Update vendor (#1265)

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

@@ -0,0 +1,87 @@
+package target
+
+import (
+	"context"
+	"io"
+
+	"github.com/mattermost/logr"
+	"github.com/wiggin77/merror"
+	"gopkg.in/natefinch/lumberjack.v2"
+)
+
+type FileOptions struct {
+	// Filename is the file to write logs to.  Backup log files will be retained
+	// in the same directory.  It uses <processname>-lumberjack.log in
+	// os.TempDir() if empty.
+	Filename string
+
+	// MaxSize is the maximum size in megabytes of the log file before it gets
+	// rotated. It defaults to 100 megabytes.
+	MaxSize int
+
+	// MaxAge is the maximum number of days to retain old log files based on the
+	// timestamp encoded in their filename.  Note that a day is defined as 24
+	// hours and may not exactly correspond to calendar days due to daylight
+	// savings, leap seconds, etc. The default is not to remove old log files
+	// based on age.
+	MaxAge int
+
+	// MaxBackups is the maximum number of old log files to retain.  The default
+	// is to retain all old log files (though MaxAge may still cause them to get
+	// deleted.)
+	MaxBackups int
+
+	// Compress determines if the rotated log files should be compressed
+	// using gzip. The default is not to perform compression.
+	Compress bool
+}
+
+// File outputs log records to a file which can be log rotated based on size or age.
+// Uses `https://github.com/natefinch/lumberjack` for rotation.
+type File struct {
+	logr.Basic
+	out io.WriteCloser
+}
+
+// NewFileTarget creates a target capable of outputting log records to a rotated file.
+func NewFileTarget(filter logr.Filter, formatter logr.Formatter, opts FileOptions, maxQueue int) *File {
+	lumber := &lumberjack.Logger{
+		Filename:   opts.Filename,
+		MaxSize:    opts.MaxSize,
+		MaxBackups: opts.MaxBackups,
+		MaxAge:     opts.MaxAge,
+		Compress:   opts.Compress,
+	}
+	f := &File{out: lumber}
+	f.Basic.Start(f, f, filter, formatter, maxQueue)
+	return f
+}
+
+// Write converts the log record to bytes, via the Formatter,
+// and outputs to a file.
+func (f *File) Write(rec *logr.LogRec) error {
+	_, stacktrace := f.IsLevelEnabled(rec.Level())
+
+	buf := rec.Logger().Logr().BorrowBuffer()
+	defer rec.Logger().Logr().ReleaseBuffer(buf)
+
+	buf, err := f.Formatter().Format(rec, stacktrace, buf)
+	if err != nil {
+		return err
+	}
+	_, err = f.out.Write(buf.Bytes())
+	return err
+}
+
+// Shutdown flushes any remaining log records and closes the file.
+func (f *File) Shutdown(ctx context.Context) error {
+	errs := merror.New()
+
+	err := f.Basic.Shutdown(ctx)
+	errs.Append(err)
+
+	err = f.out.Close()
+	errs.Append(err)
+
+	return errs.ErrorOrNil()
+}