Update vendor (#1265)

vendor/github.com/mattermost/mattermost-server/v5/mlog/default.go

@@ -4,9 +4,13 @@
 package mlog
 
 import (
+	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"os"
+
+	"github.com/mattermost/logr"
 )
 
 // defaultLog manually encodes the log to STDERR, providing a basic, default logging implementation
@@ -49,3 +53,43 @@ func defaultCriticalLog(msg string, fields ...Field) {
 	// We map critical to error in zap, so be consistent.
 	defaultLog("error", msg, fields...)
 }
+
+func defaultCustomLog(lvl LogLevel, msg string, fields ...Field) {
+	// custom log levels are only output once log targets are configured.
+}
+
+func defaultCustomMultiLog(lvl []LogLevel, msg string, fields ...Field) {
+	// custom log levels are only output once log targets are configured.
+}
+
+func defaultFlush(ctx context.Context) error {
+	return nil
+}
+
+func defaultAdvancedConfig(cfg LogTargetCfg) error {
+	// mlog.ConfigAdvancedConfig should not be called until default
+	// logger is replaced with mlog.Logger instance.
+	return errors.New("cannot config advanced logging on default logger")
+}
+
+func defaultAdvancedShutdown(ctx context.Context) error {
+	return nil
+}
+
+func defaultAddTarget(targets ...logr.Target) error {
+	// mlog.AddTarget should not be called until default
+	// logger is replaced with mlog.Logger instance.
+	return errors.New("cannot AddTarget on default logger")
+}
+
+func defaultRemoveTargets(ctx context.Context, f func(TargetInfo) bool) error {
+	// mlog.RemoveTargets should not be called until default
+	// logger is replaced with mlog.Logger instance.
+	return errors.New("cannot RemoveTargets on default logger")
+}
+
+func defaultEnableMetrics(collector logr.MetricsCollector) error {
+	// mlog.EnableMetrics should not be called until default
+	// logger is replaced with mlog.Logger instance.
+	return errors.New("cannot EnableMetrics on default logger")
+}

vendor/github.com/mattermost/mattermost-server/v5/mlog/errors.go

@@ -0,0 +1,30 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package mlog
+
+import "github.com/mattermost/logr"
+
+// onLoggerError is called when the logging system encounters an error,
+// such as a target not able to write records. The targets will keep trying
+// however the error will be logged with a dedicated level that can be output
+// to a safe/always available target for monitoring or alerting.
+func onLoggerError(err error) {
+	Log(LvlLogError, "advanced logging error", Err(err))
+}
+
+// onQueueFull is called when the main logger queue is full, indicating the
+// volume and frequency of log record creation is too high for the queue size
+// and/or the target latencies.
+func onQueueFull(rec *logr.LogRec, maxQueueSize int) bool {
+	Log(LvlLogError, "main queue full, dropping record", Any("rec", rec))
+	return true // drop record
+}
+
+// onTargetQueueFull is called when the main logger queue is full, indicating the
+// volume and frequency of log record creation is too high for the target's queue size
+// and/or the target latency.
+func onTargetQueueFull(target logr.Target, rec *logr.LogRec, maxQueueSize int) bool {
+	Log(LvlLogError, "target queue full, dropping record", String("target", ""), Any("rec", rec))
+	return true // drop record
+}

vendor/github.com/mattermost/mattermost-server/v5/mlog/global.go

@@ -4,6 +4,11 @@
 package mlog
 
 import (
+	"context"
+	"log"
+	"sync/atomic"
+
+	"github.com/mattermost/logr"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 )
@@ -11,6 +16,10 @@ import (
 var globalLogger *Logger
 
 func InitGlobalLogger(logger *Logger) {
+	// Clean up previous instance.
+	if globalLogger != nil && globalLogger.logrLogger != nil {
+		globalLogger.logrLogger.Logr().Shutdown()
+	}
 	glob := *logger
 	glob.zap = glob.zap.WithOptions(zap.AddCallerSkip(1))
 	globalLogger = &glob
@@ -19,13 +28,46 @@ func InitGlobalLogger(logger *Logger) {
 	Warn = globalLogger.Warn
 	Error = globalLogger.Error
 	Critical = globalLogger.Critical
+	Log = globalLogger.Log
+	LogM = globalLogger.LogM
+	Flush = globalLogger.Flush
+	ConfigAdvancedLogging = globalLogger.ConfigAdvancedLogging
+	ShutdownAdvancedLogging = globalLogger.ShutdownAdvancedLogging
+	AddTarget = globalLogger.AddTarget
+	RemoveTargets = globalLogger.RemoveTargets
+	EnableMetrics = globalLogger.EnableMetrics
+}
+
+// logWriterFunc provides access to mlog via io.Writer, so the standard logger
+// can be redirected to use mlog and whatever targets are defined.
+type logWriterFunc func([]byte) (int, error)
+
+func (lw logWriterFunc) Write(p []byte) (int, error) {
+	return lw(p)
 }
 
