add vendor

vendor/github.com/couchbase/goutils/LICENSE.md

@@ -0,0 +1,47 @@
+COUCHBASE INC. COMMUNITY EDITION LICENSE AGREEMENT
+
+IMPORTANT-READ CAREFULLY: BY CLICKING THE "I ACCEPT" BOX OR INSTALLING,
+DOWNLOADING OR OTHERWISE USING THIS SOFTWARE AND ANY ASSOCIATED
+DOCUMENTATION, YOU, ON BEHALF OF YOURSELF OR AS AN AUTHORIZED
+REPRESENTATIVE ON BEHALF OF AN ENTITY ("LICENSEE") AGREE TO ALL THE
+TERMS OF THIS COMMUNITY EDITION LICENSE AGREEMENT (THE "AGREEMENT")
+REGARDING YOUR USE OF THE SOFTWARE.  YOU REPRESENT AND WARRANT THAT YOU
+HAVE FULL LEGAL AUTHORITY TO BIND THE LICENSEE TO THIS AGREEMENT. IF YOU
+DO NOT AGREE WITH ALL OF THESE TERMS, DO NOT SELECT THE "I ACCEPT" BOX
+AND DO NOT INSTALL, DOWNLOAD OR OTHERWISE USE THE SOFTWARE. THE
+EFFECTIVE DATE OF THIS AGREEMENT IS THE DATE ON WHICH YOU CLICK "I
+ACCEPT" OR OTHERWISE INSTALL, DOWNLOAD OR USE THE SOFTWARE.
+
+1. License Grant. Couchbase Inc. hereby grants Licensee, free of charge,
+the non-exclusive right to use, copy, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to
+whom the Software is furnished to do so, subject to Licensee including
+the following copyright notice in all copies or substantial portions of
+the Software:
+
+Couchbase (r) http://www.Couchbase.com Copyright 2016 Couchbase, Inc.
+
+As used in this Agreement, "Software" means the object code version of
+the applicable elastic data management server software provided by
+Couchbase Inc.
+
+2. Restrictions. Licensee will not reverse engineer, disassemble, or
+decompile the Software (except to the extent such restrictions are
+prohibited by law).
+
+3. Support. Couchbase, Inc. will provide Licensee with access to, and
+use of, the Couchbase, Inc. support forum available at the following
+URL: http://www.couchbase.org/forums/. Couchbase, Inc. may, at its
+discretion, modify, suspend or terminate support at any time upon notice
+to Licensee.
+
+4. Warranty Disclaimer and Limitation of Liability. THE SOFTWARE IS
+PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+COUCHBASE INC. OR THE AUTHORS OR COPYRIGHT HOLDERS IN THE SOFTWARE BE
+LIABLE FOR ANY CLAIM, DAMAGES (IINCLUDING, WITHOUT LIMITATION, DIRECT,
+INDIRECT OR CONSEQUENTIAL DAMAGES) OR OTHER LIABILITY, WHETHER IN AN
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/github.com/couchbase/goutils/logging/logger.go

@@ -0,0 +1,481 @@
+//  Copyright (c) 2016 Couchbase, Inc.
+//  Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+//  except in compliance with the License. You may obtain a copy of the License at
+//    http://www.apache.org/licenses/LICENSE-2.0
+//  Unless required by applicable law or agreed to in writing, software distributed under the
+//  License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+//  either express or implied. See the License for the specific language governing permissions
+//  and limitations under the License.
