Revel embedding zap logger

log.go

package logger


// LoggedError is wrapper to differentiate logged panics from unexpected ones.
import (
	"os"
	"fmt"
	"strings"
	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
	"sync"
	"go.uber.org/zap/buffer"
	"time"
	"encoding/base64"
	"unicode/utf8"
	"encoding/json"
	"math"

	"io"
)

type (
	MultiLogger interface {
		//log15.Logger
		//// New returns a new Logger that has this logger's context plus the given context
		New(ctx ...interface{}) MultiLogger
		//
		// The encoders job is to encode the
		SetHandler(h LogHandler)
		SetStackDepth(int) MultiLogger
		//
		//// Log a message at the given level with context key/value pairs
		Debug(msg string, ctx ...interface{})
		Debugf(msg string, params ...interface{})
		Info(msg string, ctx ...interface{})
		Infof(msg string, params ...interface{})
		Warn(msg string, ctx ...interface{})
		Warnf(msg string, params ...interface{})
		Error(msg string, ctx ...interface{})
		Errorf(msg string, params ...interface{})
		Crit(msg string, ctx ...interface{})
		Critf(msg string, params ...interface{})

		//// Logs a message as an Crit and exits
		Fatal(msg string, ctx ...interface{})
		Fatalf(msg string, params ...interface{})
		//// Logs a message as an Crit and panics
		Panic(msg string, ctx ...interface{})
		Panicf(msg string, params ...interface{})
	}

	// The log han
	LogHandler interface {
		Encode(Record) ([]byte, error)
		GetLevel() Level
		GetWriter() io.Writer
	}

	// The Record
	Record struct {
		Level      Level
		Time       time.Time
		LoggerName string
		Message    string
		Caller     EntryCaller
		Stack      string
    Context    []Field
}

	// The fields passed in
	Field interface {
		GetKey() string
		GetValueAsString() string
		GetValue() interface{}
	}

	EntryCaller interface {
		IsDefined() bool
		GetPC() uintptr
		GetFile() string
		GetLine() int
	}

	// Called only if the logger needs
	ResolveLaterLogger func() interface{}

	FieldType int
	Level int
)

type (
	zapLogger struct {
		logger *zap.SugaredLogger
		coreList []*zapcore.Core
	}
	zapField struct {
		Key       string
		Type      FieldType
		Integer   int64
		String    string
		Interface interface{}
	}
	zapEntryCaller struct {
		Defined bool
		PC      uintptr
		File    string
		Line    int
	}
	zapEncoder struct {
		lh LogHandler
	}
)

func newLogger(addCaller bool) MultiLogger {
	logger := zap.New(nil).WithOptions(zap.AddCaller())
	l := &zapLogger{logger:logger.Sugar()}

	return l
}

// It is up to the handler to determine the synchronization to the output
// streams
func (z *zapLogger) SetHandler(lh LogHandler) {
	// Swap out the logger when a new handler is attached
	encoder := &zapEncoder{lh}
	levelHandler := zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
		return  lvl >= zapcore.Level(lh.GetLevel())
	})
	logger := zap.New(zapcore.NewCore(encoder, nil, levelHandler)).WithOptions(zap.AddCaller())
	Logger.With("foo","bar").Desugar().Core()
}

var Logger *zap.SugaredLogger

func InitLogger(logLevel zapcore.Level) {
	config :=zap.NewDevelopmentEncoderConfig()
	config.EncodeLevel = zapcore.CapitalColorLevelEncoder

	consoleEncoder := NewConsoleEncoder(config)
	lowPriority := zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
		return  lvl >= logLevel
	})

	consoleDebugging := zapcore.Lock(os.Stdout)
	core := zapcore.NewTee(
		zapcore.NewCore(consoleEncoder, consoleDebugging, lowPriority),
	)
	logger := zap.New(core).WithOptions(zap.AddCaller())
	Logger = logger.Sugar()
}
type LoggedError struct{ error }

func NewLoggedError(err error) *LoggedError {
	return &LoggedError{err}
}

func Errorf(format string, args ...interface{}) {
	// Ensure the user's command prompt starts on the next line.
	if !strings.HasSuffix(format, "\n") {
		format += "\n"
	}
	fmt.Fprintf(os.Stderr, format, args...)
	panic(format) // Panic instead of os.Exit so that deferred will run.
}



