[#661] metrcis: Add rebuild percent metric

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/metrics/blobovnicza.go

@@ -25,6 +25,7 @@ type BlobobvnizcaMetrics interface {
 	DecOpenBlobovniczaCount(shardID, path string)
 
 	BlobovniczaTreeRebuildStatus(shardID, path, status string)
+	BlobovniczaTreeRebuildPercent(shardID, path string, value uint32)
 	BlobovniczaTreeObjectMoved(shardID, path string, d time.Duration)
 }
 
@@ -38,6 +39,7 @@ type blobovnicza struct {
 	treeOpenCounter        *prometheus.GaugeVec
 	treeObjectMoveDuration *prometheus.HistogramVec
 	treeRebuildStatus      *shardIDPathModeValue
+	treeRebuildPercent     *prometheus.GaugeVec
 }
 
 func newBlobovnicza() *blobovnicza {
@@ -87,6 +89,12 @@ func newBlobovnicza() *blobovnicza {
 			Help:      "Accumulated Blobovnicza tree object move duration",
 		}, []string{shardIDLabel, pathLabel}),
 		treeRebuildStatus: newShardIDPathMode(blobovniczaTreeSubSystem, "rebuild_status", "Blobovnicza tree rebuild status"),
+		treeRebuildPercent: metrics.NewGaugeVec(prometheus.GaugeOpts{
+			Namespace: namespace,
+			Subsystem: blobovniczaTreeSubSystem,
+			Name:      "rebuild_complete_percent",
+			Help:      "Percent of rebuild completeness",
+		}, []string{shardIDLabel, pathLabel}),
 	}
 }
 
@@ -112,6 +120,10 @@ func (b *blobovnicza) CloseBlobobvnizcaTree(shardID, path string) {
 		shardIDLabel: shardID,
 		pathLabel:    path,
 	})
+	b.treeRebuildPercent.DeletePartialMatch(prometheus.Labels{
+		shardIDLabel: shardID,
+		pathLabel:    path,
+	})
 	b.treeRebuildStatus.SetMode(shardID, path, undefinedStatus)
 }
 
@@ -191,3 +203,10 @@ func (b *blobovnicza) BlobovniczaTreeObjectMoved(shardID, path string, d time.Du
 		pathLabel:    path,
 	}).Observe(d.Seconds())
 }
+
+func (b *blobovnicza) BlobovniczaTreeRebuildPercent(shardID, path string, value uint32) {
+	b.treeRebuildPercent.With(prometheus.Labels{
+		shardIDLabel: shardID,
+		pathLabel:    path,
+	}).Set(float64(value))
+}