Merge branch 'add-logrus' into 'master'

Vendor logrus at v1.0.5

See merge request gitlab-org/gitlab-shell!197

go/vendor/github.com/sirupsen/logrus/CHANGELOG.md

+# 1.0.5
+
+* Fix hooks race (#707)
+* Fix panic deadlock (#695)
+
+# 1.0.4
+
+* Fix race when adding hooks (#612)
+* Fix terminal check in AppEngine (#635)
+
+# 1.0.3
+
+* Replace example files with testable examples
+
+# 1.0.2
+
+* bug: quote non-string values in text formatter (#583)
+* Make (*Logger) SetLevel a public method
+
+# 1.0.1
+
+* bug: fix escaping in text formatter (#575)
+
+# 1.0.0
+
+* Officially changed name to lower-case
+* bug: colors on Windows 10 (#541)
+* bug: fix race in accessing level (#512)
+
+# 0.11.5
+
+* feature: add writer and writerlevel to entry (#372)
+
+# 0.11.4
+
+* bug: fix undefined variable on solaris (#493)
+
+# 0.11.3
+
+* formatter: configure quoting of empty values (#484)
+* formatter: configure quoting character (default is `"`) (#484)
+* bug: fix not importing io correctly in non-linux environments (#481)
+
+# 0.11.2
+
+* bug: fix windows terminal detection (#476)
+
+# 0.11.1
+
+* bug: fix tty detection with custom out (#471)
+
+# 0.11.0
+
+* performance: Use bufferpool to allocate (#370)
+* terminal: terminal detection for app-engine (#343)
+* feature: exit handler (#375)
+
+# 0.10.0
+
+* feature: Add a test hook (#180)
+* feature: `ParseLevel` is now case-insensitive (#326)
+* feature: `FieldLogger` interface that generalizes `Logger` and `Entry` (#308)
+* performance: avoid re-allocations on `WithFields` (#335)
+
+# 0.9.0
+
+* logrus/text_formatter: don't emit empty msg
+* logrus/hooks/airbrake: move out of main repository
+* logrus/hooks/sentry: move out of main repository
+* logrus/hooks/papertrail: move out of main repository
+* logrus/hooks/bugsnag: move out of main repository
+* logrus/core: run tests with `-race`
+* logrus/core: detect TTY based on `stderr`
+* logrus/core: support `WithError` on logger
+* logrus/core: Solaris support
+
+# 0.8.7
+
+* logrus/core: fix possible race (#216)
+* logrus/doc: small typo fixes and doc improvements
+
+
+# 0.8.6
+
+* hooks/raven: allow passing an initialized client
+
+# 0.8.5
+
+* logrus/core: revert #208
+
+# 0.8.4
+
+* formatter/text: fix data race (#218)
+
+# 0.8.3
+
+* logrus/core: fix entry log level (#208)
+* logrus/core: improve performance of text formatter by 40%
+* logrus/core: expose `LevelHooks` type
+* logrus/core: add support for DragonflyBSD and NetBSD
+* formatter/text: print structs more verbosely
+
+# 0.8.2
+
+* logrus: fix more Fatal family functions
+
+# 0.8.1
+
+* logrus: fix not exiting on `Fatalf` and `Fatalln`
+
+# 0.8.0
+
+* logrus: defaults to stderr instead of stdout
+* hooks/sentry: add special field for `*http.Request`
+* formatter/text: ignore Windows for colors
+
+# 0.7.3
+
+* formatter/\*: allow configuration of timestamp layout
+
+# 0.7.2
+
+* formatter/text: Add configuration option for time format (#158)

go/vendor/github.com/sirupsen/logrus/LICENSE

+The MIT License (MIT)
+
+Copyright (c) 2014 Simon Eskildsen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, 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 the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+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 THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 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.

go/vendor/github.com/sirupsen/logrus/alt_exit.go

+package logrus
+
+// The following code was sourced and modified from the
+// https://github.com/tebeka/atexit package governed by the following license:
+//
+// Copyright (c) 2012 Miki Tebeka <miki.tebeka@gmail.com>.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, 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 the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// 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 THE AUTHORS OR
+// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 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.
+
+import (
+	"fmt"
+	"os"
+)
+
+var handlers = []func(){}
+
+func runHandler(handler func()) {
+	defer func() {
+		if err := recover(); err != nil {
+			fmt.Fprintln(os.Stderr, "Error: Logrus exit handler error:", err)
+		}
+	}()
+
+	handler()
+}
+
+func runHandlers() {
+	for _, handler := range handlers {
+		runHandler(handler)
+	}
+}
+
+// Exit runs all the Logrus atexit handlers and then terminates the program using os.Exit(code)
+func Exit(code int) {
+	runHandlers()
+	os.Exit(code)
+}
+
+// RegisterExitHandler adds a Logrus Exit handler, call logrus.Exit to invoke
+// all handlers. The handlers will also be invoked when any Fatal log entry is
+// made.
+//
+// This method is useful when a caller wishes to use logrus to log a fatal
+// message but also needs to gracefully shutdown. An example usecase could be
+// closing database connections, or sending a alert that the application is
+// closing.
+func RegisterExitHandler(handler func()) {
+	handlers = append(handlers, handler)
+}

