['alias'].nil?
-            if p['alias'].is_a?(Array)
+            if p['alias'].instance_of?(Array)
               (p['alias'] & subpool).any?
-            elsif p['alias'].is_a?(String)
+            elsif p['alias'].instance_of?(String)
               subpool.include?(p['alias'])
             end
           end
@@ -727,14 +727,14 @@ module Vmpooler
       result = { 'ok' => false }
 
       if Vmpooler::API.settings.config[:auth]
-        token = backend.hgetall('vmpooler__token__' + params[:token])
+        token = backend.hgetall("vmpooler__token__#{params[:token]}")
 
         if not token.nil? and not token.empty?
           status 200
 
           pools.each do |pool|
-            backend.smembers('vmpooler__running__' + pool['name']).each do |vm|
-              if backend.hget('vmpooler__vm__' + vm, 'token:token') == params[:token]
+            backend.smembers("vmpooler__running__#{pool['name']}").each do |vm|
+              if backend.hget("vmpooler__vm__#{vm}", 'token:token') == params[:token]
                 token['vms'] ||= {}
                 token['vms']['running'] ||= []
                 token['vms']['running'].push(vm)
@@ -760,7 +760,7 @@ module Vmpooler
 
         need_auth!
 
-        if backend.del('vmpooler__token__' + params[:token]).to_i > 0
+        if backend.del("vmpooler__token__#{params[:token]}").to_i > 0
           status 200
           result['ok'] = true
         end
@@ -783,8 +783,8 @@ module Vmpooler
         o = [('a'..'z'), ('0'..'9')].map(&:to_a).flatten
         result['token'] = o[rand(25)] + (0...31).map { o[rand(o.length)] }.join
 
-        backend.hset('vmpooler__token__' + result['token'], 'user', @auth.username)
-        backend.hset('vmpooler__token__' + result['token'], 'created', Time.now)
+        backend.hset("vmpooler__token__#{result['token']}", 'user', @auth.username)
+        backend.hset("vmpooler__token__#{result['token']}", 'created', Time.now)
 
         status 200
         result['ok'] = true
@@ -823,7 +823,7 @@ module Vmpooler
           else
             result[:bad_templates] = invalid
             invalid.each do |bad_template|
-              metrics.increment('ondemandrequest_fail.invalid.' + bad_template)
+              metrics.increment("ondemandrequest_fail.invalid.#{bad_template}")
             end
             status 404
           end
@@ -858,7 +858,7 @@ module Vmpooler
         else
           result[:bad_templates] = invalid
           invalid.each do |bad_template|
-            metrics.increment('ondemandrequest_fail.invalid.' + bad_template)
+            metrics.increment("ondemandrequest_fail.invalid.#{bad_template}")
           end
           status 404
         end
@@ -904,7 +904,7 @@ module Vmpooler
           result = atomically_allocate_vms(payload)
         else
           invalid.each do |bad_template|
-            metrics.increment('checkout.invalid.' + bad_template)
+            metrics.increment("checkout.invalid.#{bad_template}")
           end
           status 404
         end
@@ -980,7 +980,8 @@ module Vmpooler
       result['ok'] = true
       status 202
 
-      if request_hash['status'] == 'ready'
+      case request_hash['status']
+      when 'ready'
         result['ready'] = true
         Parsing.get_platform_pool_count(request_hash['requested']) do |platform_alias, pool, _count|
           instances = backend.smembers("vmpooler__#{request_id}__#{platform_alias}__#{pool}")
@@ -993,10 +994,10 @@ module Vmpooler
         end
         result['domain'] = config['domain'] if config['domain']
         status 200
-      elsif request_hash['status'] == 'failed'
+      when 'failed'
         result['message'] = "The request failed to provision instances within the configured ondemand_request_ttl '#{config['ondemand_request_ttl']}'"
         status 200
-      elsif request_hash['status'] == 'deleted'
+      when 'deleted'
         result['message'] = 'The request has been deleted'
         status 200
       else
@@ -1059,7 +1060,7 @@ module Vmpooler
           result = atomically_allocate_vms(payload)
         else
           invalid.each do |bad_template|
-            metrics.increment('checkout.invalid.' + bad_template)
+            metrics.increment("checkout.invalid.#{bad_template}")
           end
           status 404
         end
@@ -1082,7 +1083,7 @@ module Vmpooler
 
       params[:hostname] = hostname_shorten(params[:hostname], config['domain'])
 
-      rdata = backend.hgetall('vmpooler__vm__' + params[:hostname])
+      rdata = backend.hgetall("vmpooler__vm__#{params[:hostname]}")
       unless rdata.empty?
         status 200
         result['ok'] = true
@@ -1155,12 +1156,12 @@ module Vmpooler
 
       params[:hostname] = hostname_shorten(params[:hostname], config['domain'])
 
-      rdata = backend.hgetall('vmpooler__vm__' + params[:hostname])
+      rdata = backend.hgetall("vmpooler__vm__#{params[:hostname]}")
       unless rdata.empty?
         need_token! if rdata['token:token']
 
-        if backend.srem('vmpooler__running__' + rdata['template'], params[:hostname])
-          backend.sadd('vmpooler__completed__' + rdata['template'], params[:hostname])
+        if backend.srem("vmpooler__running__#{rdata['template']}", params[:hostname])
+          backend.sadd("vmpooler__completed__#{rdata['template']}", params[:hostname])
 
           status 200
           result['ok'] = true
@@ -1184,7 +1185,7 @@ module Vmpooler
 
       params[:hostname] = hostname_shorten(params[:hostname], config['domain'])
 
-      if backend.exists?('vmpooler__vm__' + params[:hostname])
+      if backend.exists?("vmpooler__vm__#{params[:hostname]}")
         begin
           jdata = JSON.parse(request.body.read)
         rescue StandardError
@@ -1212,13 +1213,8 @@ module Vmpooler
               end
 
             when 'tags'
-              unless arg.is_a?(Hash)
-                failure.push("You provided tags (#{arg}) as something other than a hash.")
-              end
-
-              if config['allowed_tags']
-                failure.push("You provided unsuppored tags (#{arg}).") if not (arg.keys - config['allowed_tags']).empty?
-              end
+              failure.push("You provided tags (#{arg}) as something other than a hash.") unless arg.is_a?(Hash)
+              failure.push("You provided unsuppored tags (#{arg}).") if config['allowed_tags'] && !(arg.keys - config['allowed_tags']).empty?
             else
               failure.push("Unknown argument #{arg}.")
           end
@@ -1235,7 +1231,7 @@ module Vmpooler
 
                 arg = arg.to_i
 
-                backend.hset('vmpooler__vm__' + params[:hostname], param, arg)
+                backend.hset("vmpooler__vm__#{params[:hostname]}", param, arg)
               when 'tags'
                 filter_tags(arg)
                 export_tags(backend, params[:hostname], arg)
@@ -1261,11 +1257,11 @@ module Vmpooler
 
       params[:hostname] = hostname_shorten(params[:hostname], config['domain'])
 
