Add slog sink

pkg/util/logutil/logutil.go

@@ -0,0 +1,52 @@
+// Copyright 2023 Hedgehog
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"bufio"
+	"context"
+	"io"
+)
+
+func NewSink(ctx context.Context, log func(msg string, args ...any), msgPrefix string, args ...any) io.Writer {
+	r, w := io.Pipe()
+
+	go func() {
+		lines := make(chan string)
+		defer close(lines)
+
+		go func() {
+			defer func() {
+				recover() //nolint: errcheck
+			}()
+
+			s := bufio.NewScanner(r)
+			for s.Scan() {
+				lines <- s.Text()
+			}
+		}()
+
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case line := <-lines:
+				log(msgPrefix+line, args...)
+			}
+		}
+	}()
+
+	return w
+}