go/vendor/github.com/sirupsen/logrus/appveyor.yml

+version: "{build}"
+platform: x64
+clone_folder: c:\gopath\src\github.com\sirupsen\logrus
+environment:  
+  GOPATH: c:\gopath
+branches:  
+  only:
+    - master
+install:  
+  - set PATH=%GOPATH%\bin;c:\go\bin;%PATH%
+  - go version
+build_script:  
+  - go get -t
+  - go test

go/vendor/github.com/sirupsen/logrus/doc.go

+/*
+Package logrus is a structured logger for Go, completely API compatible with the standard library logger.
+
+
+The simplest way to use Logrus is simply the package-level exported logger:
+
+  package main
+
+  import (
+    log "github.com/sirupsen/logrus"
+  )
+
+  func main() {
+    log.WithFields(log.Fields{
+      "animal": "walrus",
+      "number": 1,
+      "size":   10,
+    }).Info("A walrus appears")
+  }
+
+Output:
+  time="2015-09-07T08:48:33Z" level=info msg="A walrus appears" animal=walrus number=1 size=10
+
+For a full guide visit https://github.com/sirupsen/logrus
+*/
+package logrus

go/vendor/github.com/sirupsen/logrus/entry.go

+package logrus
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"sync"
+	"time"
+)
+
+var bufferPool *sync.Pool
+
+func init() {
+	bufferPool = &sync.Pool{
+		New: func() interface{} {
+			return new(bytes.Buffer)
+		},
+	}
+}
+
+// Defines the key when adding errors using WithError.
+var ErrorKey = "error"
+
+// An entry is the final or intermediate Logrus logging entry. It contains all
+// the fields passed with WithField{,s}. It's finally logged when Debug, Info,
+// Warn, Error, Fatal or Panic is called on it. These objects can be reused and
+// passed around as much as you wish to avoid field duplication.
+type Entry struct {
+	Logger *Logger
+
+	// Contains all the fields set by the user.
+	Data Fields
+
+	// Time at which the log entry was created
+	Time time.Time
+
+	// Level the log entry was logged at: Debug, Info, Warn, Error, Fatal or Panic
+	// This field will be set on entry firing and the value will be equal to the one in Logger struct field.
+	Level Level
+
+	// Message passed to Debug, Info, Warn, Error, Fatal or Panic
+	Message string
+
+	// When formatter is called in entry.log(), an Buffer may be set to entry
+	Buffer *bytes.Buffer
+}
+
+func NewEntry(logger *Logger) *Entry {
+	return &Entry{
+		Logger: logger,
+		// Default is three fields, give a little extra room
+		Data: make(Fields, 5),
+	}
+}
+
+// Returns the string representation from the reader and ultimately the
+// formatter.
+func (entry *Entry) String() (string, error) {
+	serialized, err := entry.Logger.Formatter.Format(entry)
+	if err != nil {
+		return "", err
+	}
+	str := string(serialized)
+	return str, nil
+}
+
+// Add an error as single field (using the key defined in ErrorKey) to the Entry.
+func (entry *Entry) WithError(err error) *Entry {
+	return entry.WithField(ErrorKey, err)
+}
+
+// Add a single field to the Entry.
+func (entry *Entry) WithField(key string, value interface{}) *Entry {
+	return entry.WithFields(Fields{key: value})
+}
+
+// Add a map of fields to the Entry.
+func (entry *Entry) WithFields(fields Fields) *Entry {
+	data := make(Fields, len(entry.Data)+len(fields))
+	for k, v := range entry.Data {
+		data[k] = v
+	}
+	for k, v := range fields {
+		data[k] = v
+	}
+	return &Entry{Logger: entry.Logger, Data: data}
+}
+
+// This function is not declared with a pointer value because otherwise
+// race conditions will occur when using multiple goroutines
+func (entry Entry) log(level Level, msg string) {
+	var buffer *bytes.Buffer
+	entry.Time = time.Now()
+	entry.Level = level
+	entry.Message = msg
+
+	entry.fireHooks()
+
+	buffer = bufferPool.Get().(*bytes.Buffer)
+	buffer.Reset()
+	defer bufferPool.Put(buffer)
+	entry.Buffer = buffer
+
+	entry.write()
+
+	entry.Buffer = nil
+
+	// To avoid Entry#log() returning a value that only would make sense for
+	// panic() to use in Entry#Panic(), we avoid the allocation by checking
+	// directly here.
+	if level <= PanicLevel {
+		panic(&entry)
+	}
+}
+
+// This function is not declared with a pointer value because otherwise
+// race conditions will occur when using multiple goroutines
+func (entry Entry) fireHooks() {
+	entry.Logger.mu.Lock()
+	defer entry.Logger.mu.Unlock()
+	err := entry.Logger.Hooks.Fire(entry.Level, &entry)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to fire hook: %v\n", err)
+	}
+}
+
+func (entry *Entry) write() {
+	serialized, err := entry.Logger.Formatter.Format(entry)
+	entry.Logger.mu.Lock()
+	defer entry.Logger.mu.Unlock()
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to obtain reader, %v\n", err)
+	} else {
+		_, err = entry.Logger.Out.Write(serialized)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Failed to write to log, %v\n", err)
+		}
+	}
+}
+
+func (entry *Entry) Debug(args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.log(DebugLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Print(args ...interface{}) {
+	entry.Info(args...)
+}
+
+func (entry *Entry) Info(args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.log(InfoLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Warn(args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.log(WarnLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Warning(args ...interface{}) {
+	entry.Warn(args...)
+}
+
+func (entry *Entry) Error(args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.log(ErrorLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Fatal(args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.log(FatalLevel, fmt.Sprint(args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panic(args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.log(PanicLevel, fmt.Sprint(args...))
+	}
+	panic(fmt.Sprint(args...))
+}
+
+// Entry Printf family functions
+
+func (entry *Entry) Debugf(format string, args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.Debug(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Infof(format string, args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.Info(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Printf(format string, args ...interface{}) {
+	entry.Infof(format, args...)
+}
+
+func (entry *Entry) Warnf(format string, args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.Warn(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Warningf(format string, args ...interface{}) {
+	entry.Warnf(format, args...)
+}
+
+func (entry *Entry) Errorf(format string, args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.Error(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Fatalf(format string, args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.Fatal(fmt.Sprintf(format, args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panicf(format string, args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.Panic(fmt.Sprintf(format, args...))
+	}
+}
+
+// Entry Println family functions
+
+func (entry *Entry) Debugln(args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.Debug(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Infoln(args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.Info(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Println(args ...interface{}) {
+	entry.Infoln(args...)
+}
+
+func (entry *Entry) Warnln(args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.Warn(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Warningln(args ...interface{}) {
+	entry.Warnln(args...)
+}
+
+func (entry *Entry) Errorln(args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.Error(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Fatalln(args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.Fatal(entry.sprintlnn(args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panicln(args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.Panic(entry.sprintlnn(args...))
+	}
+}
+
+// Sprintlnn => Sprint no newline. This is to get the behavior of how
+// fmt.Sprintln where spaces are always added between operands, regardless of
+// their type. Instead of vendoring the Sprintln implementation to spare a
+// string allocation, we do the simplest thing.
+func (entry *Entry) sprintlnn(args ...interface{}) string {
+	msg := fmt.Sprintln(args...)
+	return msg[:len(msg)-1]
+}