-      if ((params[:size].to_i > 0 )and (backend.exists?('vmpooler__vm__' + params[:hostname])))
+      if ((params[:size].to_i > 0 )and (backend.exists?("vmpooler__vm__#{params[:hostname]}")))
         result[params[:hostname]] = {}
         result[params[:hostname]]['disk'] = "+#{params[:size]}gb"
 
-        backend.sadd('vmpooler__tasks__disk', params[:hostname] + ':' + params[:size])
+        backend.sadd('vmpooler__tasks__disk', "#{params[:hostname]}:#{params[:size]}")
 
         status 202
         result['ok'] = true
@@ -1285,13 +1281,13 @@ module Vmpooler
 
       params[:hostname] = hostname_shorten(params[:hostname], config['domain'])
 
-      if backend.exists?('vmpooler__vm__' + params[:hostname])
+      if backend.exists?("vmpooler__vm__#{params[:hostname]}")
         result[params[:hostname]] = {}
 
         o = [('a'..'z'), ('0'..'9')].map(&:to_a).flatten
         result[params[:hostname]]['snapshot'] = o[rand(25)] + (0...31).map { o[rand(o.length)] }.join
 
-        backend.sadd('vmpooler__tasks__snapshot', params[:hostname] + ':' + result[params[:hostname]]['snapshot'])
+        backend.sadd('vmpooler__tasks__snapshot', "#{params[:hostname]}:#{result[params[:hostname]]['snapshot']}")
 
         status 202
         result['ok'] = true
@@ -1311,8 +1307,8 @@ module Vmpooler
 
       params[:hostname] = hostname_shorten(params[:hostname], config['domain'])
 
-      unless backend.hget('vmpooler__vm__' + params[:hostname], 'snapshot:' + params[:snapshot]).to_i.zero?
-        backend.sadd('vmpooler__tasks__snapshot-revert', params[:hostname] + ':' + params[:snapshot])
+      unless backend.hget("vmpooler__vm__#{params[:hostname]}", "snapshot:#{params[:snapshot]}").to_i.zero?
+        backend.sadd('vmpooler__tasks__snapshot-revert', "#{params[:hostname]}:#{params[:snapshot]}")
 
         status 202
         result['ok'] = true
diff --git a/lib/vmpooler/metrics/dummy_statsd.rb b/lib/vmpooler/metrics/dummy_statsd.rb
index 96f2eaa..ad866b0 100644
--- a/lib/vmpooler/metrics/dummy_statsd.rb
+++ b/lib/vmpooler/metrics/dummy_statsd.rb
@@ -5,9 +5,6 @@ module Vmpooler
     class DummyStatsd < Metrics
       attr_reader :server, :port, :prefix
 
-      def initialize(*)
-      end
-
       def increment(*)
         true
       end
diff --git a/lib/vmpooler/metrics/graphite.rb b/lib/vmpooler/metrics/graphite.rb
index 128805d..88e66e3 100644
--- a/lib/vmpooler/metrics/graphite.rb
+++ b/lib/vmpooler/metrics/graphite.rb
@@ -7,6 +7,7 @@ module Vmpooler
     class Graphite < Metrics
       attr_reader :server, :port, :prefix
 
+      # rubocop:disable Lint/MissingSuper
       def initialize(logger, params = {})
         raise ArgumentError, "Graphite server is required. Config: #{params.inspect}" if params['server'].nil? || params['server'].empty?
 
@@ -15,6 +16,7 @@ module Vmpooler
         @prefix = params['prefix'] || 'vmpooler'
         @logger = logger
       end
+      # rubocop:enable Lint/MissingSuper
 
       def increment(label)
         log label, 1
diff --git a/lib/vmpooler/metrics/promstats.rb b/lib/vmpooler/metrics/promstats.rb
index bee432f..253879c 100644
--- a/lib/vmpooler/metrics/promstats.rb
+++ b/lib/vmpooler/metrics/promstats.rb
@@ -23,6 +23,7 @@ module Vmpooler
       @p_metrics = {}
       @torun = []
 
+      # rubocop:disable Lint/MissingSuper
       def initialize(logger, params = {})
         @prefix = params['prefix'] || 'vmpooler'
         @prometheus_prefix = params['prometheus_prefix'] || 'vmpooler'
@@ -32,6 +33,7 @@ module Vmpooler
         # Setup up prometheus registry and data structures
         @prometheus = Prometheus::Client.registry
       end
+# rubocop:enable Lint/MissingSuper
 
 =begin # rubocop:disable Style/BlockComments
       The Metrics table is used to register metrics and translate/interpret the incoming metrics.
diff --git a/lib/vmpooler/metrics/statsd.rb b/lib/vmpooler/metrics/statsd.rb
index 85b705d..b469c38 100644
--- a/lib/vmpooler/metrics/statsd.rb
+++ b/lib/vmpooler/metrics/statsd.rb
@@ -8,6 +8,7 @@ module Vmpooler
     class Statsd < Metrics
       attr_reader :server, :port, :prefix
 
+      # rubocop:disable Lint/MissingSuper
       def initialize(logger, params = {})
         raise ArgumentError, "Statsd server is required. Config: #{params.inspect}" if params['server'].nil? || params['server'].empty?
 