+
+package logging
+
+import (
+	"os"
+	"runtime"
+	"strings"
+	"sync"
+)
+
+type Level int
+
+const (
+	NONE    = Level(iota) // Disable all logging
+	FATAL                 // System is in severe error state and has to abort
+	SEVERE                // System is in severe error state and cannot recover reliably
+	ERROR                 // System is in error state but can recover and continue reliably
+	WARN                  // System approaching error state, or is in a correct but undesirable state
+	INFO                  // System-level events and status, in correct states
+	REQUEST               // Request-level events, with request-specific rlevel
+	TRACE                 // Trace detailed system execution, e.g. function entry / exit
+	DEBUG                 // Debug
+)
+
+type LogEntryFormatter int
+
+const (
+	TEXTFORMATTER = LogEntryFormatter(iota)
+	JSONFORMATTER
+	KVFORMATTER
+)
+
+func (level Level) String() string {
+	return _LEVEL_NAMES[level]
+}
+
+var _LEVEL_NAMES = []string{
+	DEBUG:   "DEBUG",
+	TRACE:   "TRACE",
+	REQUEST: "REQUEST",
+	INFO:    "INFO",
+	WARN:    "WARN",
+	ERROR:   "ERROR",
+	SEVERE:  "SEVERE",
+	FATAL:   "FATAL",
+	NONE:    "NONE",
+}
+
+var _LEVEL_MAP = map[string]Level{
+	"debug":   DEBUG,
+	"trace":   TRACE,
+	"request": REQUEST,
+	"info":    INFO,
+	"warn":    WARN,
+	"error":   ERROR,
+	"severe":  SEVERE,
+	"fatal":   FATAL,
+	"none":    NONE,
+}
+
+func ParseLevel(name string) (level Level, ok bool) {
+	level, ok = _LEVEL_MAP[strings.ToLower(name)]
+	return
+}
+
+/*
+
+Pair supports logging of key-value pairs.  Keys beginning with _ are
+reserved for the logger, e.g. _time, _level, _msg, and _rlevel. The
+Pair APIs are designed to avoid heap allocation and garbage
+collection.
+
+*/
+type Pairs []Pair
+type Pair struct {
+	Name  string
+	Value interface{}
+}
+
+/*
+
+Map allows key-value pairs to be specified using map literals or data
+structures. For example:
+
+Errorm(msg, Map{...})
+
+Map incurs heap allocation and garbage collection, so the Pair APIs
+should be preferred.
+
+*/
+type Map map[string]interface{}
+
+// Logger provides a common interface for logging libraries
+type Logger interface {
+	/*
+		These APIs write all the given pairs in addition to standard logger keys.
+	*/
+	Logp(level Level, msg string, kv ...Pair)
+
+	Debugp(msg string, kv ...Pair)
+
+	Tracep(msg string, kv ...Pair)
+
+	Requestp(rlevel Level, msg string, kv ...Pair)
+
+	Infop(msg string, kv ...Pair)
+
+	Warnp(msg string, kv ...Pair)
+
+	Errorp(msg string, kv ...Pair)
+
+	Severep(msg string, kv ...Pair)
+
+	Fatalp(msg string, kv ...Pair)
+
+	/*
+		These APIs write the fields in the given kv Map in addition to standard logger keys.
+	*/
+	Logm(level Level, msg string, kv Map)
+
+	Debugm(msg string, kv Map)
+
+	Tracem(msg string, kv Map)
+
+	Requestm(rlevel Level, msg string, kv Map)
+
+	Infom(msg string, kv Map)
+
+	Warnm(msg string, kv Map)
+
+	Errorm(msg string, kv Map)
+
+	Severem(msg string, kv Map)
+
+	Fatalm(msg string, kv Map)
+
+	/*
+
+		These APIs only write _msg, _time, _level, and other logger keys. If
+		the msg contains other fields, use the Pair or Map APIs instead.
+
+	*/
+	Logf(level Level, fmt string, args ...interface{})
+
+	Debugf(fmt string, args ...interface{})
+
+	Tracef(fmt string, args ...interface{})
+
+	Requestf(rlevel Level, fmt string, args ...interface{})
+
+	Infof(fmt string, args ...interface{})
+
+	Warnf(fmt string, args ...interface{})
+
+	Errorf(fmt string, args ...interface{})
+
+	Severef(fmt string, args ...interface{})
+
+	Fatalf(fmt string, args ...interface{})
+
+	/*
+		These APIs control the logging level
+	*/
+
+	SetLevel(Level) // Set the logging level
+
+	Level() Level // Get the current logging level
+}
+
+var logger Logger = nil
+var curLevel Level = DEBUG // initially set to never skip
+
+var loggerMutex sync.RWMutex
+
+// All the methods below first acquire the mutex (mostly in exclusive mode)
+// and only then check if logging at the current level is enabled.