go/vendor/github.com/sirupsen/logrus/exported.go

+package logrus
+
+import (
+	"io"
+)
+
+var (
+	// std is the name of the standard logger in stdlib `log`
+	std = New()
+)
+
+func StandardLogger() *Logger {
+	return std
+}
+
+// SetOutput sets the standard logger output.
+func SetOutput(out io.Writer) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Out = out
+}
+
+// SetFormatter sets the standard logger formatter.
+func SetFormatter(formatter Formatter) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Formatter = formatter
+}
+
+// SetLevel sets the standard logger level.
+func SetLevel(level Level) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.SetLevel(level)
+}
+
+// GetLevel returns the standard logger level.
+func GetLevel() Level {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	return std.level()
+}
+
+// AddHook adds a hook to the standard logger hooks.
+func AddHook(hook Hook) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Hooks.Add(hook)
+}
+
+// WithError creates an entry from the standard logger and adds an error to it, using the value defined in ErrorKey as key.
+func WithError(err error) *Entry {
+	return std.WithField(ErrorKey, err)
+}
+
+// WithField creates an entry from the standard logger and adds a field to
+// it. If you want multiple fields, use `WithFields`.
+//
+// Note that it doesn't log until you call Debug, Print, Info, Warn, Fatal
+// or Panic on the Entry it returns.
+func WithField(key string, value interface{}) *Entry {
+	return std.WithField(key, value)
+}
+
+// WithFields creates an entry from the standard logger and adds multiple
+// fields to it. This is simply a helper for `WithField`, invoking it
+// once for each field.
+//
+// Note that it doesn't log until you call Debug, Print, Info, Warn, Fatal
+// or Panic on the Entry it returns.
+func WithFields(fields Fields) *Entry {
+	return std.WithFields(fields)
+}
+
+// Debug logs a message at level Debug on the standard logger.
+func Debug(args ...interface{}) {
+	std.Debug(args...)
+}
+
+// Print logs a message at level Info on the standard logger.
+func Print(args ...interface{}) {
+	std.Print(args...)
+}
+
+// Info logs a message at level Info on the standard logger.
+func Info(args ...interface{}) {
+	std.Info(args...)
+}
+
+// Warn logs a message at level Warn on the standard logger.
+func Warn(args ...interface{}) {
+	std.Warn(args...)
+}
+
+// Warning logs a message at level Warn on the standard logger.
+func Warning(args ...interface{}) {
+	std.Warning(args...)
+}
+
+// Error logs a message at level Error on the standard logger.
+func Error(args ...interface{}) {
+	std.Error(args...)
+}
+
+// Panic logs a message at level Panic on the standard logger.
+func Panic(args ...interface{}) {
+	std.Panic(args...)
+}
+
+// Fatal logs a message at level Fatal on the standard logger.
+func Fatal(args ...interface{}) {
+	std.Fatal(args...)
+}
+
+// Debugf logs a message at level Debug on the standard logger.
+func Debugf(format string, args ...interface{}) {
+	std.Debugf(format, args...)
+}
+
+// Printf logs a message at level Info on the standard logger.
+func Printf(format string, args ...interface{}) {
+	std.Printf(format, args...)
+}
+
+// Infof logs a message at level Info on the standard logger.
+func Infof(format string, args ...interface{}) {
+	std.Infof(format, args...)
+}
+
+// Warnf logs a message at level Warn on the standard logger.
+func Warnf(format string, args ...interface{}) {
+	std.Warnf(format, args...)
+}
+
+// Warningf logs a message at level Warn on the standard logger.
+func Warningf(format string, args ...interface{}) {
+	std.Warningf(format, args...)
+}
+
+// Errorf logs a message at level Error on the standard logger.
+func Errorf(format string, args ...interface{}) {
+	std.Errorf(format, args...)
+}
+
+// Panicf logs a message at level Panic on the standard logger.
+func Panicf(format string, args ...interface{}) {
+	std.Panicf(format, args...)
+}
+
+// Fatalf logs a message at level Fatal on the standard logger.
+func Fatalf(format string, args ...interface{}) {
+	std.Fatalf(format, args...)
+}
+
+// Debugln logs a message at level Debug on the standard logger.
+func Debugln(args ...interface{}) {
+	std.Debugln(args...)
+}
+
+// Println logs a message at level Info on the standard logger.
+func Println(args ...interface{}) {
+	std.Println(args...)
+}
+
+// Infoln logs a message at level Info on the standard logger.
+func Infoln(args ...interface{}) {
+	std.Infoln(args...)
+}
+
+// Warnln logs a message at level Warn on the standard logger.
+func Warnln(args ...interface{}) {
+	std.Warnln(args...)
+}
+
+// Warningln logs a message at level Warn on the standard logger.
+func Warningln(args ...interface{}) {
+	std.Warningln(args...)
+}
+
+// Errorln logs a message at level Error on the standard logger.
+func Errorln(args ...interface{}) {
+	std.Errorln(args...)
+}
+
+// Panicln logs a message at level Panic on the standard logger.
+func Panicln(args ...interface{}) {
+	std.Panicln(args...)
+}
+
+// Fatalln logs a message at level Fatal on the standard logger.
+func Fatalln(args ...interface{}) {
+	std.Fatalln(args...)
+}

