insight support terms top by sorted sub metric

model/insight/metric_data.go

@@ -16,6 +16,7 @@ type Metric struct {
 	BucketSize   string `json:"bucket_size,omitempty"`
 	Filter interface{}      `json:"filter,omitempty"`
 	Groups []MetricGroupItem `json:"groups,omitempty"` //bucket group
+	Sort []GroupSort `json:"sort,omitempty"`
 	ClusterId string   `json:"cluster_id,omitempty"`
 	Formula string `json:"formula,omitempty"`
 	Items []MetricItem `json:"items"`
@@ -25,6 +26,11 @@ type Metric struct {
 	BucketLabel *BucketLabel `json:"bucket_label,omitempty"`
 }
 
+type GroupSort struct {
+	Key string `json:"key"`
+	Direction string `json:"direction"`
+}
+
 type MetricGroupItem struct {
 	Field string `json:"field"`
 	Limit int `json:"limit"`

plugin/api/insight/metric_util.go

@@ -125,11 +125,19 @@ func GenerateQuery(metric *insight.Metric) (interface{}, error) {
 			if limit <= 0 {
 				limit = 10
 			}
+			termsCfg := util.MapStr{
+				"field": groups[i].Field,
+				"size":  limit,
+			}
+			if i == grpLength - 1 && len(metric.Sort) > 0 {
+				var termsOrder []interface{}
+				for _, sortItem := range metric.Sort {
+					termsOrder = append(termsOrder, util.MapStr{sortItem.Key: sortItem.Direction})
+				}
+				termsCfg["order"] = termsOrder
+			}
 			groupAgg := util.MapStr{
-				"terms": util.MapStr{
-					"field": groups[i].Field,
-					"size":  limit,
-				},
+				"terms": termsCfg,
 			}
 			groupID := util.GetUUID()
 			if lastGroupAgg != nil {