+// This introduces a fair bottleneck for those log entries that should be
+// skipped (the majority, at INFO or below levels)
+// We try to predict here if we should lock the mutex at all by caching
+// the current log level: while dynamically changing logger, there might
+// be the odd entry skipped as the new level is cached.
+// Since we seem to never change the logger, this is not an issue.
+func skipLogging(level Level) bool {
+	if logger == nil {
+		return true
+	}
+	return level > curLevel
+}
+
+func SetLogger(newLogger Logger) {
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger = newLogger
+	if logger == nil {
+		curLevel = NONE
+	} else {
+		curLevel = newLogger.Level()
+	}
+}
+
+func Logp(level Level, msg string, kv ...Pair) {
+	if skipLogging(level) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Logp(level, msg, kv...)
+}
+
+func Debugp(msg string, kv ...Pair) {
+	if skipLogging(DEBUG) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Debugp(msg, kv...)
+}
+
+func Tracep(msg string, kv ...Pair) {
+	if skipLogging(TRACE) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Tracep(msg, kv...)
+}
+
+func Requestp(rlevel Level, msg string, kv ...Pair) {
+	if skipLogging(REQUEST) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Requestp(rlevel, msg, kv...)
+}
+
+func Infop(msg string, kv ...Pair) {
+	if skipLogging(INFO) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Infop(msg, kv...)
+}
+
+func Warnp(msg string, kv ...Pair) {
+	if skipLogging(WARN) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Warnp(msg, kv...)
+}
+
+func Errorp(msg string, kv ...Pair) {
+	if skipLogging(ERROR) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Errorp(msg, kv...)
+}
+
+func Severep(msg string, kv ...Pair) {
+	if skipLogging(SEVERE) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Severep(msg, kv...)
+}
+
+func Fatalp(msg string, kv ...Pair) {
+	if skipLogging(FATAL) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Fatalp(msg, kv...)
+}
+
+func Logm(level Level, msg string, kv Map) {
+	if skipLogging(level) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Logm(level, msg, kv)
+}
+
+func Debugm(msg string, kv Map) {
+	if skipLogging(DEBUG) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Debugm(msg, kv)
+}
+
+func Tracem(msg string, kv Map) {
+	if skipLogging(TRACE) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Tracem(msg, kv)
+}
+
+func Requestm(rlevel Level, msg string, kv Map) {
+	if skipLogging(REQUEST) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Requestm(rlevel, msg, kv)
+}
+
+func Infom(msg string, kv Map) {
+	if skipLogging(INFO) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Infom(msg, kv)
+}
+
+func Warnm(msg string, kv Map) {
+	if skipLogging(WARN) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Warnm(msg, kv)
+}
+
+func Errorm(msg string, kv Map) {
+	if skipLogging(ERROR) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Errorm(msg, kv)
+}
+
+func Severem(msg string, kv Map) {
+	if skipLogging(SEVERE) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Severem(msg, kv)
+}
+
+func Fatalm(msg string, kv Map) {
+	if skipLogging(FATAL) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Fatalm(msg, kv)
+}
+
+func Logf(level Level, fmt string, args ...interface{}) {
+	if skipLogging(level) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Logf(level, fmt, args...)
+}
+
+func Debugf(fmt string, args ...interface{}) {
+	if skipLogging(DEBUG) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Debugf(fmt, args...)
+}
+
+func Tracef(fmt string, args ...interface{}) {
+	if skipLogging(TRACE) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Tracef(fmt, args...)
+}
+
+func Requestf(rlevel Level, fmt string, args ...interface{}) {
+	if skipLogging(REQUEST) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Requestf(rlevel, fmt, args...)
