usage model (#128)

controller/metrics/model.go

@@ -1,5 +1,34 @@
 package metrics
 
+import (
+	"fmt"
+	"github.com/openziti/zrok/util"
+	"time"
+)
+
+type Usage struct {
+	ProcessedStamp time.Time
+	IntervalStart  time.Time
+	ZitiServiceId  string
+	ZitiCircuitId  string
+	FrontendTx     int64
+	FrontendRx     int64
+	BackendTx      int64
+	BackendRx      int64
+}
+
+func (u Usage) String() string {
+	out := "Usage {"
+	out += fmt.Sprintf("processed '%v'", u.ProcessedStamp)
+	out += ", " + fmt.Sprintf("interval '%v'", u.IntervalStart)
+	out += ", " + fmt.Sprintf("service '%v'", u.ZitiServiceId)
+	out += ", " + fmt.Sprintf("circuit '%v'", u.ZitiCircuitId)
+	out += ", " + fmt.Sprintf("fe {rx %v, tx %v}", util.BytesToSize(u.FrontendRx), util.BytesToSize(u.FrontendTx))
+	out += ", " + fmt.Sprintf("be {rx %v, tx %v}", util.BytesToSize(u.BackendRx), util.BytesToSize(u.BackendTx))
+	out += "}"
+	return out
+}
+
 type Source interface {
 	Start(chan map[string]interface{}) (chan struct{}, error)
 	Stop()