go/vendor/github.com/sirupsen/logrus/formatter.go

+package logrus
+
+import "time"
+
+const defaultTimestampFormat = time.RFC3339
+
+// The Formatter interface is used to implement a custom Formatter. It takes an
+// `Entry`. It exposes all the fields, including the default ones:
+//
+// * `entry.Data["msg"]`. The message passed from Info, Warn, Error ..
+// * `entry.Data["time"]`. The timestamp.
+// * `entry.Data["level"]. The level the entry was logged at.
+//
+// Any additional fields added with `WithField` or `WithFields` are also in
+// `entry.Data`. Format is expected to return an array of bytes which are then
+// logged to `logger.Out`.
+type Formatter interface {
+	Format(*Entry) ([]byte, error)
+}
+
+// This is to not silently overwrite `time`, `msg` and `level` fields when
+// dumping it. If this code wasn't there doing:
+//
+//  logrus.WithField("level", 1).Info("hello")
+//
+// Would just silently drop the user provided level. Instead with this code
+// it'll logged as:
+//
+//  {"level": "info", "fields.level": 1, "msg": "hello", "time": "..."}
+//
+// It's not exported because it's still using Data in an opinionated way. It's to
+// avoid code duplication between the two default formatters.
+func prefixFieldClashes(data Fields) {
+	if t, ok := data["time"]; ok {
+		data["fields.time"] = t
+	}
+
+	if m, ok := data["msg"]; ok {
+		data["fields.msg"] = m
+	}
+
+	if l, ok := data["level"]; ok {
+		data["fields.level"] = l
+	}
+}

go/vendor/github.com/sirupsen/logrus/hooks.go

+package logrus
+
+// A hook to be fired when logging on the logging levels returned from
+// `Levels()` on your implementation of the interface. Note that this is not
+// fired in a goroutine or a channel with workers, you should handle such
+// functionality yourself if your call is non-blocking and you don't wish for
+// the logging calls for levels returned from `Levels()` to block.
+type Hook interface {
+	Levels() []Level
+	Fire(*Entry) error
+}
+
+// Internal type for storing the hooks on a logger instance.
+type LevelHooks map[Level][]Hook
+
+// Add a hook to an instance of logger. This is called with
+// `log.Hooks.Add(new(MyHook))` where `MyHook` implements the `Hook` interface.
+func (hooks LevelHooks) Add(hook Hook) {
+	for _, level := range hook.Levels() {
+		hooks[level] = append(hooks[level], hook)
+	}
+}
+
+// Fire all the hooks for the passed level. Used by `entry.log` to fire
+// appropriate hooks for a log entry.
+func (hooks LevelHooks) Fire(level Level, entry *Entry) error {
+	for _, hook := range hooks[level] {
+		if err := hook.Fire(entry); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