+}
+
+func Infof(fmt string, args ...interface{}) {
+	if skipLogging(INFO) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Infof(fmt, args...)
+}
+
+func Warnf(fmt string, args ...interface{}) {
+	if skipLogging(WARN) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Warnf(fmt, args...)
+}
+
+func Errorf(fmt string, args ...interface{}) {
+	if skipLogging(ERROR) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Errorf(fmt, args...)
+}
+
+func Severef(fmt string, args ...interface{}) {
+	if skipLogging(SEVERE) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Severef(fmt, args...)
+}
+
+func Fatalf(fmt string, args ...interface{}) {
+	if skipLogging(FATAL) {
+		return
+	}
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Fatalf(fmt, args...)
+}
+
+func SetLevel(level Level) {
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.SetLevel(level)
+	curLevel = level
+}
+
+func LogLevel() Level {
+	loggerMutex.RLock()
+	defer loggerMutex.RUnlock()
+	return logger.Level()
+}
+
+func Stackf(level Level, fmt string, args ...interface{}) {
+	if skipLogging(level) {
+		return
+	}
+	buf := make([]byte, 1<<16)
+	n := runtime.Stack(buf, false)
+	s := string(buf[0:n])
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logger.Logf(level, fmt, args...)
+	logger.Logf(level, s)
+}
+
+func init() {
+	logger = NewLogger(os.Stderr, INFO, TEXTFORMATTER)
+	SetLogger(logger)
+}

vendor/github.com/couchbase/goutils/logging/logger_golog.go

@@ -0,0 +1,318 @@
+//  Copyright (c) 2016 Couchbase, Inc.
+//  Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+//  except in compliance with the License. You may obtain a copy of the License at
+//    http://www.apache.org/licenses/LICENSE-2.0
+//  Unless required by applicable law or agreed to in writing, software distributed under the
+//  License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+//  either express or implied. See the License for the specific language governing permissions
+//  and limitations under the License.
+
+package logging
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"time"
+)
+
+type goLogger struct {
+	logger         *log.Logger
+	level          Level
+	entryFormatter formatter
+}
+
+const (
+	_LEVEL  = "_level"
+	_MSG    = "_msg"
+	_TIME   = "_time"
+	_RLEVEL = "_rlevel"
+)
+
+func NewLogger(out io.Writer, lvl Level, fmtLogging LogEntryFormatter) *goLogger {
+	logger := &goLogger{
+		logger: log.New(out, "", 0),
+		level:  lvl,
+	}
+	if fmtLogging == JSONFORMATTER {
+		logger.entryFormatter = &jsonFormatter{}
+	} else if fmtLogging == KVFORMATTER {
+		logger.entryFormatter = &keyvalueFormatter{}
+	} else {
+		logger.entryFormatter = &textFormatter{}
+	}
+	return logger
+}
+
+func (gl *goLogger) Logp(level Level, msg string, kv ...Pair) {
+	if gl.logger == nil {
+		return
+	}
+	if level <= gl.level {
+		e := newLogEntry(msg, level)
+		copyPairs(e, kv)
+		gl.log(e)
+	}
+}
+
+func (gl *goLogger) Debugp(msg string, kv ...Pair) {
+	gl.Logp(DEBUG, msg, kv...)
+}
+
+func (gl *goLogger) Tracep(msg string, kv ...Pair) {
+	gl.Logp(TRACE, msg, kv...)
+}
+
+func (gl *goLogger) Requestp(rlevel Level, msg string, kv ...Pair) {
+	if gl.logger == nil {
+		return
+	}
+	if REQUEST <= gl.level {
+		e := newLogEntry(msg, REQUEST)
+		e.Rlevel = rlevel
+		copyPairs(e, kv)
+		gl.log(e)
+	}
+}
+
+func (gl *goLogger) Infop(msg string, kv ...Pair) {
+	gl.Logp(INFO, msg, kv...)
