package middleware import ( "bytes" "encoding/json" "io" "strconv" "strings" "sync" "time" "github.com/labstack/echo/v4" "github.com/labstack/gommon/color" "github.com/valyala/fasttemplate" ) type ( // LoggerConfig defines the config for Logger middleware. LoggerConfig struct { // Skipper defines a function to skip middleware. Skipper Skipper // Tags to construct the logger format. // // - time_unix // - time_unix_nano // - time_rfc3339 // - time_rfc3339_nano // - time_custom // - id (Request ID) // - remote_ip // - uri // - host // - method // - path // - protocol // - referer // - user_agent // - status // - error // - latency (In nanoseconds) // - latency_human (Human readable) // - bytes_in (Bytes received) // - bytes_out (Bytes sent) // - header:<NAME> // - query:<NAME> // - form:<NAME> // // Example "${remote_ip} ${status}" // // Optional. Default value DefaultLoggerConfig.Format. Format string `yaml:"format"` // Optional. Default value DefaultLoggerConfig.CustomTimeFormat. CustomTimeFormat string `yaml:"custom_time_format"` // Output is a writer where logs in JSON format are written. // Optional. Default value os.Stdout. Output io.Writer template *fasttemplate.Template colorer *color.Color pool *sync.Pool } ) var ( // DefaultLoggerConfig is the default Logger middleware config. DefaultLoggerConfig = LoggerConfig{ Skipper: DefaultSkipper, Format: `{"time":"${time_rfc3339_nano}","id":"${id}","remote_ip":"${remote_ip}",` + `"host":"${host}","method":"${method}","uri":"${uri}","user_agent":"${user_agent}",` + `"status":${status},"error":"${error}","latency":${latency},"latency_human":"${latency_human}"` + `,"bytes_in":${bytes_in},"bytes_out":${bytes_out}}` + "\n", CustomTimeFormat: "2006-01-02 15:04:05.00000", colorer: color.New(), } ) // Logger returns a middleware that logs HTTP requests. func Logger() echo.MiddlewareFunc { return LoggerWithConfig(DefaultLoggerConfig) } // LoggerWithConfig returns a Logger middleware with config. // See: `Logger()`. func LoggerWithConfig(config LoggerConfig) echo.MiddlewareFunc { // Defaults if config.Skipper == nil { config.Skipper = DefaultLoggerConfig.Skipper } if config.Format == "" { config.Format = DefaultLoggerConfig.Format } if config.Output == nil { config.Output = DefaultLoggerConfig.Output } config.template = fasttemplate.New(config.Format, "${", "}") config.colorer = color.New() config.colorer.SetOutput(config.Output) config.pool = &sync.Pool{ New: func() interface{} { return bytes.NewBuffer(make([]byte, 256)) }, } return func(next echo.HandlerFunc) echo.HandlerFunc { return func(c echo.Context) (err error) { if config.Skipper(c) { return next(c) } req := c.Request() res := c.Response() start := time.Now() if err = next(c); err != nil { c.Error(err) } stop := time.Now() buf := config.pool.Get().(*bytes.Buffer) buf.Reset() defer config.pool.Put(buf) if _, err = config.template.ExecuteFunc(buf, func(w io.Writer, tag string) (int, error) { switch tag { case "time_unix": return buf.WriteString(strconv.FormatInt(time.Now().Unix(), 10)) case "time_unix_nano": return buf.WriteString(strconv.FormatInt(time.Now().UnixNano(), 10)) case "time_rfc3339": return buf.WriteString(time.Now().Format(time.RFC3339)) case "time_rfc3339_nano": return buf.WriteString(time.Now().Format(time.RFC3339Nano)) case "time_custom": return buf.WriteString(time.Now().Format(config.CustomTimeFormat)) case "id": id := req.Header.Get(echo.HeaderXRequestID) if id == "" { id = res.Header().Get(echo.HeaderXRequestID) } return buf.WriteString(id) case "remote_ip": return buf.WriteString(c.RealIP()) case "host": return buf.WriteString(req.Host) case "uri": return buf.WriteString(req.RequestURI) case "method": return buf.WriteString(req.Method) case "path": p := req.URL.Path if p == "" { p = "/" } return buf.WriteString(p) case "protocol": return buf.WriteString(req.Proto) case "referer": return buf.WriteString(req.Referer()) case "user_agent": return buf.WriteString(req.UserAgent()) case "status": n := res.Status s := config.colorer.Green(n) switch { case n >= 500: s = config.colorer.Red(n) case n >= 400: s = config.colorer.Yellow(n) case n >= 300: s = config.colorer.Cyan(n) } return buf.WriteString(s) case "error": if err != nil { // Error may contain invalid JSON e.g. `"` b, _ := json.Marshal(err.Error()) b = b[1 : len(b)-1] return buf.Write(b) } case "latency": l := stop.Sub(start) return buf.WriteString(strconv.FormatInt(int64(l), 10)) case "latency_human": return buf.WriteString(stop.Sub(start).String()) case "bytes_in": cl := req.Header.Get(echo.HeaderContentLength) if cl == "" { cl = "0" } return buf.WriteString(cl) case "bytes_out": return buf.WriteString(strconv.FormatInt(res.Size, 10)) default: switch { case strings.HasPrefix(tag, "header:"): return buf.Write([]byte(c.Request().Header.Get(tag[7:]))) case strings.HasPrefix(tag, "query:"): return buf.Write([]byte(c.QueryParam(tag[6:]))) case strings.HasPrefix(tag, "form:"): return buf.Write([]byte(c.FormValue(tag[5:]))) case strings.HasPrefix(tag, "cookie:"): cookie, err := c.Cookie(tag[7:]) if err == nil { return buf.Write([]byte(cookie.Value)) } } } return 0, nil }); err != nil { return } if config.Output == nil { _, err = c.Logger().Output().Write(buf.Bytes()) return } _, err = config.Output.Write(buf.Bytes()) return } } }