go/vendor/github.com/sirupsen/logrus/json_formatter.go

+package logrus
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+type fieldKey string
+
+// FieldMap allows customization of the key names for default fields.
+type FieldMap map[fieldKey]string
+
+// Default key names for the default fields
+const (
+	FieldKeyMsg   = "msg"
+	FieldKeyLevel = "level"
+	FieldKeyTime  = "time"
+)
+
+func (f FieldMap) resolve(key fieldKey) string {
+	if k, ok := f[key]; ok {
+		return k
+	}
+
+	return string(key)
+}
+
+// JSONFormatter formats logs into parsable json
+type JSONFormatter struct {
+	// TimestampFormat sets the format used for marshaling timestamps.
+	TimestampFormat string
+
+	// DisableTimestamp allows disabling automatic timestamps in output
+	DisableTimestamp bool
+
+	// FieldMap allows users to customize the names of keys for default fields.
+	// As an example:
+	// formatter := &JSONFormatter{
+	//   	FieldMap: FieldMap{
+	// 		 FieldKeyTime: "@timestamp",
+	// 		 FieldKeyLevel: "@level",
+	// 		 FieldKeyMsg: "@message",
+	//    },
+	// }
+	FieldMap FieldMap
+}
+
+// Format renders a single log entry
+func (f *JSONFormatter) Format(entry *Entry) ([]byte, error) {
+	data := make(Fields, len(entry.Data)+3)
+	for k, v := range entry.Data {
+		switch v := v.(type) {
+		case error:
+			// Otherwise errors are ignored by `encoding/json`
+			// https://github.com/sirupsen/logrus/issues/137
+			data[k] = v.Error()
+		default:
+			data[k] = v
+		}
+	}
+	prefixFieldClashes(data)
+
+	timestampFormat := f.TimestampFormat
+	if timestampFormat == "" {
+		timestampFormat = defaultTimestampFormat
+	}
+
+	if !f.DisableTimestamp {
+		data[f.FieldMap.resolve(FieldKeyTime)] = entry.Time.Format(timestampFormat)
+	}
+	data[f.FieldMap.resolve(FieldKeyMsg)] = entry.Message
+	data[f.FieldMap.resolve(FieldKeyLevel)] = entry.Level.String()
+
+	serialized, err := json.Marshal(data)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err)
+	}
+	return append(serialized, '\n'), nil
+}

go/vendor/github.com/sirupsen/logrus/logger.go

+package logrus
+
+import (
+	"io"
+	"os"
+	"sync"
+	"sync/atomic"
+)
+
+type Logger struct {
+	// The logs are `io.Copy`'d to this in a mutex. It's common to set this to a
+	// file, or leave it default which is `os.Stderr`. You can also set this to
+	// something more adventorous, such as logging to Kafka.
+	Out io.Writer
+	// Hooks for the logger instance. These allow firing events based on logging
+	// levels and log entries. For example, to send errors to an error tracking
+	// service, log to StatsD or dump the core on fatal errors.
+	Hooks LevelHooks
+	// All log entries pass through the formatter before logged to Out. The
+	// included formatters are `TextFormatter` and `JSONFormatter` for which
+	// TextFormatter is the default. In development (when a TTY is attached) it
+	// logs with colors, but to a file it wouldn't. You can easily implement your
+	// own that implements the `Formatter` interface, see the `README` or included
+	// formatters for examples.
+	Formatter Formatter
+	// The logging level the logger should log at. This is typically (and defaults
+	// to) `logrus.Info`, which allows Info(), Warn(), Error() and Fatal() to be
+	// logged.
+	Level Level
+	// Used to sync writing to the log. Locking is enabled by Default
+	mu MutexWrap
+	// Reusable empty entry
+	entryPool sync.Pool
+}
+
+type MutexWrap struct {
+	lock     sync.Mutex
+	disabled bool
+}
+
+func (mw *MutexWrap) Lock() {
+	if !mw.disabled {
+		mw.lock.Lock()
+	}
+}
+
+func (mw *MutexWrap) Unlock() {
+	if !mw.disabled {
+		mw.lock.Unlock()
+	}
+}
+
+func (mw *MutexWrap) Disable() {
+	mw.disabled = true
+}
+
+// Creates a new logger. Configuration should be set by changing `Formatter`,
+// `Out` and `Hooks` directly on the default logger instance. You can also just
+// instantiate your own:
+//
+//    var log = &Logger{
+//      Out: os.Stderr,
+//      Formatter: new(JSONFormatter),
+//      Hooks: make(LevelHooks),
+//      Level: logrus.DebugLevel,
+//    }
+//
+// It's recommended to make this a global instance called `log`.
+func New() *Logger {
+	return &Logger{
+		Out:       os.Stderr,
+		Formatter: new(TextFormatter),
+		Hooks:     make(LevelHooks),
+		Level:     InfoLevel,
+	}
+}
+
+func (logger *Logger) newEntry() *Entry {
+	entry, ok := logger.entryPool.Get().(*Entry)
+	if ok {
+		return entry
+	}
+	return NewEntry(logger)
+}
+
+func (logger *Logger) releaseEntry(entry *Entry) {
+	logger.entryPool.Put(entry)
+}
+
+// Adds a field to the log entry, note that it doesn't log until you call
+// Debug, Print, Info, Warn, Fatal or Panic. It only creates a log entry.
+// If you want multiple fields, use `WithFields`.
+func (logger *Logger) WithField(key string, value interface{}) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithField(key, value)
+}
+
+// Adds a struct of fields to the log entry. All it does is call `WithField` for
+// each `Field`.
+func (logger *Logger) WithFields(fields Fields) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithFields(fields)
+}
+
+// Add an error as single field to the log entry.  All it does is call
+// `WithError` for the given `error`.
+func (logger *Logger) WithError(err error) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithError(err)
+}
+
+func (logger *Logger) Debugf(format string, args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debugf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Infof(format string, args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Infof(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Printf(format string, args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Printf(format, args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warnf(format string, args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warningf(format string, args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Errorf(format string, args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Errorf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatalf(format string, args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatalf(format, args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panicf(format string, args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panicf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Debug(args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debug(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Info(args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Info(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Print(args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Info(args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warn(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warn(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warning(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warn(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Error(args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Error(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatal(args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatal(args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panic(args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panic(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Debugln(args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debugln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Infoln(args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Infoln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Println(args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Println(args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warnln(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warningln(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Errorln(args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Errorln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatalln(args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatalln(args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panicln(args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panicln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+//When file is opened with appending mode, it's safe to
+//write concurrently to a file (within 4k message on Linux).
+//In these cases user can choose to disable the lock.
+func (logger *Logger) SetNoLock() {
+	logger.mu.Disable()
+}
+
+func (logger *Logger) level() Level {
+	return Level(atomic.LoadUint32((*uint32)(&logger.Level)))
+}
+
+func (logger *Logger) SetLevel(level Level) {
+	atomic.StoreUint32((*uint32)(&logger.Level), uint32(level))
+}
+
+func (logger *Logger) AddHook(hook Hook) {
+	logger.mu.Lock()
+	defer logger.mu.Unlock()
+	logger.Hooks.Add(hook)
+}

