updated emit_cadvisor_metrics (#103)

* updated emit_cadvisor_metrics

Author: hvaghani221

lib/fluent/plugin/in_kubernetes_metrics.rb

@@ -602,33 +602,34 @@ def emit_stats_metrics(metrics)
         emit_stats_breakdown(metrics['stats']) unless metrics['stats'].nil?
       end
 
+      # Make sure regex has only one capturing group
+      def grep_using_regex(metric, regex)
+        match = metric.match(regex)
+        return nil if match.nil?
+        match[1]
+      end
+
       def emit_cadvisor_metrics(metrics)
         metrics = metrics.split("\n")
         metrics.each do |metric|
-          next unless metric.include? 'container_name='
-
-          next unless metric.match(/^((?!container_name="").)*$/) && metric[0] != '#'
-
+          
+          next if metric[0] == '#' or not container_name = grep_using_regex(metric, /container(?:_name)?="([^"]*)"/)
+          
           metric_str, metric_val = metric.split(' ')
           metric_val = metric_val.to_f if metric_val.is_a? String
           first_occur = metric_str.index('{')
           metric_name = metric_str[0..first_occur - 1]
-          pod_name = metric.match(/pod_name="\S*"/).to_s
-          pod_name = pod_name.split('"')[1]
-          image_name = metric.match(/image="\S*"/).to_s
-          image_name = image_name.split('"')[1]
-          namespace = metric.match(/namespace="\S*"/).to_s
-          namespace = namespace.split('"')[1]
+          pod_name = grep_using_regex(metric, /pod(?:_name)?="([^"]*)"/).to_s
+          image_name = grep_using_regex(metric, /image="([^"]*)"/).to_s
+          namespace = grep_using_regex(metric, /namespace="([^"]*)"/).to_s
           metric_labels = { 'pod_name' => pod_name, 'image' => image_name, 'namespace' => namespace, 'value' => metric_val, 'node' => @node_name }
-          if metric =~ /^((?!container_name="POD").)*$/
+          if container_name=="POD"
             tag = 'pod'
             tag = generate_tag("#{tag}#{metric_name.tr('_', '.')}")
             tag = tag.gsub('container', '')
           else
-            container_name = metric.match(/container_name="\S*"/).to_s
-            container_name = container_name.split('"')[1]
             container_label = { 'container_name' => container_name }
-            metric_labels.merge(container_label)
+            metric_labels.merge!(container_label)
             tag = generate_tag(metric_name.tr('_', '.').to_s)
           end
           router.emit tag, @scraped_at_cadvisor, metric_labels

test/plugin/test_in_kubernetes_metrics.rb

@@ -35,6 +35,9 @@ class KubernetesMetricsInputTest < Test::Unit::TestCase
   ).freeze
 
   setup do
+    stub_k8s_requests
+
+    return unless @@hash_map_test.empty?
     Fluent::Test.setup
 
     @@parsed_unit_string = JSON.parse(get_unit_parsed_string)
@@ -45,8 +48,6 @@ class KubernetesMetricsInputTest < Test::Unit::TestCase
       get_cadvisor_parsed_string = f.read
     end.close
 
-    stub_k8s_requests
-
     @@ca_driver = create_driver
     @@ca_driver.run timeout: 20, expect_emits: 1, shutdown: true
 
@@ -56,8 +57,10 @@ class KubernetesMetricsInputTest < Test::Unit::TestCase
     metrics = get_cadvisor_parsed_string.split("\n")
     metrics.each do |metric|
       next unless metric.include? 'container_name='
+      next unless  metric[0] != '#'
 
-      next unless metric.match(/^((?!container_name="").)*$/) && metric[0] != '#'
+      container_name = metric.match(/container_name="\S*"/).to_s
+      container_name = container_name.split('"')[1]
 
       metric_str, metric_val = metric.split(' ')
       metric_val = metric_val.to_f if metric_val.is_a? String
@@ -70,13 +73,11 @@ class KubernetesMetricsInputTest < Test::Unit::TestCase
       namespace = metric.match(/namespace="\S*"/).to_s
       namespace = namespace.split('"')[1]
       metric_labels = { 'pod_name' => pod_name, 'image' => image_name, 'namespace' => namespace, 'value' => metric_val, 'node' => @node_name }
-      if metric =~ /^((?!container_name="POD").)*$/
+      if container_name == 'POD'
         tag = 'pod'
         tag = generate_tag("#{tag}#{metric_name.tr('_', '.')}", @@driver.instance.tag)
         tag = tag.gsub('container', '')
       else
-        container_name = metric.match(/container_name="\S*"/).to_s
-        container_name = container_name.split('"')[1]
         container_label = { 'container_name' => container_name }
         metric_labels.merge(container_label)
         tag = generate_tag(metric_name.tr('_', '.').to_s, @@driver.instance.tag)
@@ -252,11 +253,10 @@ def create_driver(conf = CONFIG)
       assert_true @@hash_map_cadvisor.key?('kube.container.fs.read.seconds.total')
       assert_equal @@hash_map_cadvisor['kube.container.fs.read.seconds.total'], @@hash_map_test['kube.container.fs.read.seconds.total'][2]['value']
     end
-
-    # TODO: Current Test does not work - metric present in metrics_cadvisor.txt but not being parsed by connector in test/working in production
+    
     test 'Test - metrics cadvisor: container_fs_reads_bytes_total' do
-      assert_false @@hash_map_cadvisor.key?('kube.container.fs.reads.bytes.total')
-      # assert_equal @@hash_map_cadvisor['kube.container.fs.reads.bytes.total'], @@hash_map_test["kube.container.fs.reads.bytes.total"][2]["value"]
+      assert_true @@hash_map_cadvisor.key?('kube.container.fs.reads.bytes.total')
+      assert_equal @@hash_map_cadvisor['kube.container.fs.reads.bytes.total'], @@hash_map_test["kube.container.fs.reads.bytes.total"][2]["value"]
     end
 
     test 'Test - metrics cadvisor: container_fs_reads_merged_total' do
@@ -289,10 +289,9 @@ def create_driver(conf = CONFIG)
       assert_equal @@hash_map_cadvisor['kube.container.fs.write.seconds.total'], @@hash_map_test['kube.container.fs.write.seconds.total'][2]['value']
     end
 
-    # TODO: Current Test does not work - metric present in metrics_cadvisor.txt but not being parsed by connector in test/working in production
     test 'Test - metrics cadvisor: container_fs_writes_bytes_total' do
-      assert_false @@hash_map_cadvisor.key?('kube.container.fs.writes.bytes.total')
-      # assert_equal @@hash_map_cadvisor['kube.container.fs.writes.bytes.total'], @@hash_map_test["kube.container.fs.writes.bytes.total"][2]["value"]
+      assert_true @@hash_map_cadvisor.key?('kube.container.fs.writes.bytes.total')
+      assert_equal @@hash_map_cadvisor['kube.container.fs.writes.bytes.total'], @@hash_map_test["kube.container.fs.writes.bytes.total"][2]["value"]
     end
 
     test 'Test - metrics cadvisor: container_fs_writes_merged_total' do