root: filter out useless debug logs from vendored packages

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

util/logutil/filter.go

@@ -0,0 +1,36 @@
+package logutil
+
+import (
+	"io/ioutil"
+	"strings"
+
+	"github.com/sirupsen/logrus"
+)
+
+func NewFilter(filters ...string) logrus.Hook {
+	dl := logrus.New()
+	dl.SetOutput(ioutil.Discard)
+	return &logsFilter{
+		filters:       filters,
+		discardLogger: dl,
+	}
+}
+
+type logsFilter struct {
+	filters       []string
+	discardLogger *logrus.Logger
+}
+
+func (d *logsFilter) Levels() []logrus.Level {
+	return []logrus.Level{logrus.DebugLevel}
+}
+
+func (d *logsFilter) Fire(entry *logrus.Entry) error {
+	for _, f := range d.filters {
+		if strings.Contains(entry.Message, f) {
+			entry.Logger = d.discardLogger
+			return nil
+		}
+	}
+	return nil
+}