@@ -17,21 +18,22 @@ module Vmpooler
         @server = ::Statsd.new(host, @port)
         @logger = logger
       end
+      # rubocop:enable Lint/MissingSuper
 
       def increment(label)
-        server.increment(prefix + '.' + label)
+        server.increment("#{prefix}.#{label}")
       rescue StandardError => e
         @logger.log('s', "[!] Failure incrementing #{prefix}.#{label} on statsd server [#{server}:#{port}]: #{e}")
       end
 
       def gauge(label, value)
-        server.gauge(prefix + '.' + label, value)
+        server.gauge("#{prefix}.#{label}", value)
       rescue StandardError => e
         @logger.log('s', "[!] Failure updating gauge #{prefix}.#{label} on statsd server [#{server}:#{port}]: #{e}")
       end
 
       def timing(label, duration)
-        server.timing(prefix + '.' + label, duration)
+        server.timing("#{prefix}.#{label}", duration)
       rescue StandardError => e
         @logger.log('s', "[!] Failure updating timing #{prefix}.#{label} on statsd server [#{server}:#{port}]: #{e}")
       end
diff --git a/lib/vmpooler/pool_manager.rb b/lib/vmpooler/pool_manager.rb
index a7773f1..6e969ff 100644
--- a/lib/vmpooler/pool_manager.rb
+++ b/lib/vmpooler/pool_manager.rb
@@ -108,7 +108,7 @@ module Vmpooler
       $logger.log('d', "[!] [#{pool}] '#{vm}' no longer exists. Removing from pending.")
     end
 
-    def fail_pending_vm(vm, pool, timeout, redis, exists = true)
+    def fail_pending_vm(vm, pool, timeout, redis, exists: true)
       clone_stamp = redis.hget("vmpooler__vm__#{vm}", 'clone')
 
       time_since_clone = (Time.now - Time.parse(clone_stamp)) / 60
@@ -117,7 +117,7 @@ module Vmpooler
           request_id = redis.hget("vmpooler__vm__#{vm}", 'request_id')
           pool_alias = redis.hget("vmpooler__vm__#{vm}", 'pool_alias') if request_id
           redis.multi
-          redis.smove('vmpooler__pending__' + pool, 'vmpooler__completed__' + pool, vm)
+          redis.smove("vmpooler__pending__#{pool}", "vmpooler__completed__#{pool}", vm)
           redis.zadd('vmpooler__odcreate__task', 1, "#{pool_alias}:#{pool}:1:#{request_id}") if request_id
           redis.exec
           $metrics.increment("errors.markedasfailed.#{pool}")
@@ -133,15 +133,16 @@ module Vmpooler
     end
 
     def move_pending_vm_to_ready(vm, pool, redis, request_id = nil)
-      clone_time = redis.hget('vmpooler__vm__' + vm, 'clone')
+      clone_time = redis.hget("vmpooler__vm__#{vm}", 'clone')
       finish = format('%<time>.2f', time: Time.now - Time.parse(clone_time))
 
       if request_id
         ondemandrequest_hash = redis.hgetall("vmpooler__odrequest__#{request_id}")
-        if ondemandrequest_hash['status'] == 'failed'
+        case ondemandrequest_hash['status']
+        when 'failed'
           move_vm_queue(pool, vm, 'pending', 'completed', redis, "moved to completed queue. '#{request_id}' could not be filled in time")
           return nil
-        elsif ondemandrequest_hash['status'] == 'deleted'
+        when 'deleted'
           move_vm_queue(pool, vm, 'pending', 'completed', redis, "moved to completed queue. '#{request_id}' has been deleted")
           return nil
         end
@@ -160,11 +161,11 @@ module Vmpooler
         move_vm_queue(pool, vm, 'pending', 'running', redis)
         check_ondemand_request_ready(request_id, redis)
       else
-        redis.smove('vmpooler__pending__' + pool, 'vmpooler__ready__' + pool, vm)
+        redis.smove("vmpooler__pending__#{pool}", "vmpooler__ready__#{pool}", vm)
       end
 
       redis.pipelined do
-        redis.hset('vmpooler__boot__' + Date.today.to_s, pool + ':' + vm, finish) # maybe remove as this is never used by vmpooler itself?
+        redis.hset("vmpooler__boot__#{Date.today}", "#{pool}:#{vm}", finish) # maybe remove as this is never used by vmpooler itself?
         redis.hset("vmpooler__vm__#{vm}", 'ready', Time.now)
 
         # last boot time is displayed in API, and used by alarming script
@@ -203,11 +204,11 @@ module Vmpooler
 
       mutex.synchronize do
         @redis.with_metrics do |redis|
-          check_stamp = redis.hget('vmpooler__vm__' + vm, 'check')
+          check_stamp = redis.hget("vmpooler__vm__#{vm}", 'check')
           last_checked_too_soon = ((Time.now - Time.parse(check_stamp)).to_i < $config[:config]['vm_checktime'] * 60) if check_stamp
           break if check_stamp && last_checked_too_soon
 
-          redis.hset('vmpooler__vm__' + vm, 'check', Time.now)
+          redis.hset("vmpooler__vm__#{vm}", 'check', Time.now)
           # Check if the hosts TTL has expired
           # if 'boottime' is nil, set bootime to beginning of unix epoch, forces TTL to be assumed expired
           boottime = redis.hget("vmpooler__vm__#{vm}", 'ready')
@@ -217,7 +218,7 @@ module Vmpooler
             boottime = Time.at(0)
           end
           if (Time.now - boottime).to_i > ttl * 60
-            redis.smove('vmpooler__ready__' + pool_name, 'vmpooler__completed__' + pool_name, vm)
+            redis.smove("vmpooler__ready__#{pool_name}", "vmpooler__completed__#{pool_name}", vm)
 
             $logger.log('d', "[!] [#{pool_name}] '#{vm}' reached end of TTL after #{ttl} minutes, removed from 'ready' queue")
             return nil
@@ -256,7 +257,7 @@ module Vmpooler
       return if hostname.empty?
       return if hostname == vm
 
-      redis.smove('vmpooler__ready__' + pool_name, 'vmpooler__completed__' + pool_name, vm)
+      redis.smove("vmpooler__ready__#{pool_name}", "vmpooler__completed__#{pool_name}", vm)
       $logger.log('d', "[!] [#{pool_name}] '#{vm}' has mismatched hostname #{hostname}, removed from 'ready' queue")
       true
     end
@@ -280,7 +281,7 @@ module Vmpooler
         catch :stop_checking do
           @redis.with_metrics do |redis|
             # Check that VM is within defined lifetime
-            checkouttime = redis.hget('vmpooler__active__' + pool, vm)
+            checkouttime = redis.hget("vmpooler__active__#{pool}", vm)
             if checkouttime
               time_since_checkout = Time.now - Time.parse(checkouttime)
               running = time_since_checkout / 60 / 60
@@ -341,7 +342,7 @@ module Vmpooler
         adjective = @name_generator.adjective(max: 14 - noun.length)
         random_name = [adjective, noun].join('-')
         hostname = $config[:config]['prefix'] + random_name
-        available = redis.hlen('vmpooler__vm__' + hostname) == 0
+        available = redis.hlen("vmpooler__vm__#{hostname}") == 0
 