// This is all for the Console logger - a little wordy but it works

var _sliceEncoderPool = sync.Pool{
	New: func() interface{} {
		return &sliceArrayEncoder{elems: make([]interface{}, 0, 2)}
	},
}

func getSliceEncoder() *sliceArrayEncoder {
	return _sliceEncoderPool.Get().(*sliceArrayEncoder)
}

func putSliceEncoder(e *sliceArrayEncoder) {
	e.elems = e.elems[:0]
	_sliceEncoderPool.Put(e)
}

type consoleEncoder struct {
	*zapcore.EncoderConfig
	openNamespaces int
	buf            *buffer.Buffer
	reflectBuf *buffer.Buffer
	reflectEnc *json.Encoder
}

var (
	_pool = buffer.NewPool()
	// Get retrieves a buffer from the pool, creating one if necessary.
	Get = _pool.Get
)


// NewConsoleEncoder creates an encoder whose output is designed for human -
// rather than machine - consumption. It serializes the core log entry data
// (message, level, timestamp, etc.) in a plain-text format and leaves the
// structured context as JSON.
//
// Note that although the console encoder doesn't use the keys specified in the
// encoder configuration, it will omit any element whose key is set to the empty
// string.
func NewConsoleEncoder(cfg zapcore.EncoderConfig) zapcore.Encoder {
	ec := &consoleEncoder{buf : Get(), reflectBuf: Get()}
	ec.EncoderConfig = &cfg
	return ec
}

func (c consoleEncoder) Clone() zapcore.Encoder {
	return &consoleEncoder{buf : Get(), reflectBuf: Get()}
}

func (c consoleEncoder) EncodeEntry(ent zapcore.Entry, fields []zapcore.Field) (*buffer.Buffer, error) {
	line := Get()

	var color = 0
	switch ent.Level {
	case zap.PanicLevel:
		// Magenta
		color = 35
	case zap.ErrorLevel:
		// Red
		color = 31
	case zap.WarnLevel:
		// Yellow
		color = 33
	case zap.InfoLevel:
		// Green
		color = 32
	case zap.DebugLevel:
		// Cyan
		color = 36
	}

	// We don't want the entry's metadata to be quoted and escaped (if it's
	// encoded as strings), which means that we can't use the JSON encoder. The
	// simplest option is to use the memory encoder and fmt.Fprint.
	//
	// If this ever becomes a performance bottleneck, we can implement
	// ArrayEncoder for our plain-text format.
	arr := getSliceEncoder()
	if c.LevelKey != "" && c.EncodeLevel != nil {
		arr.AppendString(fmt.Sprintf("\x1b[%dm%-5s\x1b[0m",color,ent.Level.CapitalString()))
	}
	if ent.LoggerName != "" && c.NameKey != "" {
		nameEncoder := c.EncodeName

		if nameEncoder == nil {
			// Fall back to FullNameEncoder for backward compatibility.
			nameEncoder = zapcore.FullNameEncoder
		}

		nameEncoder(ent.LoggerName, arr)
	}
	if c.TimeKey != "" && c.EncodeTime != nil {
		arr.AppendString(ent.Time.Format("15:04:05"))
	}

	if ent.Caller.Defined && c.CallerKey != "" && c.EncodeCaller != nil {
		c.EncodeCaller(ent.Caller, arr)
	}
	for i := range arr.elems {
		if i > 0 {
			line.AppendByte(' ')
		}
		fmt.Fprint(line, arr.elems[i])
	}
	putSliceEncoder(arr)

	// Add the message itself.
	if c.MessageKey != "" {
		c.addTabIfNecessary(line)
		line.AppendString(ent.Message)
	}

	// Add any structured context.
	 c.writeContext(line, fields)

	// If there's no stacktrace key, honor that; this allows users to force
	// single-line output.
	if ent.Stack != "" && c.StacktraceKey != "" {
		line.AppendByte('\n')
		line.AppendString(ent.Stack)
	}

	if c.LineEnding != "" {
		line.AppendString(c.LineEnding)
	} else {
		line.AppendString(zapcore.DefaultLineEnding)
	}
	return line, nil
}

func (c consoleEncoder) writeContext(line *buffer.Buffer, extra []zapcore.Field) {
	context := c.Clone().(*consoleEncoder)
	defer context.buf.Free()
	//
	addFields(context, extra)
	context.closeOpenNamespaces()
	if context.buf.Len() == 0 {
		return
	}
	//
	line.Write(context.buf.Bytes())
}
func addFields(enc zapcore.ObjectEncoder, fields []zapcore.Field) {
	for i := range fields {
		fields[i].AddTo(enc)
	}
}