 func RedirectStdLog(logger *Logger) {
-	zap.RedirectStdLogAt(logger.zap.With(zap.String("source", "stdlog")).WithOptions(zap.AddCallerSkip(-2)), zapcore.ErrorLevel)
+	if atomic.LoadInt32(&disableZap) == 0 {
+		zap.RedirectStdLogAt(logger.zap.With(zap.String("source", "stdlog")).WithOptions(zap.AddCallerSkip(-2)), zapcore.ErrorLevel)
+		return
+	}
+
+	writer := func(p []byte) (int, error) {
+		Log(LvlStdLog, string(p))
+		return len(p), nil
+	}
+	log.SetOutput(logWriterFunc(writer))
 }
 
 type LogFunc func(string, ...Field)
+type LogFuncCustom func(LogLevel, string, ...Field)
+type LogFuncCustomMulti func([]LogLevel, string, ...Field)
+type FlushFunc func(context.Context) error
+type ConfigFunc func(cfg LogTargetCfg) error
+type ShutdownFunc func(context.Context) error
+type AddTargetFunc func(...logr.Target) error
+type RemoveTargetsFunc func(context.Context, func(TargetInfo) bool) error
+type EnableMetricsFunc func(logr.MetricsCollector) error
 
 // DON'T USE THIS Modify the level on the app logger
 func GloballyDisableDebugLogForTest() {
@@ -42,3 +84,12 @@ var Info LogFunc = defaultInfoLog
 var Warn LogFunc = defaultWarnLog
 var Error LogFunc = defaultErrorLog
 var Critical LogFunc = defaultCriticalLog
+var Log LogFuncCustom = defaultCustomLog
+var LogM LogFuncCustomMulti = defaultCustomMultiLog
+var Flush FlushFunc = defaultFlush
+
+var ConfigAdvancedLogging ConfigFunc = defaultAdvancedConfig
+var ShutdownAdvancedLogging ShutdownFunc = defaultAdvancedShutdown
+var AddTarget AddTargetFunc = defaultAddTarget
+var RemoveTargets RemoveTargetsFunc = defaultRemoveTargets
+var EnableMetrics EnableMetricsFunc = defaultEnableMetrics

vendor/github.com/mattermost/mattermost-server/v5/mlog/levels.go

@@ -0,0 +1,39 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package mlog
+
+// Standard levels
+var (
+	LvlPanic = LogLevel{ID: 0, Name: "panic", Stacktrace: true}
+	LvlFatal = LogLevel{ID: 1, Name: "fatal", Stacktrace: true}
+	LvlError = LogLevel{ID: 2, Name: "error"}
+	LvlWarn  = LogLevel{ID: 3, Name: "warn"}
+	LvlInfo  = LogLevel{ID: 4, Name: "info"}
+	LvlDebug = LogLevel{ID: 5, Name: "debug"}
+	LvlTrace = LogLevel{ID: 6, Name: "trace"}
+	// used by redirected standard logger
+	LvlStdLog = LogLevel{ID: 10, Name: "stdlog"}
+	// used only by the logger
+	LvlLogError = LogLevel{ID: 11, Name: "logerror", Stacktrace: true}
+)
+
+// Register custom (discrete) levels here.
+// !!!!! ID's must not exceed 32,768 !!!!!!
+var (
+	// used by the audit system
+	LvlAuditAPI     = LogLevel{ID: 100, Name: "audit-api"}
+	LvlAuditContent = LogLevel{ID: 101, Name: "audit-content"}
+	LvlAuditPerms   = LogLevel{ID: 102, Name: "audit-permissions"}
+	LvlAuditCLI     = LogLevel{ID: 103, Name: "audit-cli"}
+
+	// used by the TCP log target
+	LvlTcpLogTarget = LogLevel{ID: 120, Name: "TcpLogTarget"}
+
+	// add more here ...
+)
+
+// Combinations for LogM (log multi)
+var (
+	MLvlAuditAll = []LogLevel{LvlAuditAPI, LvlAuditContent, LvlAuditPerms, LvlAuditCLI}
+)

vendor/github.com/mattermost/mattermost-server/v5/mlog/log.go

@@ -4,10 +4,15 @@
 package mlog
 
 import (
+	"context"
+	"fmt"
 	"io"
 	"log"
 	"os"
+	"sync/atomic"
+	"time"
 
+	"github.com/mattermost/logr"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 	"gopkg.in/natefinch/lumberjack.v2"
@@ -22,6 +27,19 @@ const (
 	LevelWarn = "warn"
 	// Errors are messages about things we know are problems
 	LevelError = "error"
+
+	// DefaultFlushTimeout is the default amount of time mlog.Flush will wait
+	// before timing out.
+	DefaultFlushTimeout = time.Second * 5
+)
+
+var (
+	// disableZap is set when Zap should be disabled and Logr used instead.
+	// This is needed for unit testing as Zap has no shutdown capabilities
+	// and holds file handles until process exit. Currently unit test create
+	// many server instances, and thus many Zap log files.
+	// This flag will be removed when Zap is permanently replaced.
+	disableZap int32
 )
 
 // Type and function aliases from zap to limit the libraries scope into MM code
@@ -38,6 +56,8 @@ var NamedErr = zap.NamedError
 var Bool = zap.Bool
 var Duration = zap.Duration
 