         [hostname, available]
       end
@@ -395,12 +396,12 @@ module Vmpooler
         @redis.with_metrics do |redis|
           # Add VM to Redis inventory ('pending' pool)
           redis.multi
-          redis.sadd('vmpooler__pending__' + pool_name, new_vmname)
-          redis.hset('vmpooler__vm__' + new_vmname, 'clone', Time.now)
-          redis.hset('vmpooler__vm__' + new_vmname, 'template', pool_name) # This value is used to represent the pool.
-          redis.hset('vmpooler__vm__' + new_vmname, 'pool', pool_name)
-          redis.hset('vmpooler__vm__' + new_vmname, 'request_id', request_id) if request_id
-          redis.hset('vmpooler__vm__' + new_vmname, 'pool_alias', pool_alias) if pool_alias
+          redis.sadd("vmpooler__pending__#{pool_name}", new_vmname)
+          redis.hset("vmpooler__vm__#{new_vmname}", 'clone', Time.now)
+          redis.hset("vmpooler__vm__#{new_vmname}", 'template', pool_name) # This value is used to represent the pool.
+          redis.hset("vmpooler__vm__#{new_vmname}", 'pool', pool_name)
+          redis.hset("vmpooler__vm__#{new_vmname}", 'request_id', request_id) if request_id
+          redis.hset("vmpooler__vm__#{new_vmname}", 'pool_alias', pool_alias) if pool_alias
           redis.exec
         end
 
@@ -412,8 +413,8 @@ module Vmpooler
 
           @redis.with_metrics do |redis|
             redis.pipelined do
-              redis.hset('vmpooler__clone__' + Date.today.to_s, pool_name + ':' + new_vmname, finish)
-              redis.hset('vmpooler__vm__' + new_vmname, 'clone_time', finish)
+              redis.hset("vmpooler__clone__#{Date.today}", "#{pool_name}:#{new_vmname}", finish)
+              redis.hset("vmpooler__vm__#{new_vmname}", 'clone_time', finish)
             end
           end
           $logger.log('s', "[+] [#{pool_name}] '#{new_vmname}' cloned in #{finish} seconds")
@@ -456,18 +457,18 @@ module Vmpooler
       mutex.synchronize do
         @redis.with_metrics do |redis|
           redis.pipelined do
-            redis.hdel('vmpooler__active__' + pool, vm)
-            redis.hset('vmpooler__vm__' + vm, 'destroy', Time.now)
+            redis.hdel("vmpooler__active__#{pool}", vm)
+            redis.hset("vmpooler__vm__#{vm}", 'destroy', Time.now)
 
             # Auto-expire metadata key
-            redis.expire('vmpooler__vm__' + vm, ($config[:redis]['data_ttl'].to_i * 60 * 60))
+            redis.expire("vmpooler__vm__#{vm}", ($config[:redis]['data_ttl'].to_i * 60 * 60))
           end
 
           start = Time.now
 
           provider.destroy_vm(pool, vm)
 
-          redis.srem('vmpooler__completed__' + pool, vm)
+          redis.srem("vmpooler__completed__#{pool}", vm)
 
           finish = format('%<time>.2f', time: Time.now - start)
           $logger.log('s', "[-] [#{pool}] '#{vm}' destroyed in #{finish} seconds")
@@ -603,10 +604,10 @@ module Vmpooler
 
       if result
         @redis.with_metrics do |redis|
-          rdisks = redis.hget('vmpooler__vm__' + vm_name, 'disk')
+          rdisks = redis.hget("vmpooler__vm__#{vm_name}", 'disk')
           disks = rdisks ? rdisks.split(':') : []
           disks.push("+#{disk_size}gb")
-          redis.hset('vmpooler__vm__' + vm_name, 'disk', disks.join(':'))
+          redis.hset("vmpooler__vm__#{vm_name}", 'disk', disks.join(':'))
         end
 
         $logger.log('s', "[+] [disk_manager] '#{vm_name}' attached #{disk_size}gb disk in #{finish} seconds")
@@ -638,7 +639,7 @@ module Vmpooler
 
       if result
         @redis.with_metrics do |redis|
-          redis.hset('vmpooler__vm__' + vm_name, 'snapshot:' + snapshot_name, Time.now.to_s)
+          redis.hset("vmpooler__vm__#{vm_name}", "snapshot:#{snapshot_name}", Time.now.to_s)
         end
         $logger.log('s', "[+] [snapshot_manager] '#{vm_name}' snapshot created in #{finish} seconds")
       else
@@ -697,7 +698,7 @@ module Vmpooler
 
     def get_pool_name_for_vm(vm_name, redis)
       # the 'template' is a bad name.  Should really be 'poolname'
-      redis.hget('vmpooler__vm__' + vm_name, 'template')
+      redis.hget("vmpooler__vm__#{vm_name}", 'template')
     end
 
