Implement network stats.

plugins/elasticsearch/elasticsearch.go

@@ -20,6 +20,7 @@ type node struct {
 	Process    interface{}       `json:"process"`
 	JVM        interface{}       `json:"jvm"`
 	ThreadPool interface{}       `json:"thread_pool"`
+	Network    interface{}       `json:"network"`
 }
 
 const sampleConfig = `
@@ -115,6 +116,9 @@ func (e *Elasticsearch) gatherUrl(url string, acc plugins.Accumulator) error {
 		if err := e.parseInterface(acc, "thread_pool", tags, n.ThreadPool); err != nil {
 			return err
 		}
+		if err := e.parseInterface(acc, "network", tags, n.Network); err != nil {
+			return err
+		}
 	}
 
 	return nil

plugins/elasticsearch/elasticsearch_test.go

@@ -70,4 +70,8 @@ func TestElasticsearch(t *testing.T) {
 	for key, val := range threadPoolExpected {
 		assert.NoError(t, acc.ValidateTaggedValue(key, val, tags))
 	}
+
+	for key, val := range networkExpected {
+		assert.NoError(t, acc.ValidateTaggedValue(key, val, tags))
+	}
 }

plugins/elasticsearch/testdata_test.go

@@ -367,6 +367,20 @@ const statsResponse = `
           "largest": 1,
           "completed": 0
         }
+      },
+      "network": {
+        "tcp": {
+          "active_opens": 13,
+          "passive_opens": 16,
+          "curr_estab": 29,
+          "in_segs": 113,
+          "out_segs": 97,
+          "retrans_segs": 0,
+          "estab_resets": 0,
+          "attempt_fails": 0,
+          "in_errs": 0,
+          "out_rsts": 0
+        }
       }
     }
   }
@@ -614,3 +628,16 @@ var threadPoolExpected = map[string]float64{
 	"thread_pool_flush_largest":                 5,
 	"thread_pool_flush_completed":               3,
 }
+
+var networkExpected = map[string]float64{
+	"network_tcp_in_errs":       0,
+	"network_tcp_passive_opens": 16,
+	"network_tcp_curr_estab":    29,
+	"network_tcp_in_segs":       113,
+	"network_tcp_out_segs":      97,
+	"network_tcp_retrans_segs":  0,
+	"network_tcp_attempt_fails": 0,
+	"network_tcp_active_opens":  13,
+	"network_tcp_estab_resets":  0,
+	"network_tcp_out_rsts":      0,
+}