From c03bd3e3a2e3a167ed4ffbcac2b268c545c96065 Mon Sep 17 00:00:00 2001
From: Andrej Mickov <andrej@ferdzo.xyz>
Date: Mon, 2 Mar 2026 23:26:57 +0100
Subject: [PATCH] Minimal fixes for metrics

---
 api/api.go              |  3 +--
 metrics/metrics.go      |  2 +-
 metrics/metrics_test.go |  8 ++++++++
 service/service.go      | 15 +++++++++------
 storage/blob.go         |  4 +++-
 5 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/api/api.go b/api/api.go
index 250bac2..69ccfa9 100644
--- a/api/api.go
+++ b/api/api.go
@@ -661,13 +661,12 @@ func (l *limitedListener) Accept() (net.Conn, error) {
 		l.slots <- struct{}{}
 		metrics.Default.DecRequestQueueLength()
 	}
-	metrics.Default.IncConnectionPoolActive()
 	conn, err := l.Listener.Accept()
 	if err != nil {
 		<-l.slots
-		metrics.Default.DecConnectionPoolActive()
 		return nil, err
 	}
+	metrics.Default.IncConnectionPoolActive()
 	return &limitedConn{
 		Conn: conn,
 		done: func() {
diff --git a/metrics/metrics.go b/metrics/metrics.go
index 8f11b39..45115df 100644
--- a/metrics/metrics.go
+++ b/metrics/metrics.go
@@ -762,7 +762,7 @@ func trimFloat(v float64) string {
 }
 
 func escapeLabelValue(value string) string {
-	value = strings.ReplaceAll(value, `\\`, `\\\\`)
+	value = strings.ReplaceAll(value, `\`, `\\`)
 	value = strings.ReplaceAll(value, "\n", `\\n`)
 	value = strings.ReplaceAll(value, `"`, `\\"`)
 	return value
diff --git a/metrics/metrics_test.go b/metrics/metrics_test.go
index 2fffc4f..2f25c23 100644
--- a/metrics/metrics_test.go
+++ b/metrics/metrics_test.go
@@ -24,3 +24,11 @@ func TestRenderPrometheusHistogramNoEmptyLabelSet(t *testing.T) {
 		t.Fatalf("unexpected empty label set for gc count metric")
 	}
 }
+
+func TestEscapeLabelValueEscapesSingleBackslash(t *testing.T) {
+	got := escapeLabelValue(`a\b`)
+	want := `a\\b`
+	if got != want {
+		t.Fatalf("escapeLabelValue returned %q, want %q", got, want)
+	}
+}
diff --git a/service/service.go b/service/service.go
index f06dd66..9d7db43 100644
--- a/service/service.go
+++ b/service/service.go
@@ -106,10 +106,6 @@ func (s *ObjectService) PutObject(bucket, key, contentType string, input io.Read
 
 func (s *ObjectService) GetObject(bucket, key string) (io.ReadCloser, *models.ObjectManifest, error) {
 	start := time.Now()
-	success := false
-	defer func() {
-		metrics.Default.ObserveService("get_object", time.Since(start), success)
-	}()
 
 	waitStart := time.Now()
 	s.gcMu.RLock()
@@ -120,20 +116,27 @@ func (s *ObjectService) GetObject(bucket, key string) (io.ReadCloser, *models.Ob
 	if err != nil {
 		metrics.Default.ObserveLockHold("gc_mu_read", time.Since(holdStart))
 		s.gcMu.RUnlock()
+		metrics.Default.ObserveService("get_object", time.Since(start), false)
 		return nil, nil, err
 	}
 	pr, pw := io.Pipe()
 
 	go func() {
+		streamOK := false
+		defer func() {
+			metrics.Default.ObserveService("get_object", time.Since(start), streamOK)
+		}()
 		defer metrics.Default.ObserveLockHold("gc_mu_read", time.Since(holdStart))
 		defer s.gcMu.RUnlock()
 		if err := s.blob.AssembleStream(manifest.Chunks, pw); err != nil {
 			_ = pw.CloseWithError(err)
 			return
 		}
-		_ = pw.Close()
+		if err := pw.Close(); err != nil {
+			return
+		}
+		streamOK = true
 	}()
-	success = true
 	return pr, manifest, nil
 }
 
diff --git a/storage/blob.go b/storage/blob.go
index 41297df..667958f 100644
--- a/storage/blob.go
+++ b/storage/blob.go
@@ -88,8 +88,9 @@ func (bs *BlobStore) IngestStream(stream io.Reader) ([]string, int64, string, er
 func (bs *BlobStore) saveBlob(chunkID string, data []byte) error {
 	start := time.Now()
 	success := false
+	writtenBytes := int64(0)
 	defer func() {
-		metrics.Default.ObserveBlob("write_chunk", time.Since(start), int64(len(data)), success)
+		metrics.Default.ObserveBlob("write_chunk", time.Since(start), writtenBytes, success)
 	}()
 
 	if !isValidChunkID(chunkID) {
@@ -144,6 +145,7 @@ func (bs *BlobStore) saveBlob(chunkID string, data []byte) error {
 	if err := syncDir(dir); err != nil {
 		return err
 	}
+	writtenBytes = int64(len(data))
 	success = true
 	return nil
 }