     # @param pool_name [String] - the name of the pool
@@ -867,16 +868,12 @@ module Vmpooler
 
             if options[:clone_target_change]
               clone_target = redis.hget('vmpooler__config__clone_target}', options[:poolname])
-              if clone_target
-                break unless clone_target == initial_clone_target
-              end
+              break if clone_target && !clone_target == initial_clone_target
             end
 
             if options[:pool_template_change]
               configured_template = redis.hget('vmpooler__config__template', options[:poolname])
-              if configured_template
-                break unless initial_template == configured_template
-              end
+              break if configured_template && initial_template != configured_template
             end
 
             if options[:pool_reset]
@@ -970,21 +967,17 @@ module Vmpooler
     def sync_pool_template(pool)
       @redis.with_metrics do |redis|
         pool_template = redis.hget('vmpooler__config__template', pool['name'])
-        if pool_template
-          pool['template'] = pool_template unless pool['template'] == pool_template
-        end
+        pool['template'] = pool_template if pool_template && pool['template'] != pool_template
       end
     end
 
     def prepare_template(pool, provider, redis)
-      if $config[:config]['create_template_delta_disks']
-        unless redis.sismember('vmpooler__template__deltas', pool['template'])
-          begin
-            provider.create_template_delta_disks(pool)
-            redis.sadd('vmpooler__template__deltas', pool['template'])
-          rescue StandardError => e
-            $logger.log('s', "[!] [#{pool['name']}] failed while preparing a template with an error. As a result vmpooler could not create the template delta disks. Either a template delta disk already exists, or the template delta disk creation failed. The error is: #{e}")
-          end
+      if $config[:config]['create_template_delta_disks'] && !redis.sismember('vmpooler__template__deltas', pool['template'])
+        begin
+          provider.create_template_delta_disks(pool)
+          redis.sadd('vmpooler__template__deltas', pool['template'])
+        rescue StandardError => e
+          $logger.log('s', "[!] [#{pool['name']}] failed while preparing a template with an error. As a result vmpooler could not create the template delta disks. Either a template delta disk already exists, or the template delta disk creation failed. The error is: #{e}")
         end
       end
       redis.hset('vmpooler__template__prepared', pool['name'], pool['template'])
@@ -1135,15 +1128,15 @@ module Vmpooler
         mutex.synchronize do
           @redis.with_metrics do |redis|
             provider.vms_in_pool(pool['name']).each do |vm|
-              if !redis.sismember('vmpooler__running__' + pool['name'], vm['name']) &&
-                 !redis.sismember('vmpooler__ready__' + pool['name'], vm['name']) &&
-                 !redis.sismember('vmpooler__pending__' + pool['name'], vm['name']) &&
-                 !redis.sismember('vmpooler__completed__' + pool['name'], vm['name']) &&
-                 !redis.sismember('vmpooler__discovered__' + pool['name'], vm['name']) &&
-                 !redis.sismember('vmpooler__migrating__' + pool['name'], vm['name'])
+              if !redis.sismember("vmpooler__running__#{pool['name']}", vm['name']) &&
+                 !redis.sismember("vmpooler__ready__#{pool['name']}", vm['name']) &&
+                 !redis.sismember("vmpooler__pending__#{pool['name']}", vm['name']) &&
+                 !redis.sismember("vmpooler__completed__#{pool['name']}", vm['name']) &&
+                 !redis.sismember("vmpooler__discovered__#{pool['name']}", vm['name']) &&
+                 !redis.sismember("vmpooler__migrating__#{pool['name']}", vm['name'])
 
                 pool_check_response[:discovered_vms] += 1
-                redis.sadd('vmpooler__discovered__' + pool['name'], vm['name'])
+                redis.sadd("vmpooler__discovered__#{pool['name']}", vm['name'])
 
                 $logger.log('s', "[?] [#{pool['name']}] '#{vm['name']}' added to 'discovered' queue")
               end
@@ -1164,7 +1157,7 @@ module Vmpooler
         redis.smembers("vmpooler__running__#{pool_name}").each do |vm|
           if inventory[vm]
             begin
-              vm_lifetime = redis.hget('vmpooler__vm__' + vm, 'lifetime') || $config[:config]['vm_lifetime'] || 12
+              vm_lifetime = redis.hget("vmpooler__vm__#{vm}", 'lifetime') || $config[:config]['vm_lifetime'] || 12
               pool_check_response[:checked_running_vms] += 1
               check_running_vm(vm, pool_name, vm_lifetime, provider)
             rescue StandardError => e
@@ -1206,7 +1199,7 @@ module Vmpooler
               $logger.log('d', "[!] [#{pool_name}] _check_pool failed with an error while evaluating pending VMs: #{e}")
             end
           else
-            fail_pending_vm(vm, pool_name, pool_timeout, redis, false)
+            fail_pending_vm(vm, pool_name, pool_timeout, redis, exists: false)
           end
         end
       end
diff --git a/lib/vmpooler/providers/dummy.rb b/lib/vmpooler/providers/dummy.rb
index c4ea7cc..0a1a60d 100644
--- a/lib/vmpooler/providers/dummy.rb
+++ b/lib/vmpooler/providers/dummy.rb
@@ -79,7 +79,7 @@ module Vmpooler
           return current_vm['vm_host'] if rand(1..100) > provider_config['migratevm_couldmove_percent']
 
           # Simulate a 10 node cluster and randomly pick a different one
-          new_host = 'HOST' + rand(1..10).to_s while new_host == current_vm['vm_host']
+          new_host = "HOST#{rand(1..10)}" while new_host == current_vm['vm_host']
 
           new_host
         end
@@ -95,9 +95,7 @@ module Vmpooler
             end
 
             # Inject clone failure
-            unless provider_config['migratevm_fail_percent'].nil?
-              raise('Dummy Failure for migratevm_fail_percent') if rand(1..100) <= provider_config['migratevm_fail_percent']
-            end
+            raise('Dummy Failure for migratevm_fail_percent') if !provider_config['migratevm_fail_percent'].nil? && rand(1..100) <= provider_config['migratevm_fail_percent']
 
             @write_lock.synchronize do
               current_vm = get_dummy_vm(pool_name, vm_name)
@@ -116,27 +114,23 @@ module Vmpooler
             return nil if dummy.nil?
 
