pkg: Add logger package from image-builder into pkg folder

rename and adapt it to be usable by composer

pkg/splunk_logger/splunk_hook.go

@@ -0,0 +1,44 @@
+package logger
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/sirupsen/logrus"
+)
+
+type SplunkHook struct {
+	sl *SplunkLogger
+}
+
+func NewSplunkHook(host, port, token, source string) (*SplunkHook, error) {
+	url := fmt.Sprintf("https://%s:%s/services/collector/event", host, port)
+	hostname, err := os.Hostname()
+	if err != nil {
+		return nil, err
+	}
+
+	return &SplunkHook{
+		sl: NewSplunkLogger(url, token, source, hostname),
+	}, nil
+}
+
+func (sh *SplunkHook) Fire(entry *logrus.Entry) error {
+	msg, err := entry.String()
+	if err != nil {
+		return err
+	}
+
+	return sh.sl.LogWithTime(entry.Time, msg)
+}
+
+func (sh *SplunkHook) Levels() []logrus.Level {
+	return []logrus.Level{
+		logrus.PanicLevel,
+		logrus.FatalLevel,
+		logrus.ErrorLevel,
+		logrus.WarnLevel,
+		logrus.InfoLevel,
+		logrus.DebugLevel,
+	}
+}