+}
+
+func (gl *goLogger) Warnp(msg string, kv ...Pair) {
+	gl.Logp(WARN, msg, kv...)
+}
+
+func (gl *goLogger) Errorp(msg string, kv ...Pair) {
+	gl.Logp(ERROR, msg, kv...)
+}
+
+func (gl *goLogger) Severep(msg string, kv ...Pair) {
+	gl.Logp(SEVERE, msg, kv...)
+}
+
+func (gl *goLogger) Fatalp(msg string, kv ...Pair) {
+	gl.Logp(FATAL, msg, kv...)
+}
+
+func (gl *goLogger) Logm(level Level, msg string, kv Map) {
+	if gl.logger == nil {
+		return
+	}
+	if level <= gl.level {
+		e := newLogEntry(msg, level)
+		e.Data = kv
+		gl.log(e)
+	}
+}
+
+func (gl *goLogger) Debugm(msg string, kv Map) {
+	gl.Logm(DEBUG, msg, kv)
+}
+
+func (gl *goLogger) Tracem(msg string, kv Map) {
+	gl.Logm(TRACE, msg, kv)
+}
+
+func (gl *goLogger) Requestm(rlevel Level, msg string, kv Map) {
+	if gl.logger == nil {
+		return
+	}
+	if REQUEST <= gl.level {
+		e := newLogEntry(msg, REQUEST)
+		e.Rlevel = rlevel
+		e.Data = kv
+		gl.log(e)
+	}
+}
+
+func (gl *goLogger) Infom(msg string, kv Map) {
+	gl.Logm(INFO, msg, kv)
+}
+
+func (gl *goLogger) Warnm(msg string, kv Map) {
+	gl.Logm(WARN, msg, kv)
+}
+
+func (gl *goLogger) Errorm(msg string, kv Map) {
+	gl.Logm(ERROR, msg, kv)
+}
+
+func (gl *goLogger) Severem(msg string, kv Map) {
+	gl.Logm(SEVERE, msg, kv)
+}
+
+func (gl *goLogger) Fatalm(msg string, kv Map) {
+	gl.Logm(FATAL, msg, kv)
+}
+
+func (gl *goLogger) Logf(level Level, format string, args ...interface{}) {
+	if gl.logger == nil {
+		return
+	}
+	if level <= gl.level {
+		e := newLogEntry(fmt.Sprintf(format, args...), level)
+		gl.log(e)
+	}
+}
+
+func (gl *goLogger) Debugf(format string, args ...interface{}) {
+	gl.Logf(DEBUG, format, args...)
+}
+
+func (gl *goLogger) Tracef(format string, args ...interface{}) {
+	gl.Logf(TRACE, format, args...)
+}
+
+func (gl *goLogger) Requestf(rlevel Level, format string, args ...interface{}) {
+	if gl.logger == nil {
+		return
+	}
+	if REQUEST <= gl.level {
+		e := newLogEntry(fmt.Sprintf(format, args...), REQUEST)
+		e.Rlevel = rlevel
+		gl.log(e)
+	}
+}
+
+func (gl *goLogger) Infof(format string, args ...interface{}) {
+	gl.Logf(INFO, format, args...)
+}
+
+func (gl *goLogger) Warnf(format string, args ...interface{}) {
+	gl.Logf(WARN, format, args...)
+}
+
+func (gl *goLogger) Errorf(format string, args ...interface{}) {
+	gl.Logf(ERROR, format, args...)
+}
+
+func (gl *goLogger) Severef(format string, args ...interface{}) {
+	gl.Logf(SEVERE, format, args...)
+}
+
+func (gl *goLogger) Fatalf(format string, args ...interface{}) {
+	gl.Logf(FATAL, format, args...)
