package exporter import ( "encoding/json" "fmt" "os" "sync" ) // JSONExporter exports response data as JSON streaming file type JSONExporter struct { Filename string EscapeHTML bool file *os.File once sync.Once } // Export exports response data as JSON streaming file func (e JSONExporter) Export(exports chan interface{}) { // Default Filename if e.Filename == "" { e.Filename = "out.json" } // Create File e.once.Do(func() { newFile, err := os.OpenFile(e.Filename, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666) if err != nil { fmt.Fprintf(os.Stderr, "output file creation error: %v", err) return } e.file = newFile }) // Export data as responses came for res := range exports { encoder := json.NewEncoder(e.file) encoder.SetEscapeHTML(e.EscapeHTML) encoder.Encode(res) } }