Update vendor (#1265)

vendor/github.com/mattermost/logr/target/syslog.go

@@ -0,0 +1,89 @@
+// +build !windows,!nacl,!plan9
+
+package target
+
+import (
+	"context"
+	"fmt"
+	"log/syslog"
+
+	"github.com/mattermost/logr"
+	"github.com/wiggin77/merror"
+)
+
+// 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 {
+	Network  string
+	Raddr    string
+	Priority syslog.Priority
+	Tag      string
+}
+
+// NewSyslogTarget creates a target capable of outputting log records to remote or local syslog.
+func NewSyslogTarget(filter logr.Filter, formatter logr.Formatter, params *SyslogParams, maxQueue int) (*Syslog, error) {
+	writer, err := syslog.Dial(params.Network, params.Raddr, params.Priority, params.Tag)
+	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()
+}
+
+// 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
+}