+type TargetInfo logr.TargetInfo
+
 type LoggerConfiguration struct {
 	EnableConsole bool
 	ConsoleJson   bool
@@ -52,6 +72,7 @@ type Logger struct {
 	zap          *zap.Logger
 	consoleLevel zap.AtomicLevel
 	fileLevel    zap.AtomicLevel
+	logrLogger   *logr.Logger
 }
 
 func getZapLevel(level string) zapcore.Level {
@@ -84,6 +105,7 @@ func NewLogger(config *LoggerConfiguration) *Logger {
 	logger := &Logger{
 		consoleLevel: zap.NewAtomicLevelAt(getZapLevel(config.ConsoleLevel)),
 		fileLevel:    zap.NewAtomicLevelAt(getZapLevel(config.FileLevel)),
+		logrLogger:   newLogr(),
 	}
 
 	if config.EnableConsole {
@@ -93,13 +115,33 @@ func NewLogger(config *LoggerConfiguration) *Logger {
 	}
 
 	if config.EnableFile {
-		writer := zapcore.AddSync(&lumberjack.Logger{
-			Filename: config.FileLocation,
-			MaxSize:  100,
-			Compress: true,
-		})
-		core := zapcore.NewCore(makeEncoder(config.FileJson), writer, logger.fileLevel)
-		cores = append(cores, core)
+		if atomic.LoadInt32(&disableZap) != 0 {
+			t := &LogTarget{
+				Type:         "file",
+				Format:       "json",
+				Levels:       mlogLevelToLogrLevels(config.FileLevel),
+				MaxQueueSize: DefaultMaxTargetQueue,
+				Options: []byte(fmt.Sprintf(`{"Filename":"%s", "MaxSizeMB":%d, "Compress":%t}`,
+					config.FileLocation, 100, true)),
+			}
+			if !config.FileJson {
+				t.Format = "plain"
+			}
+			if tgt, err := NewLogrTarget("mlogFile", t); err == nil {
+				logger.logrLogger.Logr().AddTarget(tgt)
+			} else {
+				Error("error creating mlogFile", Err(err))
+			}
+		} else {
+			writer := zapcore.AddSync(&lumberjack.Logger{
+				Filename: config.FileLocation,
+				MaxSize:  100,
+				Compress: true,
+			})
+
+			core := zapcore.NewCore(makeEncoder(config.FileJson), writer, logger.fileLevel)
+			cores = append(cores, core)
+		}
 	}
 
 	combinedCore := zapcore.NewTee(cores...)
@@ -107,7 +149,6 @@ func NewLogger(config *LoggerConfiguration) *Logger {
 	logger.zap = zap.New(combinedCore,
 		zap.AddCaller(),
 	)
-
 	return logger
 }
 
@@ -123,6 +164,10 @@ func (l *Logger) SetConsoleLevel(level string) {
 func (l *Logger) With(fields ...Field) *Logger {
 	newlogger := *l
 	newlogger.zap = newlogger.zap.With(fields...)
+	if newlogger.logrLogger != nil {
+		ll := newlogger.logrLogger.WithFields(zapToLogr(fields))
+		newlogger.logrLogger = &ll
+	}
 	return &newlogger
 }
 
@@ -161,20 +206,120 @@ func (l *Logger) Sugar() *SugarLogger {
 
 func (l *Logger) Debug(message string, fields ...Field) {
 	l.zap.Debug(message, fields...)
+	if isLevelEnabled(l.logrLogger, logr.Debug) {
+		l.logrLogger.WithFields(zapToLogr(fields)).Debug(message)
+	}
 }
 
 func (l *Logger) Info(message string, fields ...Field) {
 	l.zap.Info(message, fields...)
+	if isLevelEnabled(l.logrLogger, logr.Info) {
+		l.logrLogger.WithFields(zapToLogr(fields)).Info(message)
+	}
 }
 
 func (l *Logger) Warn(message string, fields ...Field) {
 	l.zap.Warn(message, fields...)
+	if isLevelEnabled(l.logrLogger, logr.Warn) {
+		l.logrLogger.WithFields(zapToLogr(fields)).Warn(message)
+	}
 }
 
 func (l *Logger) Error(message string, fields ...Field) {
 	l.zap.Error(message, fields...)
+	if isLevelEnabled(l.logrLogger, logr.Error) {
+		l.logrLogger.WithFields(zapToLogr(fields)).Error(message)
+	}
 }
 
