init: first steps

modules/log/formatter.go

@@ -0,0 +1,28 @@
+package log
+
+import (
+	"fmt"
+
+	"github.com/sirupsen/logrus"
+)
+
+type TextFormatter struct {
+	logrusFormatter logrus.TextFormatter
+	prefix          []byte
+}
+
+func NewTextFormatter(prefix string) *TextFormatter {
+	return &TextFormatter{
+		logrusFormatter: logrus.TextFormatter{},
+		prefix:          []byte(fmt.Sprintf("[%s] ", prefix)),
+	}
+}
+
+func (t *TextFormatter) Format(item *logrus.Entry) ([]byte, error) {
+	original, err := t.logrusFormatter.Format(item)
+	if err != nil {
+		return nil, err
+	}
+
+	return append(t.prefix, original...), nil
+}