go/vendor/github.com/sirupsen/logrus/logrus.go

+package logrus
+
+import (
+	"fmt"
+	"log"
+	"strings"
+)
+
+// Fields type, used to pass to `WithFields`.
+type Fields map[string]interface{}
+
+// Level type
+type Level uint32
+
+// Convert the Level to a string. E.g. PanicLevel becomes "panic".
+func (level Level) String() string {
+	switch level {
+	case DebugLevel:
+		return "debug"
+	case InfoLevel:
+		return "info"
+	case WarnLevel:
+		return "warning"
+	case ErrorLevel:
+		return "error"
+	case FatalLevel:
+		return "fatal"
+	case PanicLevel:
+		return "panic"
+	}
+
+	return "unknown"
+}
+
+// ParseLevel takes a string level and returns the Logrus log level constant.
+func ParseLevel(lvl string) (Level, error) {
+	switch strings.ToLower(lvl) {
+	case "panic":
+		return PanicLevel, nil
+	case "fatal":
+		return FatalLevel, nil
+	case "error":
+		return ErrorLevel, nil
+	case "warn", "warning":
+		return WarnLevel, nil
+	case "info":
+		return InfoLevel, nil
+	case "debug":
+		return DebugLevel, nil
+	}
+
+	var l Level
+	return l, fmt.Errorf("not a valid logrus Level: %q", lvl)
+}
+
+// A constant exposing all logging levels
+var AllLevels = []Level{
+	PanicLevel,
+	FatalLevel,
+	ErrorLevel,
+	WarnLevel,
+	InfoLevel,
+	DebugLevel,
+}
+
+// These are the different logging levels. You can set the logging level to log
+// on your instance of logger, obtained with `logrus.New()`.
+const (
+	// PanicLevel level, highest level of severity. Logs and then calls panic with the
+	// message passed to Debug, Info, ...
+	PanicLevel Level = iota
+	// FatalLevel level. Logs and then calls `os.Exit(1)`. It will exit even if the
+	// logging level is set to Panic.
+	FatalLevel
+	// ErrorLevel level. Logs. Used for errors that should definitely be noted.
+	// Commonly used for hooks to send errors to an error tracking service.
+	ErrorLevel
+	// WarnLevel level. Non-critical entries that deserve eyes.
+	WarnLevel
+	// InfoLevel level. General operational entries about what's going on inside the
+	// application.
+	InfoLevel
+	// DebugLevel level. Usually only enabled when debugging. Very verbose logging.
+	DebugLevel
+)
+
+// Won't compile if StdLogger can't be realized by a log.Logger
+var (
+	_ StdLogger = &log.Logger{}
+	_ StdLogger = &Entry{}
+	_ StdLogger = &Logger{}
+)
+
+// StdLogger is what your logrus-enabled library should take, that way
+// it'll accept a stdlib logger and a logrus logger. There's no standard
+// interface, this is the closest we get, unfortunately.
+type StdLogger interface {
+	Print(...interface{})
+	Printf(string, ...interface{})
+	Println(...interface{})
+
+	Fatal(...interface{})
+	Fatalf(string, ...interface{})
+	Fatalln(...interface{})
+
+	Panic(...interface{})
+	Panicf(string, ...interface{})
+	Panicln(...interface{})
+}
+
+// The FieldLogger interface generalizes the Entry and Logger types
+type FieldLogger interface {
+	WithField(key string, value interface{}) *Entry
+	WithFields(fields Fields) *Entry
+	WithError(err error) *Entry
+
+	Debugf(format string, args ...interface{})
+	Infof(format string, args ...interface{})
+	Printf(format string, args ...interface{})
+	Warnf(format string, args ...interface{})
+	Warningf(format string, args ...interface{})
+	Errorf(format string, args ...interface{})
+	Fatalf(format string, args ...interface{})
+	Panicf(format string, args ...interface{})
+
+	Debug(args ...interface{})
+	Info(args ...interface{})
+	Print(args ...interface{})
+	Warn(args ...interface{})
+	Warning(args ...interface{})
+	Error(args ...interface{})
+	Fatal(args ...interface{})
+	Panic(args ...interface{})
+
+	Debugln(args ...interface{})
+	Infoln(args ...interface{})
+	Println(args ...interface{})
+	Warnln(args ...interface{})
+	Warningln(args ...interface{})
+	Errorln(args ...interface{})
+	Fatalln(args ...interface{})
+	Panicln(args ...interface{})
+}