 func (l *Logger) Critical(message string, fields ...Field) {
 	l.zap.Error(message, fields...)
+	if isLevelEnabled(l.logrLogger, logr.Error) {
+		l.logrLogger.WithFields(zapToLogr(fields)).Error(message)
+	}
+}
+
+func (l *Logger) Log(level LogLevel, message string, fields ...Field) {
+	l.logrLogger.WithFields(zapToLogr(fields)).Log(logr.Level(level), message)
+}
+
+func (l *Logger) LogM(levels []LogLevel, message string, fields ...Field) {
+	var logger *logr.Logger
+	for _, lvl := range levels {
+		if isLevelEnabled(l.logrLogger, logr.Level(lvl)) {
+			// don't create logger with fields unless at least one level is active.
+			if logger == nil {
+				l := l.logrLogger.WithFields(zapToLogr(fields))
+				logger = &l
+			}
+			logger.Log(logr.Level(lvl), message)
+		}
+	}
+}
+
+func (l *Logger) Flush(cxt context.Context) error {
+	return l.logrLogger.Logr().FlushWithTimeout(cxt)
+}
+
+// ShutdownAdvancedLogging stops the logger from accepting new log records and tries to
+// flush queues within the context timeout. Once complete all targets are shutdown
+// and any resources released.
+func (l *Logger) ShutdownAdvancedLogging(cxt context.Context) error {
+	err := l.logrLogger.Logr().ShutdownWithTimeout(cxt)
+	l.logrLogger = newLogr()
+	return err
+}
+
+// ConfigAdvancedLoggingConfig (re)configures advanced logging based on the
+// specified log targets. This is the easiest way to get the advanced logger
+// configured via a config source such as file.
+func (l *Logger) ConfigAdvancedLogging(targets LogTargetCfg) error {
+	if err := l.ShutdownAdvancedLogging(context.Background()); err != nil {
+		Error("error shutting down previous logger", Err(err))
+	}
+
+	err := logrAddTargets(l.logrLogger, targets)
+	return err
+}
+
+// AddTarget adds one or more logr.Target to the advanced logger. This is the preferred method
+// to add custom targets or provide configuration that cannot be expressed via a
+// config source.
+func (l *Logger) AddTarget(targets ...logr.Target) error {
+	return l.logrLogger.Logr().AddTarget(targets...)
+}
+
+// RemoveTargets selectively removes targets that were previously added to this logger instance
+// using the passed in filter function. The filter function should return true to remove the target
+// and false to keep it.
+func (l *Logger) RemoveTargets(ctx context.Context, f func(ti TargetInfo) bool) error {
+	// Use locally defined TargetInfo type so we don't spread Logr dependencies.
+	fc := func(tic logr.TargetInfo) bool {
+		return f(TargetInfo(tic))
+	}
+	return l.logrLogger.Logr().RemoveTargets(ctx, fc)
+}
+
+// EnableMetrics enables metrics collection by supplying a MetricsCollector.
+// The MetricsCollector provides counters and gauges that are updated by log targets.
+func (l *Logger) EnableMetrics(collector logr.MetricsCollector) error {
+	return l.logrLogger.Logr().SetMetricsCollector(collector)
+}
+
+// DisableZap is called to disable Zap, and Logr will be used instead. Any Logger
+// instances created after this call will only use Logr.
+//
+// This is needed for unit testing as Zap has no shutdown capabilities
+// and holds file handles until process exit. Currently unit tests create
+// many server instances, and thus many Zap log file handles.
+//
+// This method will be removed when Zap is permanently replaced.
+func DisableZap() {
+	atomic.StoreInt32(&disableZap, 1)
+}
+
+// EnableZap re-enables Zap such that any Logger instances created after this
+// call will allow Zap targets.
+func EnableZap() {
+	atomic.StoreInt32(&disableZap, 0)
 }