             # Randomly power off the VM
-            unless dummy['powerstate'] != 'PoweredOn' || provider_config['getvm_poweroff_percent'].nil?
-              if rand(1..100) <= provider_config['getvm_poweroff_percent']
-                @write_lock.synchronize do
-                  dummy = get_dummy_vm(pool_name, vm_name)
-                  dummy['powerstate'] = 'PoweredOff'
-                  write_backing_file
-                end
-                logger.log('d', "[ ] [#{dummy['poolname']}] '#{dummy['name']}' is being Dummy Powered Off")
+            if !(dummy['powerstate'] != 'PoweredOn' || provider_config['getvm_poweroff_percent'].nil?) && rand(1..100) <= provider_config['getvm_poweroff_percent']
+              @write_lock.synchronize do
+                dummy = get_dummy_vm(pool_name, vm_name)
+                dummy['powerstate'] = 'PoweredOff'
+                write_backing_file
               end
+              logger.log('d', "[ ] [#{dummy['poolname']}] '#{dummy['name']}' is being Dummy Powered Off")
             end
 
             # Randomly rename the host
-            unless dummy['hostname'] != dummy['name'] || provider_config['getvm_rename_percent'].nil?
-              if rand(1..100) <= provider_config['getvm_rename_percent']
-                @write_lock.synchronize do
-                  dummy = get_dummy_vm(pool_name, vm_name)
-                  dummy['hostname'] = 'DUMMY' + dummy['name']
-                  write_backing_file
-                end
-                logger.log('d', "[ ] [#{dummy['poolname']}] '#{dummy['name']}' is being Dummy renamed")
+            if !(dummy['hostname'] != dummy['name'] || provider_config['getvm_rename_percent'].nil?) && rand(1..100) <= provider_config['getvm_rename_percent']
+              @write_lock.synchronize do
+                dummy = get_dummy_vm(pool_name, vm_name)
+                dummy['hostname'] = "DUMMY#{dummy['name']}"
+                write_backing_file
               end
+              logger.log('d', "[ ] [#{dummy['poolname']}] '#{dummy['name']}' is being Dummy renamed")
             end
 
             obj['name'] = dummy['name']
@@ -196,9 +190,7 @@ module Vmpooler
 
             begin
               # Inject clone failure
-              unless provider_config['createvm_fail_percent'].nil?
-                raise('Dummy Failure for createvm_fail_percent') if rand(1..100) <= provider_config['createvm_fail_percent']
-              end
+              raise('Dummy Failure for createvm_fail_percent') if !provider_config['createvm_fail_percent'].nil? && rand(1..100) <= provider_config['createvm_fail_percent']
 
               # Assert the VM is ready for use
               @write_lock.synchronize do
@@ -229,9 +221,7 @@ module Vmpooler
             end
 
             # Inject create failure
-            unless provider_config['createdisk_fail_percent'].nil?
-              raise('Dummy Failure for createdisk_fail_percent') if rand(1..100) <= provider_config['createdisk_fail_percent']
-            end
+            raise('Dummy Failure for createdisk_fail_percent') if !provider_config['createdisk_fail_percent'].nil? && rand(1..100) <= provider_config['createdisk_fail_percent']
 
             @write_lock.synchronize do
               vm_object = get_dummy_vm(pool_name, vm_name)
@@ -255,9 +245,7 @@ module Vmpooler
             end
 
             # Inject create failure
-            unless provider_config['createsnapshot_fail_percent'].nil?
-              raise('Dummy Failure for createsnapshot_fail_percent') if rand(1..100) <= provider_config['createsnapshot_fail_percent']
-            end
+            raise('Dummy Failure for createsnapshot_fail_percent') if !provider_config['createsnapshot_fail_percent'].nil? && rand(1..100) <= provider_config['createsnapshot_fail_percent']
 
             @write_lock.synchronize do
               vm_object = get_dummy_vm(pool_name, vm_name)
@@ -282,9 +270,7 @@ module Vmpooler
             end
 
             # Inject create failure
-            unless provider_config['revertsnapshot_fail_percent'].nil?
-              raise('Dummy Failure for revertsnapshot_fail_percent') if rand(1..100) <= provider_config['revertsnapshot_fail_percent']
-            end
+            raise('Dummy Failure for revertsnapshot_fail_percent') if !provider_config['revertsnapshot_fail_percent'].nil? && rand(1..100) <= provider_config['revertsnapshot_fail_percent']
           end
 
           vm_object['snapshots'].include?(snapshot_name)
@@ -320,9 +306,7 @@ module Vmpooler
             end
 
             # Inject destroy VM failure
-            unless provider_config['destroyvm_fail_percent'].nil?
-              raise('Dummy Failure for migratevm_fail_percent') if rand(1..100) <= provider_config['destroyvm_fail_percent']
-            end
+            raise('Dummy Failure for migratevm_fail_percent') if !provider_config['destroyvm_fail_percent'].nil? && rand(1..100) <= provider_config['destroyvm_fail_percent']
 
             # 'Destroy' the VM
             @write_lock.synchronize do
@@ -354,9 +338,7 @@ module Vmpooler
             # it's ready to receive a connection
             sleep(2)
 
-            unless provider_config['vmready_fail_percent'].nil?
-              raise('Dummy Failure for vmready_fail_percent') if rand(1..100) <= provider_config['vmready_fail_percent']
-            end
+            raise('Dummy Failure for vmready_fail_percent') if !provider_config['vmready_fail_percent'].nil? && rand(1..100) <= provider_config['vmready_fail_percent']
 
             @write_lock.synchronize do
               vm_object['ready'] = true
diff --git a/lib/vmpooler/providers/vsphere.rb b/lib/vmpooler/providers/vsphere.rb
index 467a6b2..1933f64 100644
--- a/lib/vmpooler/providers/vsphere.rb
+++ b/lib/vmpooler/providers/vsphere.rb
@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 require 'vmpooler/providers/base'
+require 'bigdecimal'
+require 'bigdecimal/util'
 
 module Vmpooler
   class PoolManager
@@ -49,9 +51,7 @@ module Vmpooler
         end
 
         def folder_configured?(folder_title, base_folder, configured_folders, whitelist)
-          if whitelist
-            return true if whitelist.include?(folder_title)
-          end
+          return true if whitelist&.include?(folder_title)
           return false unless configured_folders.keys.include?(folder_title)
           return false unless configured_folders[folder_title] == base_folder
 
@@ -68,7 +68,7 @@ module Vmpooler
             redis.hset("vmpooler__vm__#{vm_name}", 'destroy', Time.now)
 
             # Auto-expire metadata key
-            redis.expire('vmpooler__vm__' + vm_name, (data_ttl * 60 * 60))
+            redis.expire("vmpooler__vm__#{vm_name}", (data_ttl * 60 * 60))
             redis.exec
           end
 