go/vendor/github.com/sirupsen/logrus/terminal_bsd.go

+// +build darwin freebsd openbsd netbsd dragonfly
+// +build !appengine,!gopherjs
+
+package logrus
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TIOCGETA
+
+type Termios unix.Termios

go/vendor/github.com/sirupsen/logrus/terminal_check_appengine.go

+// +build appengine gopherjs
+
+package logrus
+
+import (
+	"io"
+)
+
+func checkIfTerminal(w io.Writer) bool {
+	return true
+}

go/vendor/github.com/sirupsen/logrus/terminal_check_notappengine.go

+// +build !appengine,!gopherjs
+
+package logrus
+
+import (
+	"io"
+	"os"
+
+	"golang.org/x/crypto/ssh/terminal"
+)
+
+func checkIfTerminal(w io.Writer) bool {
+	switch v := w.(type) {
+	case *os.File:
+		return terminal.IsTerminal(int(v.Fd()))
+	default:
+		return false
+	}
+}

go/vendor/github.com/sirupsen/logrus/terminal_linux.go

+// Based on ssh/terminal:
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !appengine,!gopherjs
+
+package logrus
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TCGETS
+
+type Termios unix.Termios

go/vendor/github.com/sirupsen/logrus/text_formatter.go

+package logrus
+
+import (
+	"bytes"
+	"fmt"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	nocolor = 0
+	red     = 31
+	green   = 32
+	yellow  = 33
+	blue    = 36
+	gray    = 37
+)
+
+var (
+	baseTimestamp time.Time
+)
+
+func init() {
+	baseTimestamp = time.Now()
+}
+
+// TextFormatter formats logs into text
+type TextFormatter struct {
+	// Set to true to bypass checking for a TTY before outputting colors.
+	ForceColors bool
+
+	// Force disabling colors.
+	DisableColors bool
+
+	// Disable timestamp logging. useful when output is redirected to logging
+	// system that already adds timestamps.
+	DisableTimestamp bool
+
+	// Enable logging the full timestamp when a TTY is attached instead of just
+	// the time passed since beginning of execution.
+	FullTimestamp bool
+
+	// TimestampFormat to use for display when a full timestamp is printed
+	TimestampFormat string
+
+	// The fields are sorted by default for a consistent output. For applications
+	// that log extremely frequently and don't use the JSON formatter this may not
+	// be desired.
+	DisableSorting bool
+
+	// QuoteEmptyFields will wrap empty fields in quotes if true
+	QuoteEmptyFields bool
+
+	// Whether the logger's out is to a terminal
+	isTerminal bool
+
+	sync.Once
+}
+
+func (f *TextFormatter) init(entry *Entry) {
+	if entry.Logger != nil {
+		f.isTerminal = checkIfTerminal(entry.Logger.Out)
+	}
+}
+
+// Format renders a single log entry
+func (f *TextFormatter) Format(entry *Entry) ([]byte, error) {
+	var b *bytes.Buffer
+	keys := make([]string, 0, len(entry.Data))
+	for k := range entry.Data {
+		keys = append(keys, k)
+	}
+
+	if !f.DisableSorting {
+		sort.Strings(keys)
+	}
+	if entry.Buffer != nil {
+		b = entry.Buffer
+	} else {
+		b = &bytes.Buffer{}
+	}
+
+	prefixFieldClashes(entry.Data)
+
+	f.Do(func() { f.init(entry) })
+
+	isColored := (f.ForceColors || f.isTerminal) && !f.DisableColors
+
+	timestampFormat := f.TimestampFormat
+	if timestampFormat == "" {
+		timestampFormat = defaultTimestampFormat
+	}
+	if isColored {
+		f.printColored(b, entry, keys, timestampFormat)
+	} else {
+		if !f.DisableTimestamp {
+			f.appendKeyValue(b, "time", entry.Time.Format(timestampFormat))
+		}
+		f.appendKeyValue(b, "level", entry.Level.String())
+		if entry.Message != "" {
+			f.appendKeyValue(b, "msg", entry.Message)
+		}
+		for _, key := range keys {
