Fix missing err handling

Author: davissp14

cmd/etcd-backup/backup.go

@@ -36,7 +36,9 @@ func runBackups(ctx context.Context) {
 		log.Printf("[error] Failed to initialize etcd client: %v", err)
 		panic(err)
 	}
-	defer cli.Client.Close()
+	defer func() {
+		_ = cli.Client.Close()
+	}()
 
 	s3Client, err := flyetcd.NewS3Client(ctx, s3Prefix)
 	if err != nil {
@@ -121,7 +123,11 @@ func performBackup(parentCtx context.Context, cli *flyetcd.Client, s3Client *fly
 	if err != nil {
 		return fmt.Errorf("failed to create temp dir: %w", err)
 	}
-	defer os.RemoveAll(tmpDir)
+	defer func() {
+		if err := os.RemoveAll(tmpDir); err != nil {
+			log.Printf("Error removing temporary directory: %v", err)
+		}
+	}()
 
 	fileName := fmt.Sprintf("backup-%s.db", time.Now().Format("20060102-150405"))
 	backupPath := filepath.Join(tmpDir, fileName)
@@ -156,7 +162,9 @@ func updateLastBackupTime(t time.Time) error {
 	if err != nil {
 		return fmt.Errorf("failed to open backup log: %v", err)
 	}
-	defer backupLog.Close()
+	defer func() {
+		_ = backupLog.Close()
+	}()
 
 	if _, err := fmt.Fprintf(backupLog, "%s\n", t.Format(time.RFC3339)); err != nil {
 		return fmt.Errorf("failed to write backup time: %v", err)
@@ -175,7 +183,9 @@ func lastBackupTime() (time.Time, error) {
 	if err != nil {
 		return time.Time{}, fmt.Errorf("failed to open backup log: %w", err)
 	}
-	defer backupLog.Close()
+	defer func() {
+		_ = backupLog.Close()
+	}()
 
 	var timeStr string
 	if _, err := fmt.Fscanln(backupLog, &timeStr); err != nil {

cmd/etcd-backup/metrics.go

@@ -119,7 +119,9 @@ func metricsHandler() http.Handler {
 		}
 
 		// Add a newline separator
-		w.Write([]byte("\n"))
+		if _, err := w.Write([]byte("\n")); err != nil {
+			log.Printf("Error writing newline: %v", err)
+		}
 
 		// Then fetch and write etcd metrics
 		client := http.Client{
@@ -131,7 +133,9 @@ func metricsHandler() http.Handler {
 			scrapeErrors.Inc()
 			return
 		}
-		defer resp.Body.Close()
+		defer func() {
+			_ = resp.Body.Close()
+		}()
 
 		_, err = io.Copy(w, resp.Body)
 		if err != nil {

internal/flyetcd/client.go

@@ -75,7 +75,9 @@ func (c *Client) Backup(ctx context.Context, backupPath string) (int64, error) {
 	if err != nil {
 		return 0, fmt.Errorf("failed to create snapshot: %v", err)
 	}
-	defer snapReader.Close()
+	defer func() {
+		_ = snapReader.Close()
+	}()
 
 	backupFile, err := os.Create(backupPath)
 	if err != nil {
@@ -116,7 +118,9 @@ func (c *Client) Restore(ctx context.Context, snapshotPath string) error {
 	if err != nil {
 		return fmt.Errorf("failed to open backup file: %v", err)
 	}
-	defer snapFile.Close()
+	defer func() {
+		_ = snapFile.Close()
+	}()
 
 	cmd := exec.Command("etcdctl", "snapshot", "restore", snapshotPath,
 		"--data-dir", node.Config.DataDir,

internal/flyetcd/s3.go

@@ -56,7 +56,9 @@ func (s *S3Client) Upload(ctx context.Context, backupPath string) (string, error
 	if err != nil {
 		return "", fmt.Errorf("failed to open backup file: %w", err)
 	}
-	defer file.Close()
+	defer func() {
+		_ = file.Close()
+	}()
 
 	resp, err := s.Client.PutObject(ctx, &s3.PutObjectInput{
 		Bucket: aws.String(s.bucket),
@@ -77,7 +79,9 @@ func (s *S3Client) Download(ctx context.Context, directory, version string) (str
 	if err != nil {
 		return "", fmt.Errorf("failed to create snapshot file: %v", err)
 	}
-	defer file.Close()
+	defer func() {
+		_ = file.Close()
+	}()
 
 	s3Key := filepath.Join(s.prefix, S3BackupName)
 	input := &s3.GetObjectInput{
@@ -90,7 +94,9 @@ func (s *S3Client) Download(ctx context.Context, directory, version string) (str
 	if err != nil {
 		return "", fmt.Errorf("failed to download from S3: %v", err)
 	}
-	defer result.Body.Close()
+	defer func() {
+		_ = result.Body.Close()
+	}()
 
 	if _, err := io.Copy(file, result.Body); err != nil {
 		return "", fmt.Errorf("failed to write snapshot: %v", err)