Import code, preparing for release

log.go

@@ -0,0 +1,29 @@
+package ctrld
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"github.com/rs/zerolog"
+)
+
+// ProxyLog emits the log record for proxy operations.
+// The caller should set it only once.
+var ProxyLog = zerolog.New(io.Discard)
+
+// ReqIdCtxKey is the context.Context key for a request id.
+type ReqIdCtxKey struct{}
+
+// Log emits the logs for a particular zerolog event.
+// The request id associated with the context will be included if presents.
+func Log(ctx context.Context, e *zerolog.Event, format string, v ...any) {
+	id, ok := ctx.Value(ReqIdCtxKey{}).(string)
+	if !ok {
+		e.Msgf(format, v...)
+		return
+	}
+	e.MsgFunc(func() string {
+		return fmt.Sprintf("[%s] %s", id, fmt.Sprintf(format, v...))
+	})
+}