Add node roles tag to elasticsearch input (#6064)

plugins/inputs/elasticsearch/elasticsearch.go

@@ -6,6 +6,7 @@ import (
 	"io/ioutil"
 	"net/http"
 	"regexp"
+	"sort"
 	"strings"
 	"sync"
 	"time"
@@ -27,6 +28,7 @@ const statsPathLocal = "/_nodes/_local/stats"
 type nodeStat struct {
 	Host       string            `json:"host"`
 	Name       string            `json:"name"`
+	Roles      []string          `json:"roles"`
 	Attributes map[string]string `json:"attributes"`
 	Indices    interface{}       `json:"indices"`
 	OS         interface{}       `json:"os"`
@@ -326,11 +328,13 @@ func (e *Elasticsearch) gatherNodeStats(url string, acc telegraf.Accumulator) er
 	}
 
 	for id, n := range nodeStats.Nodes {
+		sort.Strings(n.Roles)
 		tags := map[string]string{
 			"node_id":      id,
 			"node_host":    n.Host,
 			"node_name":    n.Name,
 			"cluster_name": nodeStats.ClusterName,
+			"node_roles":   strings.Join(n.Roles, ","),
 		}
 
 		for k, v := range n.Attributes {

plugins/inputs/elasticsearch/elasticsearch_test.go

@@ -21,6 +21,7 @@ func defaultTags() map[string]string {
 		"node_id":               "SDFsfSDFsdfFSDSDfSFDSDF",
 		"node_name":             "test.host.com",
 		"node_host":             "test",
+		"node_roles":            "data,ingest,master",
 	}
 }
 func defaultServerInfo() serverInfo {

plugins/inputs/elasticsearch/testdata_test.go

@@ -117,6 +117,11 @@ const nodeStatsResponse = `
         "inet[/127.0.0.1:9300]",
         "NONE"
       ],
+      "roles": [
+        "master",
+        "data",
+        "ingest"
+      ],
       "attributes": {
         "master": "true"
       },
@@ -945,6 +950,11 @@ const nodeStatsResponseJVMProcess = `
         "inet[/127.0.0.1:9300]",
         "NONE"
       ],
+      "roles": [
+        "master",
+        "data",
+        "ingest"
+      ],
       "attributes": {
         "master": "true"
       },