Fix to avro reader

internal/memorystore/avroCheckpoint.go

@@ -28,6 +28,52 @@ var NumAvroWorkers int = 4
 
 var ErrNoNewData error = errors.New("no data in the pool")
 
+func UpdateAvroFile(f *os.File, insertCount int64) error {
+	filePath := f.Name()
+	f.Close() // close the original handle immediately
+
+	// Reopen fresh for reading
+	readFile, err := os.Open(filePath)
+	if err != nil {
+		return fmt.Errorf("failed to reopen file for reading: %v", err)
+	}
+	defer readFile.Close()
+
+	reader, err := goavro.NewOCFReader(readFile)
+	if err != nil {
+		return fmt.Errorf("failed to create OCF reader: %v", err)
+	}
+
+	codec := reader.Codec()
+
+	// Now reopen again for appending
+	appendFile, err := os.OpenFile(filePath, os.O_RDWR|os.O_APPEND, 0o644)
+	if err != nil {
+		return fmt.Errorf("failed to reopen file for appending: %v", err)
+	}
+	defer appendFile.Close()
+
+	recordList := make([]map[string]any, insertCount)
+	for i := range recordList {
+		recordList[i] = make(map[string]any)
+	}
+
+	writer, err := goavro.NewOCFWriter(goavro.OCFConfig{
+		W:               appendFile,
+		Codec:           codec,
+		CompressionName: goavro.CompressionDeflateLabel,
+	})
+	if err != nil {
+		return fmt.Errorf("failed to create OCF writer: %v", err)
+	}
+
+	if err := writer.Append(recordList); err != nil {
+		return fmt.Errorf("failed to append record: %v", err)
+	}
+
+	return nil
+}
+
 func (as *AvroStore) ToCheckpoint(dir string, dumpAll bool) (int, error) {
 	levels := make([]*AvroLevel, 0)
 	selectors := make([][]string, 0)