[#373] metrics: Add FSTree metrics

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

pkg/local_object_storage/metrics/fstree.go

@@ -0,0 +1,61 @@
+package metrics
+
+import (
+	"time"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor/fstree"
+	metrics_impl "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/metrics"
+)
+
+func NewFSTreeMetricsWithoutShardID(path string, m metrics_impl.FSTreeMetrics) fstree.Metrics {
+	return &fstreeMetrics{
+		shardID: undefined,
+		path:    path,
+		m:       m,
+	}
+}
+
+type fstreeMetrics struct {
+	shardID string
+	path    string
+	m       metrics_impl.FSTreeMetrics
+}
+
+func (m *fstreeMetrics) SetParentID(parentID string) {
+	m.shardID = parentID
+}
+
+func (m *fstreeMetrics) SetMode(readOnly bool) {
+	m.m.SetMode(m.shardID, m.path, readOnly)
+}
+func (m *fstreeMetrics) Close() {
+	m.m.Close(m.shardID, m.path)
+}
+
+func (m *fstreeMetrics) Iterate(d time.Duration, success bool) {
+	m.m.MethodDuration(m.shardID, m.path, "Iterate", d, success)
+}
+func (m *fstreeMetrics) Delete(d time.Duration, success bool) {
+	m.m.MethodDuration(m.shardID, m.path, "Delete", d, success)
+}
+func (m *fstreeMetrics) Exists(d time.Duration, success bool) {
+	m.m.MethodDuration(m.shardID, m.path, "Exists", d, success)
+}
+func (m *fstreeMetrics) Put(d time.Duration, size int, success bool) {
+	m.m.MethodDuration(m.shardID, m.path, "Put", d, success)
+	if success {
+		m.m.AddPut(m.shardID, m.path, size)
+	}
+}
+func (m *fstreeMetrics) Get(d time.Duration, size int, success bool) {
+	m.m.MethodDuration(m.shardID, m.path, "Get", d, success)
+	if success {
+		m.m.AddGet(m.shardID, m.path, size)
+	}
+}
+func (m *fstreeMetrics) GetRange(d time.Duration, size int, success bool) {
+	m.m.MethodDuration(m.shardID, m.path, "GetRange", d, success)
+	if success {
+		m.m.AddGet(m.shardID, m.path, size)
+	}
+}