o2logger: flush buffer on cleanup

go/pkg/log/log.go

@@ -35,7 +35,14 @@ func NewHandler(cfg *config.Config) (slog.Handler, func() error) {
 	}
 
 	if cfg.Bool("telemetry.openobserve.enable") && cfg.Bool("telemetry.openobserve.log.enable") {
-		handlers = append(handlers, createO2Logger(cfg))
+		log, clean := createO2Logger(cfg)
+		cl := cleanup
+		handlers = append(handlers, log)
+		cleanup = func() error {
+			err := cl()
+			clean()
+			return err
+		}
 	}
 
 	if len(handlers) == 0 {
@@ -88,14 +95,14 @@ func createStandardLogger(cfg *config.Config) (slog.Handler, func() error) {
 	}
 }
 
-func createO2Logger(cfg *config.Config) slog.Handler {
+func createO2Logger(cfg *config.Config) (slog.Handler, func()) {
 	var lvl slog.Level
 	_ = lvl.UnmarshalText(cfg.Bytes("telemetry.openobserve.log.level"))
 	opts := &slog.HandlerOptions{
 		AddSource: cfg.Bool("telemetry.openobserve.log.source"),
 		Level:     lvl,
 	}
-	return telemetry.NewOpenObserveHandler(telemetry.OpenObserveHandlerOptions{
+	handler := telemetry.NewOpenObserveHandler(telemetry.OpenObserveHandlerOptions{
 		HandlerOptions: opts,
 		BufferSize:     cfg.Int("telemetry.openobserve.log.buffer.size"),
 		BufferTimeout:  cfg.Duration("telemetry.openobserve.log.buffer.timeout"),
@@ -105,4 +112,5 @@ func createO2Logger(cfg *config.Config) slog.Handler {
 		Username:       cfg.String("telemetry.openobserve.log.username"),
 		Password:       cfg.String("telemetry.openobserve.log.password"),
 	})
+	return handler, handler.Flush
 }

go/pkg/telemetry/open_observe.go

@@ -47,22 +47,7 @@ func (sl *OpenObserveHandler) Handle(ctx context.Context, record slog.Record) er
 			sl.mu.Lock()
 			defer sl.mu.Unlock()
 			sl.sendDebounceFunc = nil
-			if sl.buffer.Len() < 1 {
-				return
-			}
-			b := sl.extractBuffer().Bytes()
-			if b[len(b)-1] == ',' {
-				b = b[:len(b)-1]
-			}
-			if b[len(b)-1] == '\n' {
-				b = b[:len(b)-1]
-			}
-			b = append(b, ']')
-			sl.semaphore <- struct{}{}
-			go func() {
-				defer func() { <-sl.semaphore }()
-				sl.postLog(bytes.NewReader(b))
-			}()
+			sl.flushAsync()
 		})
 	}
 
@@ -92,6 +77,42 @@ func (sl *OpenObserveHandler) Handle(ctx context.Context, record slog.Record) er
 	return nil
 }
 
+func (sl *OpenObserveHandler) Flush() {
+	sl.mu.Lock()
+	defer sl.mu.Unlock()
+	if sl.buffer.Len() < 1 {
+		return
+	}
+	b := sl.extractBuffer().Bytes()
+	if b[len(b)-1] == ',' {
+		b = b[:len(b)-1]
+	}
+	if b[len(b)-1] == '\n' {
+		b = b[:len(b)-1]
+	}
+	b = append(b, ']')
+	sl.postLog(bytes.NewReader(b))
+}
+
+func (sl *OpenObserveHandler) flushAsync() {
+	if sl.buffer.Len() < 1 {
+		return
+	}
+	b := sl.extractBuffer().Bytes()
+	if b[len(b)-1] == ',' {
+		b = b[:len(b)-1]
+	}
+	if b[len(b)-1] == '\n' {
+		b = b[:len(b)-1]
+	}
+	b = append(b, ']')
+	sl.semaphore <- struct{}{}
+	go func() {
+		defer func() { <-sl.semaphore }()
+		sl.postLog(bytes.NewReader(b))
+	}()
+}
+
 func (sl *OpenObserveHandler) extractBuffer() *bytes.Buffer {
 	b := sl.buffer.Bytes()
 	newb := make([]byte, len(b))