vendor/github.com/mattermost/mattermost-server/v5/mlog/logr.go

@@ -0,0 +1,247 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package mlog
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/hashicorp/go-multierror"
+	"github.com/mattermost/logr"
+	logrFmt "github.com/mattermost/logr/format"
+	"github.com/mattermost/logr/target"
+	"go.uber.org/zap/zapcore"
+)
+
+const (
+	DefaultMaxTargetQueue = 1000
+	DefaultSysLogPort     = 514
+)
+
+type LogLevel struct {
+	ID         logr.LevelID
+	Name       string
+	Stacktrace bool
+}
+
+type LogTarget struct {
+	Type         string // one of "console", "file", "tcp", "syslog", "none".
+	Format       string // one of "json", "plain"
+	Levels       []LogLevel
+	Options      json.RawMessage
+	MaxQueueSize int
+}
+
+type LogTargetCfg map[string]*LogTarget
+type LogrCleanup func() error
+
+func newLogr() *logr.Logger {
+	lgr := &logr.Logr{}
+	lgr.OnExit = func(int) {}
+	lgr.OnPanic = func(interface{}) {}
+	lgr.OnLoggerError = onLoggerError
+	lgr.OnQueueFull = onQueueFull
+	lgr.OnTargetQueueFull = onTargetQueueFull
+
+	logger := lgr.NewLogger()
+	return &logger
+}
+
+func logrAddTargets(logger *logr.Logger, targets LogTargetCfg) error {
+	lgr := logger.Logr()
+	var errs error
+	for name, t := range targets {
+		target, err := NewLogrTarget(name, t)
+		if err != nil {
+			errs = multierror.Append(err)
+			continue
+		}
+		if target != nil {
+			target.SetName(name)
+			lgr.AddTarget(target)
+		}
+	}
+	return errs
+}
+
+// NewLogrTarget creates a `logr.Target` based on a target config.
+// Can be used when parsing custom config files, or when programmatically adding
+// built-in targets. Use `mlog.AddTarget` to add custom targets.
+func NewLogrTarget(name string, t *LogTarget) (logr.Target, error) {
+	formatter, err := newFormatter(name, t.Format)
+	if err != nil {
+		return nil, err
+	}
+	filter, err := newFilter(name, t.Levels)
+	if err != nil {
+		return nil, err
+	}
+
+	if t.MaxQueueSize == 0 {
+		t.MaxQueueSize = DefaultMaxTargetQueue
+	}
+
+	switch t.Type {
+	case "console":
+		return newConsoleTarget(name, t, filter, formatter)
+	case "file":
+		return newFileTarget(name, t, filter, formatter)
+	case "syslog":
+		return newSyslogTarget(name, t, filter, formatter)
+	case "tcp":
+		return newTCPTarget(name, t, filter, formatter)
+	case "none":
+		return nil, nil
+	}
+	return nil, fmt.Errorf("invalid type '%s' for target %s", t.Type, name)
+}
+
+func newFilter(name string, levels []LogLevel) (logr.Filter, error) {
+	filter := &logr.CustomFilter{}
+	for _, lvl := range levels {
+		filter.Add(logr.Level(lvl))
+	}
+	return filter, nil
+}
+
+func newFormatter(name string, format string) (logr.Formatter, error) {
+	switch format {
+	case "json", "":
+		return &logrFmt.JSON{}, nil
+	case "plain":
+		return &logrFmt.Plain{Delim: " | "}, nil
+	default:
+		return nil, fmt.Errorf("invalid format '%s' for target %s", format, name)
+	}
+}
+
+func newConsoleTarget(name string, t *LogTarget, filter logr.Filter, formatter logr.Formatter) (logr.Target, error) {
+	type consoleOptions struct {
+		Out string `json:"Out"`
+	}
+	options := &consoleOptions{}
+	if err := json.Unmarshal(t.Options, options); err != nil {
+		return nil, err
+	}
+
+	var w io.Writer
+	switch options.Out {
+	case "stdout", "":
+		w = os.Stdout
+	case "stderr":
+		w = os.Stderr
+	default:
+		return nil, fmt.Errorf("invalid out '%s' for target %s", options.Out, name)
+	}
+
+	newTarget := target.NewWriterTarget(filter, formatter, w, t.MaxQueueSize)
+	return newTarget, nil
+}
+
+func newFileTarget(name string, t *LogTarget, filter logr.Filter, formatter logr.Formatter) (logr.Target, error) {
+	type fileOptions struct {
+		Filename   string `json:"Filename"`
+		MaxSize    int    `json:"MaxSizeMB"`
+		MaxAge     int    `json:"MaxAgeDays"`
+		MaxBackups int    `json:"MaxBackups"`
+		Compress   bool   `json:"Compress"`
+	}
+	options := &fileOptions{}
+	if err := json.Unmarshal(t.Options, options); err != nil {
+		return nil, err
+	}
+	return newFileTargetWithOpts(name, t, target.FileOptions(*options), filter, formatter)
+}
+
+func newFileTargetWithOpts(name string, t *LogTarget, opts target.FileOptions, filter logr.Filter, formatter logr.Formatter) (logr.Target, error) {
+	if opts.Filename == "" {
+		return nil, fmt.Errorf("missing 'Filename' option for target %s", name)
+	}
+	if err := checkFileWritable(opts.Filename); err != nil {
+		return nil, fmt.Errorf("error writing to 'Filename' for target %s: %w", name, err)
+	}
+
+	newTarget := target.NewFileTarget(filter, formatter, opts, t.MaxQueueSize)
+	return newTarget, nil
+}
+
+func newSyslogTarget(name string, t *LogTarget, filter logr.Filter, formatter logr.Formatter) (logr.Target, error) {
+	options := &SyslogParams{}
+	if err := json.Unmarshal(t.Options, options); err != nil {
+		return nil, err
+	}
+
+	if options.IP == "" {
+		return nil, fmt.Errorf("missing 'IP' option for target %s", name)
+	}
+	if options.Port == 0 {
+		options.Port = DefaultSysLogPort
+	}
+	return NewSyslogTarget(filter, formatter, options, t.MaxQueueSize)
+}
+
+func newTCPTarget(name string, t *LogTarget, filter logr.Filter, formatter logr.Formatter) (logr.Target, error) {
+	options := &TcpParams{}
+	if err := json.Unmarshal(t.Options, options); err != nil {
+		return nil, err
+	}
+
+	if options.IP == "" {
+		return nil, fmt.Errorf("missing 'IP' option for target %s", name)
+	}
+	if options.Port == 0 {
+		return nil, fmt.Errorf("missing 'Port' option for target %s", name)
+	}
+	return NewTcpTarget(filter, formatter, options, t.MaxQueueSize)
+}
+
+func checkFileWritable(filename string) error {
+	// try opening/creating the file for writing
+	file, err := os.OpenFile(filename, os.O_RDWR|os.O_APPEND|os.O_CREATE, 0600)
+	if err != nil {
+		return err
+	}
+	file.Close()
+	return nil
+}
+
+func isLevelEnabled(logger *logr.Logger, level logr.Level) bool {
+	if logger == nil || logger.Logr() == nil {
+		return false
+	}
+
+	status := logger.Logr().IsLevelEnabled(level)
+	return status.Enabled
+}
+
+// zapToLogr converts Zap fields to Logr fields.
+// This will not be needed once Logr is used for all logging.
+func zapToLogr(zapFields []Field) logr.Fields {
+	encoder := zapcore.NewMapObjectEncoder()
+	for _, zapField := range zapFields {
+		zapField.AddTo(encoder)
+	}
+	return logr.Fields(encoder.Fields)
+}
+
+// mlogLevelToLogrLevel converts a mlog logger level to
+// an array of discrete Logr levels.
+func mlogLevelToLogrLevels(level string) []LogLevel {
+	levels := make([]LogLevel, 0)
+	levels = append(levels, LvlError, LvlPanic, LvlFatal, LvlStdLog)
+
+	switch level {
+	case LevelDebug:
+		levels = append(levels, LvlDebug)
+		fallthrough
+	case LevelInfo:
+		levels = append(levels, LvlInfo)
+		fallthrough
+	case LevelWarn:
+		levels = append(levels, LvlWarn)
+	}
+	return levels
+}