func (c consoleEncoder) addTabIfNecessary(line *buffer.Buffer) {
	if line.Len() > 0 {
		line.AppendByte('\t')
	}
}


func (enc *consoleEncoder) AddArray(key string, arr zapcore.ArrayMarshaler) error {
	enc.addKey(key)
	return enc.AppendArray(arr)
}

func (enc *consoleEncoder) AddObject(key string, obj zapcore.ObjectMarshaler) error {
	enc.addKey(key)
	return enc.AppendObject(obj)
}

func (enc *consoleEncoder) AddBinary(key string, val []byte) {
	enc.AddString(key, base64.StdEncoding.EncodeToString(val))
}

func (enc *consoleEncoder) AddByteString(key string, val []byte) {
	enc.addKey(key)
	enc.AppendByteString(val)
}

func (enc *consoleEncoder) AddBool(key string, val bool) {
	enc.addKey(key)
	enc.AppendBool(val)
}

func (enc *consoleEncoder) AddComplex128(key string, val complex128) {
	enc.addKey(key)
	enc.AppendComplex128(val)
}

func (enc *consoleEncoder) AddDuration(key string, val time.Duration) {
	enc.addKey(key)
	enc.AppendDuration(val)
}

func (enc *consoleEncoder) AddFloat64(key string, val float64) {
	enc.addKey(key)
	enc.AppendFloat64(val)
}

func (enc *consoleEncoder) AddInt64(key string, val int64) {
	enc.addKey(key)
	enc.AppendInt64(val)
}

func (enc *consoleEncoder) AddReflected(key string, obj interface{}) error {
	enc.resetReflectBuf()
	err := enc.reflectEnc.Encode(obj)
	if err != nil {
		return err
	}
	enc.reflectBuf.TrimNewline()
	enc.addKey(key)
	_, err = enc.buf.Write(enc.reflectBuf.Bytes())
	return err
}

func (enc *consoleEncoder) OpenNamespace(key string) {
	enc.addKey(key)
	enc.buf.AppendByte('{')
	enc.openNamespaces++
}

func (enc *consoleEncoder) AddString(key, val string) {
	enc.addKey(key)
	enc.AppendString(val)
}

func (enc *consoleEncoder) AddTime(key string, val time.Time) {
	enc.addKey(key)
	enc.AppendTime(val)
}

func (enc *consoleEncoder) AddUint64(key string, val uint64) {
	enc.addKey(key)
	enc.AppendUint64(val)
}

func (enc *consoleEncoder) addKey(key string) {
	// Print key in different color
	enc.buf.AppendString(fmt.Sprintf(" \x1b[%dm%s\x1b[0m",36,key))

	enc.buf.AppendByte('=')
}

func (enc *consoleEncoder) AppendArray(arr zapcore.ArrayMarshaler) error {
	enc.buf.AppendByte('[')
	err := arr.MarshalLogArray(enc)
	enc.buf.AppendByte(']')
	return err
}

func (enc *consoleEncoder) AppendObject(obj zapcore.ObjectMarshaler) error {
	enc.buf.AppendByte('{')
	err := obj.MarshalLogObject(enc)
	enc.buf.AppendByte('}')
	return err
}

func (enc *consoleEncoder) AppendBool(val bool) {
	enc.buf.AppendBool(val)
}

func (enc *consoleEncoder) AppendByteString(val []byte) {
	enc.buf.AppendByte('"')
	enc.safeAddByteString(val)
	enc.buf.AppendByte('"')
}

func (enc *consoleEncoder) AppendComplex128(val complex128) {
	// Cast to a platform-independent, fixed-size type.
	r, i := float64(real(val)), float64(imag(val))
	enc.buf.AppendByte('"')
	// Because we're always in a quoted string, we can use strconv without
	// special-casing NaN and +/-Inf.
	enc.buf.AppendFloat(r, 64)
	enc.buf.AppendByte('+')
	enc.buf.AppendFloat(i, 64)
	enc.buf.AppendByte('i')
	enc.buf.AppendByte('"')
}

