common/logger/logfmt.go

80 lines
1.4 KiB
Go

package logger
import (
"bytes"
"context"
"log/slog"
"slices"
"strings"
"sync"
)
type logfmt struct {
buf *bytes.Buffer
txt slog.Handler
next slog.Handler
mu sync.Mutex
}
func newLogFmtHandler(next slog.Handler) slog.Handler {
buf := bytes.NewBuffer([]byte{})
h := &logfmt{
buf: buf,
next: next,
txt: slog.NewTextHandler(buf, &slog.HandlerOptions{
ReplaceAttr: func(groups []string, a slog.Attr) slog.Attr {
if a.Key == slog.TimeKey && len(groups) == 0 {
return slog.Attr{}
}
if a.Key == slog.LevelKey && len(groups) == 0 {
return slog.Attr{}
}
return a
},
}),
}
return h
}
func (h *logfmt) Enabled(ctx context.Context, lvl slog.Level) bool {
return h.next.Enabled(ctx, lvl)
}
func (h *logfmt) WithAttrs(attrs []slog.Attr) slog.Handler {
return &logfmt{
buf: bytes.NewBuffer([]byte{}),
next: h.next.WithAttrs(slices.Clone(attrs)),
txt: h.txt.WithAttrs(slices.Clone(attrs)),
}
}
func (h *logfmt) WithGroup(g string) slog.Handler {
if g == "" {
return h
}
return &logfmt{
buf: bytes.NewBuffer([]byte{}),
next: h.next.WithGroup(g),
txt: h.txt.WithGroup(g),
}
}
func (h *logfmt) Handle(ctx context.Context, r slog.Record) error {
h.mu.Lock()
defer h.mu.Unlock()
if h.buf.Len() > 0 {
panic("buffer wasn't empty")
}
h.txt.Handle(ctx, r)
r.Message = h.buf.String()
r.Message = strings.TrimSuffix(r.Message, "\n")
h.buf.Reset()
return h.next.Handle(ctx, r)
}