@@ -203,9 +203,7 @@ module Vmpooler
             return
           end
           wait_for_host_selection(dc, target, loop_delay, max_age) if target[dc].key?('checking')
-          if target[dc].key?('check_time_finished')
-            select_target_hosts(target, cluster, datacenter) if now - target[dc]['check_time_finished'] > max_age
-          end
+          select_target_hosts(target, cluster, datacenter) if target[dc].key?('check_time_finished') && now - target[dc]['check_time_finished'] > max_age
         end
 
         def wait_for_host_selection(dc, target, maxloop = 0, loop_delay = 1, max_age = 60)
@@ -418,15 +416,15 @@ module Vmpooler
           # Determine network device type
           # All possible device type options here: https://vdc-download.vmware.com/vmwb-repository/dcr-public/98d63b35-d822-47fe-a87a-ddefd469df06/2e3c7b58-f2bd-486e-8bb1-a75eb0640bee/doc/vim.vm.device.VirtualEthernetCard.html
           network_device =
-            if template_vm_network_device.is_a? RbVmomi::VIM::VirtualVmxnet2
+            if template_vm_network_device.instance_of? RbVmomi::VIM::VirtualVmxnet2
               RbVmomi::VIM.VirtualVmxnet2
-            elsif template_vm_network_device.is_a? RbVmomi::VIM::VirtualVmxnet3
+            elsif template_vm_network_device.instance_of? RbVmomi::VIM::VirtualVmxnet3
               RbVmomi::VIM.VirtualVmxnet3
-            elsif template_vm_network_device.is_a? RbVmomi::VIM::VirtualE1000
+            elsif template_vm_network_device.instance_of? RbVmomi::VIM::VirtualE1000
               RbVmomi::VIM.VirtualE1000
-            elsif template_vm_network_device.is_a? RbVmomi::VIM::VirtualE1000e
+            elsif template_vm_network_device.instance_of? RbVmomi::VIM::VirtualE1000e
               RbVmomi::VIM.VirtualE1000e
-            elsif template_vm_network_device.is_a? RbVmomi::VIM::VirtualSriovEthernetCard
+            elsif template_vm_network_device.instance_of? RbVmomi::VIM::VirtualSriovEthernetCard
               RbVmomi::VIM.VirtualSriovEthernetCard
             else
               RbVmomi::VIM.VirtualPCNet32
@@ -560,7 +558,7 @@ module Vmpooler
           boottime = vm_object.runtime.bootTime if vm_object.runtime&.bootTime
           powerstate = vm_object.runtime.powerState if vm_object.runtime&.powerState
 
-          hash = {
+          {
             'name' => vm_object.name,
             'hostname' => hostname,
             'template' => pool_configuration['template'],
@@ -568,8 +566,6 @@ module Vmpooler
             'boottime' => boottime,
             'powerstate' => powerstate
           }
-
-          hash
         end
 
         # vSphere helper methods
@@ -794,7 +790,7 @@ module Vmpooler
           }
 
           folder_object = connection.searchIndex.FindByInventoryPath(propSpecs) # rubocop:disable Naming/VariableName
-          return nil unless folder_object.class == RbVmomi::VIM::Folder
+          return nil unless folder_object.instance_of? RbVmomi::VIM::Folder
 
           folder_object
         end
@@ -810,9 +806,7 @@ module Vmpooler
         #    the cpu or memory utilization is bigger than the limit param
         def get_host_utilization(host, model = nil, limit = 90)
           limit = @config[:config]['utilization_limit'] if @config[:config].key?('utilization_limit')
-          if model
-            return nil unless host_has_cpu_model?(host, model)
-          end
+          return nil if model && !host_has_cpu_model?(host, model)
           return nil if host.runtime.inMaintenanceMode
           return nil unless host.overallStatus == 'green'
           return nil unless host.configIssue.empty?
@@ -821,9 +815,9 @@ module Vmpooler
           memory_utilization = memory_utilization_for host
 
           return nil if cpu_utilization.nil?
-          return nil if cpu_utilization == 0.0
+          return nil if cpu_utilization.to_d == 0.0.to_d
           return nil if memory_utilization.nil?
-          return nil if memory_utilization == 0.0
+          return nil if memory_utilization.to_d == 0.0.to_d
 
           return nil if cpu_utilization > limit
           return nil if memory_utilization > limit
@@ -838,8 +832,7 @@ module Vmpooler
         def get_host_cpu_arch_version(host)
           cpu_model = host.hardware.cpuPkg[0].description
           cpu_model_parts = cpu_model.split
-          arch_version = cpu_model_parts[4]
-          arch_version
+          cpu_model_parts[4]
         end
 
         def cpu_utilization_for(host)
@@ -931,8 +924,7 @@ module Vmpooler
           target_hosts = get_cluster_host_utilization(cluster_object)
           raise("There is no host candidate in vcenter that meets all the required conditions, check that the cluster has available hosts in a 'green' status, not in maintenance mode and not overloaded CPU and memory'") if target_hosts.empty?
 
-          least_used_host = target_hosts.min[1]
-          least_used_host
+          target_hosts.min[1]
         end
 
         def find_cluster(cluster, connection, datacentername)
@@ -979,11 +971,10 @@ module Vmpooler
         end
 
         def build_propSpecs(datacenter, folder, vmname) # rubocop:disable Naming/MethodName
-          propSpecs = { # rubocop:disable Naming/VariableName
+          {
             entity => self,
             :inventoryPath => "#{datacenter}/vm/#{folder}/#{vmname}"
           }
-          propSpecs # rubocop:disable Naming/VariableName
         end
 
         def find_vm(pool_name, vmname, connection)
diff --git a/spec/rbvmomi_helper.rb b/spec/rbvmomi_helper.rb
index f8c8a1a..e0acbaf 100644
--- a/spec/rbvmomi_helper.rb
+++ b/spec/rbvmomi_helper.rb
@@ -588,7 +588,7 @@ def mock_RbVmomi_VIM_VirtualVmxnet3(options = {})
   mock.addressType = options[:addressType]
   mock.connectable = options[:connectable]
 