func (enc *consoleEncoder) AppendDuration(val time.Duration) {
	cur := enc.buf.Len()
	enc.EncodeDuration(val, enc)
	if cur == enc.buf.Len() {
		// User-supplied EncodeDuration is a no-op. Fall back to nanoseconds to keep
		// JSON valid.
		enc.AppendInt64(int64(val))
	}
}

func (enc *consoleEncoder) AppendInt64(val int64) {
	enc.buf.AppendInt(val)
}
func (enc *consoleEncoder) resetReflectBuf() {
	if enc.reflectBuf == nil {
		enc.reflectBuf = Get()
		enc.reflectEnc = json.NewEncoder(enc.reflectBuf)
	} else {
		enc.reflectBuf.Reset()
	}
}
func (enc *consoleEncoder) AppendReflected(val interface{}) error {
	enc.resetReflectBuf()
	err := enc.reflectEnc.Encode(val)
	if err != nil {
		return err
	}
	enc.reflectBuf.TrimNewline()
	_, err = enc.buf.Write(enc.reflectBuf.Bytes())
	return err
}

func (enc *consoleEncoder) AppendString(val string) {
	enc.safeAddString(val)
}

func (enc *consoleEncoder) AppendTime(val time.Time) {
	cur := enc.buf.Len()
	enc.EncodeTime(val, enc)
	if cur == enc.buf.Len() {
		// User-supplied EncodeTime is a no-op. Fall back to nanos since epoch to keep
		// output JSON valid.
		enc.AppendInt64(val.UnixNano())
	}
}

func (enc *consoleEncoder) AppendUint64(val uint64) {
	enc.buf.AppendUint(val)
}
func (enc *consoleEncoder) appendFloat(val float64, bitSize int) {
	switch {
	case math.IsNaN(val):
		enc.buf.AppendString(`"NaN"`)
	case math.IsInf(val, 1):
		enc.buf.AppendString(`"+Inf"`)
	case math.IsInf(val, -1):
		enc.buf.AppendString(`"-Inf"`)
	default:
		enc.buf.AppendFloat(val, bitSize)
	}
}

// safeAddString JSON-escapes a string and appends it to the internal buffer.
// Unlike the standard library's encoder, it doesn't attempt to protect the
// user from browser vulnerabilities or JSONP-related problems.
func (enc *consoleEncoder) safeAddString(s string) {
	for i := 0; i < len(s); {
		if enc.tryAddRuneSelf(s[i]) {
			i++
			continue
		}
		r, size := utf8.DecodeRuneInString(s[i:])
		if enc.tryAddRuneError(r, size) {
			i++
			continue
		}
		enc.buf.AppendString(s[i : i+size])
		i += size
	}
}

// safeAddByteString is no-alloc equivalent of safeAddString(string(s)) for s []byte.
func (enc *consoleEncoder) safeAddByteString(s []byte) {
	for i := 0; i < len(s); {
		if enc.tryAddRuneSelf(s[i]) {
			i++
			continue
		}
		r, size := utf8.DecodeRune(s[i:])
		if enc.tryAddRuneError(r, size) {
			i++
			continue
		}
		enc.buf.Write(s[i : i+size])
		i += size
	}
}

// tryAddRuneSelf appends b if it is valid UTF-8 character represented in a single byte.
func (enc *consoleEncoder) tryAddRuneSelf(b byte) bool {
	if b >= utf8.RuneSelf {
		return false
	}
	if 0x20 <= b && b != '\\' && b != '"' {
		enc.buf.AppendByte(b)
		return true
	}
	switch b {
	case '\\', '"':
		enc.buf.AppendByte('\\')
		enc.buf.AppendByte(b)
	case '\n':
		enc.buf.AppendByte('\\')
		enc.buf.AppendByte('n')
	case '\r':
		enc.buf.AppendByte('\\')
		enc.buf.AppendByte('r')
	case '\t':
		enc.buf.AppendByte('\\')
		enc.buf.AppendByte('t')
	default:
		// Encode bytes < 0x20, except for the escape sequences above.
		enc.buf.AppendString(`\u00`)
		enc.buf.AppendByte(_hex[b>>4])
		enc.buf.AppendByte(_hex[b&0xF])
	}
	return true
}
func (enc *consoleEncoder) closeOpenNamespaces() {
	for i := 0; i < enc.openNamespaces; i++ {
		enc.buf.AppendByte('}')
	}
}


