Move code to pkg

pkg/middlewares/accesslog/logger_formatters.go

@@ -0,0 +1,83 @@
+package accesslog
+
+import (
+	"bytes"
+	"fmt"
+	"time"
+
+	"github.com/sirupsen/logrus"
+)
+
+// default format for time presentation.
+const (
+	commonLogTimeFormat = "02/Jan/2006:15:04:05 -0700"
+	defaultValue        = "-"
+)
+
+// CommonLogFormatter provides formatting in the Traefik common log format.
+type CommonLogFormatter struct{}
+
+// Format formats the log entry in the Traefik common log format.
+func (f *CommonLogFormatter) Format(entry *logrus.Entry) ([]byte, error) {
+	b := &bytes.Buffer{}
+
+	var timestamp = defaultValue
+	if v, ok := entry.Data[StartUTC]; ok {
+		timestamp = v.(time.Time).Format(commonLogTimeFormat)
+	}
+
+	var elapsedMillis int64
+	if v, ok := entry.Data[Duration]; ok {
+		elapsedMillis = v.(time.Duration).Nanoseconds() / 1000000
+	}
+
+	_, err := fmt.Fprintf(b, "%s - %s [%s] \"%s %s %s\" %v %v %s %s %v %s %s %dms\n",
+		toLog(entry.Data, ClientHost, defaultValue, false),
+		toLog(entry.Data, ClientUsername, defaultValue, false),
+		timestamp,
+		toLog(entry.Data, RequestMethod, defaultValue, false),
+		toLog(entry.Data, RequestPath, defaultValue, false),
+		toLog(entry.Data, RequestProtocol, defaultValue, false),
+		toLog(entry.Data, OriginStatus, defaultValue, true),
+		toLog(entry.Data, OriginContentSize, defaultValue, true),
+		toLog(entry.Data, "request_Referer", `"-"`, true),
+		toLog(entry.Data, "request_User-Agent", `"-"`, true),
+		toLog(entry.Data, RequestCount, defaultValue, true),
+		toLog(entry.Data, RouterName, defaultValue, true),
+		toLog(entry.Data, ServiceURL, defaultValue, true),
+		elapsedMillis)
+
+	return b.Bytes(), err
+}
+
+func toLog(fields logrus.Fields, key string, defaultValue string, quoted bool) interface{} {
+	if v, ok := fields[key]; ok {
+		if v == nil {
+			return defaultValue
+		}
+
+		switch s := v.(type) {
+		case string:
+			return toLogEntry(s, defaultValue, quoted)
+
+		case fmt.Stringer:
+			return toLogEntry(s.String(), defaultValue, quoted)
+
+		default:
+			return v
+		}
+	}
+	return defaultValue
+
+}
+
+func toLogEntry(s string, defaultValue string, quote bool) string {
+	if len(s) == 0 {
+		return defaultValue
+	}
+
+	if quote {
+		return `"` + s + `"`
+	}
+	return s
+}