+}
+
+func (gl *goLogger) Level() Level {
+	return gl.level
+}
+
+func (gl *goLogger) SetLevel(level Level) {
+	gl.level = level
+}
+
+func (gl *goLogger) log(newEntry *logEntry) {
+	s := gl.entryFormatter.format(newEntry)
+	gl.logger.Print(s)
+}
+
+type logEntry struct {
+	Time    string
+	Level   Level
+	Rlevel  Level
+	Message string
+	Data    Map
+}
+
+func newLogEntry(msg string, level Level) *logEntry {
+	return &logEntry{
+		Time:    time.Now().Format("2006-01-02T15:04:05.000-07:00"), // time.RFC3339 with milliseconds
+		Level:   level,
+		Rlevel:  NONE,
+		Message: msg,
+	}
+}
+
+func copyPairs(newEntry *logEntry, pairs []Pair) {
+	newEntry.Data = make(Map, len(pairs))
+	for _, p := range pairs {
+		newEntry.Data[p.Name] = p.Value
+	}
+}
+
+type formatter interface {
+	format(*logEntry) string
+}
+
+type textFormatter struct {
+}
+
+// ex. 2016-02-10T09:15:25.498-08:00 [INFO] This is a message from test in text format
+
+func (*textFormatter) format(newEntry *logEntry) string {
+	b := &bytes.Buffer{}
+	appendValue(b, newEntry.Time)
+	if newEntry.Rlevel != NONE {
+		fmt.Fprintf(b, "[%s,%s] ", newEntry.Level.String(), newEntry.Rlevel.String())
+	} else {
+		fmt.Fprintf(b, "[%s] ", newEntry.Level.String())
+	}
+	appendValue(b, newEntry.Message)
+	for key, value := range newEntry.Data {
+		appendKeyValue(b, key, value)
+	}
+	b.WriteByte('\n')
+	s := bytes.NewBuffer(b.Bytes())
+	return s.String()
+}
+
+func appendValue(b *bytes.Buffer, value interface{}) {
+	if _, ok := value.(string); ok {
+		fmt.Fprintf(b, "%s ", value)
+	} else {
+		fmt.Fprintf(b, "%v ", value)
+	}
+}
+
+type keyvalueFormatter struct {
+}
+
+// ex. _time=2016-02-10T09:15:25.498-08:00 _level=INFO _msg=This is a message from test in key-value format
+
+func (*keyvalueFormatter) format(newEntry *logEntry) string {
+	b := &bytes.Buffer{}
+	appendKeyValue(b, _TIME, newEntry.Time)
+	appendKeyValue(b, _LEVEL, newEntry.Level.String())
+	if newEntry.Rlevel != NONE {
+		appendKeyValue(b, _RLEVEL, newEntry.Rlevel.String())
+	}
+	appendKeyValue(b, _MSG, newEntry.Message)
+	for key, value := range newEntry.Data {
+		appendKeyValue(b, key, value)
+	}
+	b.WriteByte('\n')
+	s := bytes.NewBuffer(b.Bytes())
+	return s.String()
+}
+
+func appendKeyValue(b *bytes.Buffer, key, value interface{}) {
+	if _, ok := value.(string); ok {
+		fmt.Fprintf(b, "%v=%s ", key, value)
+	} else {
+		fmt.Fprintf(b, "%v=%v ", key, value)
+	}
+}
+
+type jsonFormatter struct {
+}
+
+// ex. {"_level":"INFO","_msg":"This is a message from test in json format","_time":"2016-02-10T09:12:59.518-08:00"}
+
+func (*jsonFormatter) format(newEntry *logEntry) string {
+	if newEntry.Data == nil {
+		newEntry.Data = make(Map, 5)
+	}
+	newEntry.Data[_TIME] = newEntry.Time
+	newEntry.Data[_LEVEL] = newEntry.Level.String()
+	if newEntry.Rlevel != NONE {
+		newEntry.Data[_RLEVEL] = newEntry.Rlevel.String()
+	}
+	newEntry.Data[_MSG] = newEntry.Message
+	serialized, _ := json.Marshal(newEntry.Data)
+	s := bytes.NewBuffer(append(serialized, '\n'))
+	return s.String()
+}