package main import ( "strings" "github.com/spf13/viper" "go.uber.org/zap" "go.uber.org/zap/zapcore" ) const ( formatJSON = "json" formatConsole = "console" defaultSamplingInitial = 100 defaultSamplingThereafter = 100 ) func safeLevel(lvl string) zap.AtomicLevel { switch strings.ToLower(lvl) { case "debug": return zap.NewAtomicLevelAt(zap.DebugLevel) case "warn": return zap.NewAtomicLevelAt(zap.WarnLevel) case "error": return zap.NewAtomicLevelAt(zap.ErrorLevel) case "fatal": return zap.NewAtomicLevelAt(zap.FatalLevel) case "panic": return zap.NewAtomicLevelAt(zap.PanicLevel) default: return zap.NewAtomicLevelAt(zap.InfoLevel) } } func newLogger(v *viper.Viper) (*zap.Logger, error) { c := zap.NewProductionConfig() c.OutputPaths = []string{"stdout"} c.ErrorOutputPaths = []string{"stdout"} if v.IsSet("logger.sampling") { c.Sampling = &zap.SamplingConfig{ Initial: defaultSamplingInitial, Thereafter: defaultSamplingThereafter, } if val := v.GetInt("logger.sampling.initial"); val > 0 { c.Sampling.Initial = val } if val := v.GetInt("logger.sampling.thereafter"); val > 0 { c.Sampling.Thereafter = val } } // logger level c.Level = safeLevel(v.GetString("logger.level")) traceLvl := safeLevel(v.GetString("logger.trace_level")) // logger format switch f := v.GetString("logger.format"); strings.ToLower(f) { case formatConsole: c.Encoding = formatConsole default: c.Encoding = formatJSON } // logger time c.EncoderConfig.EncodeTime = zapcore.ISO8601TimeEncoder l, err := c.Build( // enable trace only for current log-level zap.AddStacktrace(traceLvl)) if err != nil { return nil, err } if v.GetBool("logger.no_disclaimer") { return l, nil } name := v.GetString("app.name") version := v.GetString("app.version") return l.With( zap.String("app_name", name), zap.String("app_version", version)), nil }