-  allow(mock).to receive(:is_a?) do |expected_type|
+  allow(mock).to receive(:instance_of?) do |expected_type|
     expected_type == RbVmomi::VIM::VirtualVmxnet3
   end
 
diff --git a/spec/unit/pool_manager_spec.rb b/spec/unit/pool_manager_spec.rb
index 3fb44da..ff74d56 100644
--- a/spec/unit/pool_manager_spec.rb
+++ b/spec/unit/pool_manager_spec.rb
@@ -185,7 +185,7 @@ EOT
     it 'moves VM to completed queue if VM has exceeded timeout and exists' do
       redis_connection_pool.with do |redis|
         redis.hset("vmpooler__vm__#{vm}", 'clone',Date.new(2001,1,1).to_s)
-        expect(subject.fail_pending_vm(vm, pool, timeout, redis, true)).to eq(true)
+        expect(subject.fail_pending_vm(vm, pool, timeout, redis, exists: true)).to eq(true)
         expect(redis.sismember("vmpooler__pending__#{pool}", vm)).to be(false)
         expect(redis.sismember("vmpooler__completed__#{pool}", vm)).to be(true)
       end
@@ -195,7 +195,7 @@ EOT
       redis_connection_pool.with do |redis|
         redis.hset("vmpooler__vm__#{vm}", 'clone',Date.new(2001,1,1).to_s)
         expect(logger).to receive(:log).with('d', "[!] [#{pool}] '#{vm}' marked as 'failed' after #{timeout} minutes")
-        expect(subject.fail_pending_vm(vm, pool, timeout, redis, true)).to eq(true)
+        expect(subject.fail_pending_vm(vm, pool, timeout, redis, exists: true)).to eq(true)
       end
     end
 
@@ -203,14 +203,14 @@ EOT
       redis_connection_pool.with do |redis|
         redis.hset("vmpooler__vm__#{vm}", 'clone',Date.new(2001,1,1).to_s)
         expect(subject).to receive(:remove_nonexistent_vm).with(vm, pool, redis)
-        expect(subject.fail_pending_vm(vm, pool, timeout, redis, false)).to eq(true)
+        expect(subject.fail_pending_vm(vm, pool, timeout, redis, exists: false)).to eq(true)
       end
     end
 
     it 'swallows error if an error is raised' do
       redis_connection_pool.with do |redis|
         redis.hset("vmpooler__vm__#{vm}", 'clone','iamnotparsable_asdate')
-        expect(subject.fail_pending_vm(vm, pool, timeout, redis, true)).to eq(false)
+        expect(subject.fail_pending_vm(vm, pool, timeout, redis, exists: true)).to eq(false)
       end
     end
 
@@ -219,7 +219,7 @@ EOT
         redis.hset("vmpooler__vm__#{vm}", 'clone','iamnotparsable_asdate')
         expect(logger).to receive(:log).with('d', String)
 
-        subject.fail_pending_vm(vm, pool, timeout, redis, true)
+        subject.fail_pending_vm(vm, pool, timeout, redis, exists: true)
       end
     end
 
@@ -230,7 +230,7 @@ EOT
           redis.hset("vmpooler__vm__#{vm}", 'clone',(Time.now - 900).to_s)
           redis.hset("vmpooler__vm__#{vm}", 'pool_alias', pool)
           redis.hset("vmpooler__vm__#{vm}", 'request_id', request_id)
-          subject.fail_pending_vm(vm, pool, timeout, redis, true)
+          subject.fail_pending_vm(vm, pool, timeout, redis, exists: true)
           expect(redis.zrange('vmpooler__odcreate__task', 0, -1)).to eq(["#{pool}:#{pool}:1:#{request_id}"])
         end
       end
@@ -3950,7 +3950,7 @@ EOT
 
       it 'should call fail_pending_vm' do
         redis_connection_pool.with do |redis|
-          expect(subject).to receive(:fail_pending_vm).with(vm,pool,Integer,redis,false)
+          expect(subject).to receive(:fail_pending_vm).with(vm, pool, Integer, redis, exists: false)
         end
 
         subject.check_pending_pool_vms(pool, provider, pool_check_response, inventory, timeout)
diff --git a/spec/unit/providers/vsphere_spec.rb b/spec/unit/providers/vsphere_spec.rb
index 751a7ec..eaf4e09 100644
--- a/spec/unit/providers/vsphere_spec.rb
+++ b/spec/unit/providers/vsphere_spec.rb
@@ -1585,7 +1585,7 @@ EOT
       expect(result.location.datastore.name).to eq('datastore0')
       expect(result.location.diskMoveType).to eq(:moveChildMostDiskBacking)
       expect(result.config.deviceChange.first[:operation]).to eq(:edit)
-      expect(result.config.deviceChange.first[:device].is_a?(RbVmomi::VIM::VirtualVmxnet3)).to be true
+      expect(result.config.deviceChange.first[:device].instance_of?(RbVmomi::VIM::VirtualVmxnet3)).to be true
     end
   end
 
@@ -1885,7 +1885,7 @@ EOT
 
       it 'should return the folder when found' do
         allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(folder_object)
-        allow(folder_object).to receive(:class).and_return(RbVmomi::VIM::Folder)
+        allow(folder_object).to receive(:instance_of?).and_return(RbVmomi::VIM::Folder)
         result = subject.find_vm_folder(poolname,connection)
         expect(result.name).to eq(foldername)
       end
@@ -1901,7 +1901,7 @@ EOT
 
       it 'should return the folder when found' do
         allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(folder_object)
-        allow(folder_object).to receive(:class).and_return(RbVmomi::VIM::Folder)
+        allow(folder_object).to receive(:instance_of?).and_return(RbVmomi::VIM::Folder)
         result = subject.find_vm_folder(poolname,connection)
         expect(result.name).to eq(foldername)
       end
@@ -1918,7 +1918,7 @@ EOT
 
       it 'should return the folder when found' do
         allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(folder_object)
-        allow(folder_object).to receive(:class).and_return(RbVmomi::VIM::Folder)
+        allow(folder_object).to receive(:instance_of?).and_return(RbVmomi::VIM::Folder)
         result = subject.find_vm_folder(poolname,connection)
         expect(result.name).to eq(foldername)
       end
diff --git a/vmpooler.gemspec b/vmpooler.gemspec
index 39127d3..35abb9c 100644
--- a/vmpooler.gemspec
+++ b/vmpooler.gemspec
@@ -45,7 +45,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency 'pry'
   s.add_development_dependency 'rack-test', '>= 0.6'
   s.add_development_dependency 'rspec', '>= 3.2'
-  s.add_development_dependency 'rubocop', '< 1.0'
+  s.add_development_dependency 'rubocop', '~> 1.0'
   s.add_development_dependency 'simplecov', '>= 0.11.2'
   s.add_development_dependency 'yarjuf', '>= 2.0'
 end