func (enc *consoleEncoder) tryAddRuneError(r rune, size int) bool {
	if r == utf8.RuneError && size == 1 {
		enc.buf.AppendString(`\ufffd`)
		return true
	}
	return false
}
func (enc *consoleEncoder) AddComplex64(k string, v complex64) { enc.AddComplex128(k, complex128(v)) }
func (enc *consoleEncoder) AddFloat32(k string, v float32)     { enc.AddFloat64(k, float64(v)) }
func (enc *consoleEncoder) AddInt(k string, v int)             { enc.AddInt64(k, int64(v)) }
func (enc *consoleEncoder) AddInt32(k string, v int32)         { enc.AddInt64(k, int64(v)) }
func (enc *consoleEncoder) AddInt16(k string, v int16)         { enc.AddInt64(k, int64(v)) }
func (enc *consoleEncoder) AddInt8(k string, v int8)           { enc.AddInt64(k, int64(v)) }
func (enc *consoleEncoder) AddUint(k string, v uint)           { enc.AddUint64(k, uint64(v)) }
func (enc *consoleEncoder) AddUint32(k string, v uint32)       { enc.AddUint64(k, uint64(v)) }
func (enc *consoleEncoder) AddUint16(k string, v uint16)       { enc.AddUint64(k, uint64(v)) }
func (enc *consoleEncoder) AddUint8(k string, v uint8)         { enc.AddUint64(k, uint64(v)) }
func (enc *consoleEncoder) AddUintptr(k string, v uintptr)     { enc.AddUint64(k, uint64(v)) }
func (enc *consoleEncoder) AppendComplex64(v complex64)        { enc.AppendComplex128(complex128(v)) }
func (enc *consoleEncoder) AppendFloat64(v float64)            { enc.appendFloat(v, 64) }
func (enc *consoleEncoder) AppendFloat32(v float32)            { enc.appendFloat(float64(v), 32) }
func (enc *consoleEncoder) AppendInt(v int)                    { enc.AppendInt64(int64(v)) }
func (enc *consoleEncoder) AppendInt32(v int32)                { enc.AppendInt64(int64(v)) }
func (enc *consoleEncoder) AppendInt16(v int16)                { enc.AppendInt64(int64(v)) }
func (enc *consoleEncoder) AppendInt8(v int8)                  { enc.AppendInt64(int64(v)) }
func (enc *consoleEncoder) AppendUint(v uint)                  { enc.AppendUint64(uint64(v)) }
func (enc *consoleEncoder) AppendUint32(v uint32)              { enc.AppendUint64(uint64(v)) }
func (enc *consoleEncoder) AppendUint16(v uint16)              { enc.AppendUint64(uint64(v)) }
func (enc *consoleEncoder) AppendUint8(v uint8)                { enc.AppendUint64(uint64(v)) }
func (enc *consoleEncoder) AppendUintptr(v uintptr)            { enc.AppendUint64(uint64(v)) }

const _hex = "0123456789abcdef"

type sliceArrayEncoder struct {
	elems []interface{}
}

func (s *sliceArrayEncoder) AppendArray(v zapcore.ArrayMarshaler) error {
	enc := &sliceArrayEncoder{}
	err := v.MarshalLogArray(enc)
	s.elems = append(s.elems, enc.elems)
	return err
}

func (s *sliceArrayEncoder) AppendObject(v zapcore.ObjectMarshaler) error {
	m := zapcore.NewMapObjectEncoder()
	err := v.MarshalLogObject(m)
	s.elems = append(s.elems, m.Fields)
	return err
}

func (s *sliceArrayEncoder) AppendReflected(v interface{}) error {
	s.elems = append(s.elems, v)
	return nil
}

func (s *sliceArrayEncoder) AppendBool(v bool)              { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendByteString(v []byte)      { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendComplex128(v complex128)  { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendComplex64(v complex64)    { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendDuration(v time.Duration) { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendFloat64(v float64)        { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendFloat32(v float32)        { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendInt(v int)                { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendInt64(v int64)            { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendInt32(v int32)            { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendInt16(v int16)            { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendInt8(v int8)              { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendString(v string)          { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendTime(v time.Time)         { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendUint(v uint)              { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendUint64(v uint64)          { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendUint32(v uint32)          { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendUint16(v uint16)          { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendUint8(v uint8)            { s.elems = append(s.elems, v) }
func (s *sliceArrayEncoder) AppendUintptr(v uintptr)        { s.elems = append(s.elems, v) }