vendor/github.com/mattermost/mattermost-server/v5/mlog/syslog.go

@@ -0,0 +1,142 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package mlog
+
+import (
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"io/ioutil"
+
+	"github.com/mattermost/logr"
+	"github.com/wiggin77/merror"
+	syslog "github.com/wiggin77/srslog"
+)
+
+// Syslog outputs log records to local or remote syslog.
+type Syslog struct {
+	logr.Basic
+	w *syslog.Writer
+}
+
+// SyslogParams provides parameters for dialing a syslog daemon.
+type SyslogParams struct {
+	IP       string `json:"IP"`
+	Port     int    `json:"Port"`
+	Tag      string `json:"Tag"`
+	TLS      bool   `json:"TLS"`
+	Cert     string `json:"Cert"`
+	Insecure bool   `json:"Insecure"`
+}
+
+// NewSyslogTarget creates a target capable of outputting log records to remote or local syslog, with or without TLS.
+func NewSyslogTarget(filter logr.Filter, formatter logr.Formatter, params *SyslogParams, maxQueue int) (*Syslog, error) {
+	network := "tcp"
+	var config *tls.Config
+
+	if params.TLS {
+		network = "tcp+tls"
+		config = &tls.Config{InsecureSkipVerify: params.Insecure}
+		if params.Cert != "" {
+			pool, err := getCertPool(params.Cert)
+			if err != nil {
+				return nil, err
+			}
+			config.RootCAs = pool
+		}
+	}
+	raddr := fmt.Sprintf("%s:%d", params.IP, params.Port)
+
+	writer, err := syslog.DialWithTLSConfig(network, raddr, syslog.LOG_INFO, params.Tag, config)
+	if err != nil {
+		return nil, err
+	}
+
+	s := &Syslog{w: writer}
+	s.Basic.Start(s, s, filter, formatter, maxQueue)
+
+	return s, nil
+}
+
+// Shutdown stops processing log records after making best effort to flush queue.
+func (s *Syslog) Shutdown(ctx context.Context) error {
+	errs := merror.New()
+
+	err := s.Basic.Shutdown(ctx)
+	errs.Append(err)
+
+	err = s.w.Close()
+	errs.Append(err)
+
+	return errs.ErrorOrNil()
+}
+
+// getCertPool returns a x509.CertPool containing the cert(s)
+// from `cert`, which can be a path to a .pem or .crt file,
+// or a base64 encoded cert.
+func getCertPool(cert string) (*x509.CertPool, error) {
+	if cert == "" {
+		return nil, errors.New("no cert provided")
+	}
+
+	// first treat as a file and try to read.
+	serverCert, err := ioutil.ReadFile(cert)
+	if err != nil {
+		// maybe it's a base64 encoded cert
+		serverCert, err = base64.StdEncoding.DecodeString(cert)
+		if err != nil {
+			return nil, errors.New("cert cannot be read")
+		}
+	}
+
+	pool := x509.NewCertPool()
+	if ok := pool.AppendCertsFromPEM(serverCert); ok {
+		return pool, nil
+	}
+	return nil, errors.New("cannot parse cert")
+}
+
+// Write converts the log record to bytes, via the Formatter,
+// and outputs to syslog.
+func (s *Syslog) Write(rec *logr.LogRec) error {
+	_, stacktrace := s.IsLevelEnabled(rec.Level())
+
+	buf := rec.Logger().Logr().BorrowBuffer()
+	defer rec.Logger().Logr().ReleaseBuffer(buf)
+
+	buf, err := s.Formatter().Format(rec, stacktrace, buf)
+	if err != nil {
+		return err
+	}
+	txt := buf.String()
+
+	switch rec.Level() {
+	case logr.Panic, logr.Fatal:
+		err = s.w.Crit(txt)
+	case logr.Error:
+		err = s.w.Err(txt)
+	case logr.Warn:
+		err = s.w.Warning(txt)
+	case logr.Debug, logr.Trace:
+		err = s.w.Debug(txt)
+	default:
+		// logr.Info plus all custom levels.
+		err = s.w.Info(txt)
+	}
+
+	if err != nil {
+		reporter := rec.Logger().Logr().ReportError
+		reporter(fmt.Errorf("syslog write fail: %w", err))
+		// syslog writer will try to reconnect.
+	}
+	return err
+}
+
+// String returns a string representation of this target.
+func (s *Syslog) String() string {
+	return "SyslogTarget"
+}