+			f.appendKeyValue(b, key, entry.Data[key])
+		}
+	}
+
+	b.WriteByte('\n')
+	return b.Bytes(), nil
+}
+
+func (f *TextFormatter) printColored(b *bytes.Buffer, entry *Entry, keys []string, timestampFormat string) {
+	var levelColor int
+	switch entry.Level {
+	case DebugLevel:
+		levelColor = gray
+	case WarnLevel:
+		levelColor = yellow
+	case ErrorLevel, FatalLevel, PanicLevel:
+		levelColor = red
+	default:
+		levelColor = blue
+	}
+
+	levelText := strings.ToUpper(entry.Level.String())[0:4]
+
+	if f.DisableTimestamp {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m %-44s ", levelColor, levelText, entry.Message)
+	} else if !f.FullTimestamp {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%04d] %-44s ", levelColor, levelText, int(entry.Time.Sub(baseTimestamp)/time.Second), entry.Message)
+	} else {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%s] %-44s ", levelColor, levelText, entry.Time.Format(timestampFormat), entry.Message)
+	}
+	for _, k := range keys {
+		v := entry.Data[k]
+		fmt.Fprintf(b, " \x1b[%dm%s\x1b[0m=", levelColor, k)
+		f.appendValue(b, v)
+	}
+}
+
+func (f *TextFormatter) needsQuoting(text string) bool {
+	if f.QuoteEmptyFields && len(text) == 0 {
+		return true
+	}
+	for _, ch := range text {
+		if !((ch >= 'a' && ch <= 'z') ||
+			(ch >= 'A' && ch <= 'Z') ||
+			(ch >= '0' && ch <= '9') ||
+			ch == '-' || ch == '.' || ch == '_' || ch == '/' || ch == '@' || ch == '^' || ch == '+') {
+			return true
+		}
+	}
+	return false
+}
+
+func (f *TextFormatter) appendKeyValue(b *bytes.Buffer, key string, value interface{}) {
+	if b.Len() > 0 {
+		b.WriteByte(' ')
+	}
+	b.WriteString(key)
+	b.WriteByte('=')
+	f.appendValue(b, value)
+}
+
+func (f *TextFormatter) appendValue(b *bytes.Buffer, value interface{}) {
+	stringVal, ok := value.(string)
+	if !ok {
+		stringVal = fmt.Sprint(value)
+	}
+
+	if !f.needsQuoting(stringVal) {
+		b.WriteString(stringVal)
+	} else {
+		b.WriteString(fmt.Sprintf("%q", stringVal))
+	}
+}

go/vendor/github.com/sirupsen/logrus/writer.go

+package logrus
+
+import (
+	"bufio"
+	"io"
+	"runtime"
+)
+
+func (logger *Logger) Writer() *io.PipeWriter {
+	return logger.WriterLevel(InfoLevel)
+}
+
+func (logger *Logger) WriterLevel(level Level) *io.PipeWriter {
+	return NewEntry(logger).WriterLevel(level)
+}
+
+func (entry *Entry) Writer() *io.PipeWriter {
+	return entry.WriterLevel(InfoLevel)
+}
+
+func (entry *Entry) WriterLevel(level Level) *io.PipeWriter {
+	reader, writer := io.Pipe()
+
+	var printFunc func(args ...interface{})
+
+	switch level {
+	case DebugLevel:
+		printFunc = entry.Debug
+	case InfoLevel:
+		printFunc = entry.Info
+	case WarnLevel:
+		printFunc = entry.Warn
+	case ErrorLevel:
+		printFunc = entry.Error
+	case FatalLevel:
+		printFunc = entry.Fatal
+	case PanicLevel:
+		printFunc = entry.Panic
+	default:
+		printFunc = entry.Print
+	}
+
+	go entry.writerScanner(reader, printFunc)
+	runtime.SetFinalizer(writer, writerFinalizer)
+
+	return writer
+}
+
+func (entry *Entry) writerScanner(reader *io.PipeReader, printFunc func(args ...interface{})) {
+	scanner := bufio.NewScanner(reader)
+	for scanner.Scan() {
+		printFunc(scanner.Text())
+	}
+	if err := scanner.Err(); err != nil {
+		entry.Errorf("Error while reading from Writer: %s", err)
+	}
+	reader.Close()
+}
+
+func writerFinalizer(writer *io.PipeWriter) {
+	writer.Close()
+}

go/vendor/golang.org/x/crypto/LICENSE

+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.