config.go

package zap_logger

import (
	"gopkg.in/natefinch/lumberjack.v2"
	"io"
	"time"

	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
)

type Config struct {
	// Level is the minimum enabled logging level. Note that this is a dynamic
	// level, so calling Config.Level.SetLevel will atomically change the log
	// level of all loggers descended from this config.
	Level zap.AtomicLevel
	// Development puts the logger in development mode, which changes the
	// behavior of DPanicLevel and takes stack traces more liberally.
	Development bool
	// EncoderConfig sets options for the chosen encoder. See
	// zapcore.EncoderConfig for details.
	EncoderConfig zapcore.EncoderConfig
	// DisableCaller stops annotating logs with the calling function's file
	// name and line number. By default, all logs are annotated.
	DisableCaller bool
	// Encoding sets the logger's encoding. Valid values are "json" and
	// "console" and "all", as well as any third-party encodings registered via
	// RegisterEncoder.
	Encoding string
	// MaxSize is the maximum size in megabytes of the log file before it gets
	// rotated. It defaults to 100 megabytes.
	MaxSize int
	// MaxBackups is the maximum number of old log files to retain.  The default
	// is to retain all old log files (though MaxAge may still cause them to get
	// deleted.)
	MaxBackups int
	// LocalTime determines if the time used for formatting the timestamps in
	// backup files is the computer's local time.  The default is to use UTC
	// time.
	LocalTime bool

	// Compress determines if the rotated log files should be compressed
	// using gzip. The default is not to perform compression.
	Compress bool

	// Filename is the file to write logs to.  Backup log files will be retained
	// in the same directory.  It uses <processname>-lumberjack.log in
	// os.TempDir() if empty.
	Filename string

	// MaxAge is the maximum number of days to retain old log files based on the
	// timestamp encoded in their filename.  Note that a day is defined as 24
	// hours and may not exactly correspond to calendar days due to daylight
	// savings, leap seconds, etc. The default is not to remove old log files
	// based on age.
	MaxAge int

	Interval time.Duration
}

// NewProductionEncoderConfig returns an opinionated EncoderConfig for
// production environments.
func NewProductionEncoderConfig() zapcore.EncoderConfig {
	return zapcore.EncoderConfig{
		TimeKey:        "ts",
		LevelKey:       "level",
		NameKey:        "logger",
		CallerKey:      "caller",
		FunctionKey:    zapcore.OmitKey,
		MessageKey:     "msg",
		StacktraceKey:  "stacktrace",
		LineEnding:     zapcore.DefaultLineEnding,
		EncodeLevel:    zapcore.LowercaseLevelEncoder,
		EncodeTime:     zapcore.EpochTimeEncoder,
		EncodeDuration: zapcore.SecondsDurationEncoder,
		EncodeCaller:   zapcore.ShortCallerEncoder,
	}
}

// NewProductionConfig is a reasonable production logging configuration.
// Logging is enabled at InfoLevel and above.
//
// It uses a JSON encoder, writes to standard error, and enables sampling.
// Stack traces are automatically included on logs of ErrorLevel and above.
func NewProductionConfig() Config {
	return Config{
		Level:         zap.NewAtomicLevelAt(zap.InfoLevel),
		Development:   false,
		Encoding:      "json",
		EncoderConfig: NewProductionEncoderConfig(),
		MaxSize:       100, // 100MB
		MaxBackups:    3,
		LocalTime:     true,
		Compress:      true,
		Filename:      "app.log",
		MaxAge:        30,
		Interval:      time.Duration(15) * time.Microsecond,
	}
}

// NewDevelopmentEncoderConfig returns an opinionated EncoderConfig for
// development environments.
func NewDevelopmentEncoderConfig() zapcore.EncoderConfig {
	return zapcore.EncoderConfig{
		// Keys can be anything except the empty string.
		TimeKey:        "T",
		LevelKey:       "L",
		NameKey:        "N",
		CallerKey:      "C",
		FunctionKey:    zapcore.OmitKey,
		MessageKey:     "M",
		StacktraceKey:  "S",
		LineEnding:     zapcore.DefaultLineEnding,
		EncodeLevel:    zapcore.CapitalLevelEncoder,
		EncodeTime:     zapcore.ISO8601TimeEncoder,
		EncodeDuration: zapcore.StringDurationEncoder,
		EncodeCaller:   zapcore.ShortCallerEncoder,
	}
}

// NewDevelopmentConfig is a reasonable development logging configuration.
// Logging is enabled at DebugLevel and above.
//
// It enables development mode (which makes DPanicLevel logs panic), uses a
// console encoder, writes to standard error, and disables sampling.
// Stack traces are automatically included on logs of WarnLevel and above.
func NewDevelopmentConfig() Config {
	return Config{
		Level:         zap.NewAtomicLevelAt(zap.DebugLevel),
		Development:   true,
		Encoding:      "console",
		EncoderConfig: NewDevelopmentEncoderConfig(),
		MaxSize:       10, // 10MB
		MaxBackups:    1,
		LocalTime:     false,
		Compress:      false,
		Filename:      "app.log",
		MaxAge:        30,
		Interval:      time.Duration(5) * time.Microsecond,
	}
}

func (c Config) writer() (io.Writer, *lumberjack.Logger) {
	return newWriter(c.Filename, c.MaxAge, c.MaxSize, c.MaxBackups, c.LocalTime, c.Interval)
}