vendor/github.com/mattermost/mattermost-server/v5/mlog/tcp.go

@@ -0,0 +1,274 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package mlog
+
+import (
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"sync"
+	"time"
+
+	"github.com/hashicorp/go-multierror"
+	"github.com/mattermost/logr"
+
+	_ "net/http/pprof"
+)
+
+const (
+	DialTimeoutSecs             = 30
+	WriteTimeoutSecs            = 30
+	RetryBackoffMillis    int64 = 100
+	MaxRetryBackoffMillis int64 = 30 * 1000 // 30 seconds
+)
+
+// Tcp outputs log records to raw socket server.
+type Tcp struct {
+	logr.Basic
+
+	params *TcpParams
+	addy   string
+
+	mutex    sync.Mutex
+	conn     net.Conn
+	monitor  chan struct{}
+	shutdown chan struct{}
+}
+
+// TcpParams provides parameters for dialing a socket server.
+type TcpParams struct {
+	IP       string `json:"IP"`
+	Port     int    `json:"Port"`
+	TLS      bool   `json:"TLS"`
+	Cert     string `json:"Cert"`
+	Insecure bool   `json:"Insecure"`
+}
+
+// NewTcpTarget creates a target capable of outputting log records to a raw socket, with or without TLS.
+func NewTcpTarget(filter logr.Filter, formatter logr.Formatter, params *TcpParams, maxQueue int) (*Tcp, error) {
+	tcp := &Tcp{
+		params:   params,
+		addy:     fmt.Sprintf("%s:%d", params.IP, params.Port),
+		monitor:  make(chan struct{}),
+		shutdown: make(chan struct{}),
+	}
+	tcp.Basic.Start(tcp, tcp, filter, formatter, maxQueue)
+
+	return tcp, nil
+}
+
+// getConn provides a net.Conn.  If a connection already exists, it is returned immediately,
+// otherwise this method blocks until a new connection is created, timeout or shutdown.
+func (tcp *Tcp) getConn() (net.Conn, error) {
+	tcp.mutex.Lock()
+	defer tcp.mutex.Unlock()
+
+	Log(LvlTcpLogTarget, "getConn enter", String("addy", tcp.addy))
+	defer Log(LvlTcpLogTarget, "getConn exit", String("addy", tcp.addy))
+
+	if tcp.conn != nil {
+		Log(LvlTcpLogTarget, "reusing existing conn", String("addy", tcp.addy)) // use "With" once Zap is removed
+		return tcp.conn, nil
+	}
+
+	type result struct {
+		conn net.Conn
+		err  error
+	}
+
+	connChan := make(chan result)
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*DialTimeoutSecs)
+	defer cancel()
+
+	go func(ctx context.Context, ch chan result) {
+		Log(LvlTcpLogTarget, "dailing", String("addy", tcp.addy))
+		conn, err := tcp.dial(ctx)
+		if err == nil {
+			tcp.conn = conn
+			tcp.monitor = make(chan struct{})
+			go monitor(tcp.conn, tcp.monitor)
+		}
+		connChan <- result{conn: conn, err: err}
+	}(ctx, connChan)
+
+	select {
+	case <-tcp.shutdown:
+		return nil, errors.New("shutdown")
+	case res := <-connChan:
+		return res.conn, res.err
+	}
+}
+
+// dial connects to a TCP socket, and optionally performs a TLS handshake.
+// A non-nil context must be provided which can cancel the dial.
+func (tcp *Tcp) dial(ctx context.Context) (net.Conn, error) {
+	var dialer net.Dialer
+	dialer.Timeout = time.Second * DialTimeoutSecs
+	conn, err := dialer.DialContext(ctx, "tcp", fmt.Sprintf("%s:%d", tcp.params.IP, tcp.params.Port))
+	if err != nil {
+		return nil, err
+	}
+
+	if !tcp.params.TLS {
+		return conn, nil
+	}
+
+	Log(LvlTcpLogTarget, "TLS handshake", String("addy", tcp.addy))
+
+	tlsconfig := &tls.Config{
+		ServerName:         tcp.params.IP,
+		InsecureSkipVerify: tcp.params.Insecure,
+	}
+	if tcp.params.Cert != "" {
+		pool, err := getCertPool(tcp.params.Cert)
+		if err != nil {
+			return nil, err
+		}
+		tlsconfig.RootCAs = pool
+	}
+
+	tlsConn := tls.Client(conn, tlsconfig)
+	if err := tlsConn.Handshake(); err != nil {
+		return nil, err
+	}
+	return tlsConn, nil
+}
+
+func (tcp *Tcp) close() error {
+	tcp.mutex.Lock()
+	defer tcp.mutex.Unlock()
+
+	var err error
+	if tcp.conn != nil {
+		Log(LvlTcpLogTarget, "closing connection", String("addy", tcp.addy))
+		close(tcp.monitor)
+		err = tcp.conn.Close()
+		tcp.conn = nil
+	}
+	return err
+}
+
+// Shutdown stops processing log records after making best effort to flush queue.
+func (tcp *Tcp) Shutdown(ctx context.Context) error {
+	errs := &multierror.Error{}
+
