Add health status mapping from string to int in elasticsearch input (#3551)

plugins/inputs/elasticsearch/README.md

@@ -46,6 +46,17 @@ or [cluster-stats](https://www.elastic.co/guide/en/elasticsearch/reference/curre
   # insecure_skip_verify = false
 ```
 
+### Status mappings
+
+When reporting health (green/yellow/red), additional field `status_code`
+is reported. Field contains mapping from status:string to status_code:int
+with following rules:
+
+* `green` - 1
+* `yellow` - 2
+* `red` - 3
+* `unknown` - 0
+
 ### Measurements & Fields:
 
 field data circuit breaker measurement names:

plugins/inputs/elasticsearch/elasticsearch.go

@@ -143,6 +143,19 @@ func NewElasticsearch() *Elasticsearch {
 	}
 }
 
+// perform status mapping
+func mapHealthStatusToCode(s string) int {
+	switch strings.ToLower(s) {
+	case "green":
+		return 1
+	case "yellow":
+		return 2
+	case "red":
+		return 3
+	}
+	return 0
+}
+
 // SampleConfig returns sample configuration for this plugin.
 func (e *Elasticsearch) SampleConfig() string {
 	return sampleConfig
@@ -311,6 +324,7 @@ func (e *Elasticsearch) gatherClusterHealth(url string, acc telegraf.Accumulator
 	measurementTime := time.Now()
 	clusterFields := map[string]interface{}{
 		"status":                healthStats.Status,
+		"status_code":           mapHealthStatusToCode(healthStats.Status),
 		"timed_out":             healthStats.TimedOut,
 		"number_of_nodes":       healthStats.NumberOfNodes,
 		"number_of_data_nodes":  healthStats.NumberOfDataNodes,
@@ -330,6 +344,7 @@ func (e *Elasticsearch) gatherClusterHealth(url string, acc telegraf.Accumulator
 	for name, health := range healthStats.Indices {
 		indexFields := map[string]interface{}{
 			"status":                health.Status,
+			"status_code":           mapHealthStatusToCode(health.Status),
 			"number_of_shards":      health.NumberOfShards,
 			"number_of_replicas":    health.NumberOfReplicas,
 			"active_primary_shards": health.ActivePrimaryShards,

plugins/inputs/elasticsearch/testdata_test.go

@@ -54,6 +54,7 @@ const clusterHealthResponseWithIndices = `
 
 var clusterHealthExpected = map[string]interface{}{
 	"status":                "green",
+	"status_code":           1,
 	"timed_out":             false,
 	"number_of_nodes":       3,
 	"number_of_data_nodes":  3,
@@ -66,6 +67,7 @@ var clusterHealthExpected = map[string]interface{}{
 
 var v1IndexExpected = map[string]interface{}{
 	"status":                "green",
+	"status_code":           1,
 	"number_of_shards":      10,
 	"number_of_replicas":    1,
 	"active_primary_shards": 10,
@@ -77,6 +79,7 @@ var v1IndexExpected = map[string]interface{}{
 
 var v2IndexExpected = map[string]interface{}{
 	"status":                "red",
+	"status_code":           3,
 	"number_of_shards":      10,
 	"number_of_replicas":    1,
 	"active_primary_shards": 0,