+	Log(LvlTcpLogTarget, "shutting down", String("addy", tcp.addy))
+
+	if err := tcp.Basic.Shutdown(ctx); err != nil {
+		errs = multierror.Append(errs, err)
+	}
+
+	if err := tcp.close(); err != nil {
+		errs = multierror.Append(errs, err)
+	}
+
+	close(tcp.shutdown)
+	return errs.ErrorOrNil()
+}
+
+// Write converts the log record to bytes, via the Formatter, and outputs to the socket.
+// Called by dedicated target goroutine and will block until success or shutdown.
+func (tcp *Tcp) Write(rec *logr.LogRec) error {
+	_, stacktrace := tcp.IsLevelEnabled(rec.Level())
+
+	buf := rec.Logger().Logr().BorrowBuffer()
+	defer rec.Logger().Logr().ReleaseBuffer(buf)
+
+	buf, err := tcp.Formatter().Format(rec, stacktrace, buf)
+	if err != nil {
+		return err
+	}
+
+	try := 1
+	backoff := RetryBackoffMillis
+	for {
+		select {
+		case <-tcp.shutdown:
+			return err
+		default:
+		}
+
+		conn, err := tcp.getConn()
+		if err != nil {
+			Log(LvlTcpLogTarget, "failed getting connection", String("addy", tcp.addy), Err(err))
+			reporter := rec.Logger().Logr().ReportError
+			reporter(fmt.Errorf("log target %s connection error: %w", tcp.String(), err))
+			backoff = tcp.sleep(backoff)
+			continue
+		}
+
+		conn.SetWriteDeadline(time.Now().Add(time.Second * WriteTimeoutSecs))
+		_, err = buf.WriteTo(conn)
+		if err == nil {
+			return nil
+		}
+
+		Log(LvlTcpLogTarget, "write error", String("addy", tcp.addy), Err(err))
+		reporter := rec.Logger().Logr().ReportError
+		reporter(fmt.Errorf("log target %s write error: %w", tcp.String(), err))
+
+		_ = tcp.close()
+
+		backoff = tcp.sleep(backoff)
+		try++
+		Log(LvlTcpLogTarget, "retrying write", String("addy", tcp.addy), Int("try", try))
+	}
+}
+
+// monitor continuously tries to read from the connection to detect socket close.
+// This is needed because TCP target uses a write only socket and Linux systems
+// take a long time to detect a loss of connectivity on a socket when only writing;
+// the writes simply fail without an error returned.
+func monitor(conn net.Conn, done <-chan struct{}) {
+	addy := conn.RemoteAddr().String()
+	defer Log(LvlTcpLogTarget, "monitor exiting", String("addy", addy))
+
+	buf := make([]byte, 1)
+	for {
+		Log(LvlTcpLogTarget, "monitor loop", String("addy", addy))
+
+		select {
+		case <-done:
+			return
+		case <-time.After(1 * time.Second):
+		}
+
+		err := conn.SetReadDeadline(time.Now().Add(time.Second * 30))
+		if err != nil {
+			continue
+		}
+
+		_, err = conn.Read(buf)
+
+		if errt, ok := err.(net.Error); ok && errt.Timeout() {
+			// read timeout is expected, keep looping.
+			continue
+		}
+
+		// Any other error closes the connection, forcing a reconnect.
+		Log(LvlTcpLogTarget, "monitor closing connection", Err(err))
+		conn.Close()
+		return
+	}
+}
+
+// String returns a string representation of this target.
+func (tcp *Tcp) String() string {
+	return fmt.Sprintf("TcpTarget[%s:%d]", tcp.params.IP, tcp.params.Port)
+}
+
+func (tcp *Tcp) sleep(backoff int64) int64 {
+	select {
+	case <-tcp.shutdown:
+	case <-time.After(time.Millisecond * time.Duration(backoff)):
+	}
+
+	nextBackoff := backoff + (backoff >> 1)
+	if nextBackoff > MaxRetryBackoffMillis {
+		nextBackoff = MaxRetryBackoffMillis
+	}
+	return nextBackoff
+}

vendor/github.com/mattermost/mattermost-server/v5/mlog/test-tls-client-cert.pem

@@ -0,0 +1,43 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE----- 
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

vendor/github.com/mattermost/mattermost-server/v5/mlog/testing.go

@@ -32,9 +32,10 @@ func NewTestingLogger(tb testing.TB, writer io.Writer) *Logger {
 	testingLogger := &Logger{
 		consoleLevel: zap.NewAtomicLevelAt(getZapLevel("debug")),
 		fileLevel:    zap.NewAtomicLevelAt(getZapLevel("info")),
+		logrLogger:   newLogr(),
 	}
 
-	logWriterCore := zapcore.NewCore(makeEncoder(true), logWriterSync, testingLogger.consoleLevel)
+	logWriterCore := zapcore.NewCore(makeEncoder(true), zapcore.Lock(logWriterSync), testingLogger.consoleLevel)
 
 	testingLogger.zap = zap.New(logWriterCore,
 		zap.AddCaller(),