Initial commit

README.md

@@ -0,0 +1,11 @@
+# logrus-levelpad-formatter
+
+Logrus (https://github.com/sirupsen/logrus) formatter with messages like
+
+```
+[INFO]: 2006-01-02T15:04:05Z07:00 - Log message
+```
+
+Configure
+
+...

formatter.go

@@ -0,0 +1,65 @@
+package levelpad
+
+import (
+	"strings"
+	"time"
+
+	"github.com/sirupsen/logrus"
+)
+
+const (
+	// Default log format will output [INFO]: 2006-01-02T15:04:05Z07:00 - Log message
+	defaultLogFormat       = "[%lvl%]: %time% - %msg%"
+	defaultTimestampFormat = time.RFC3339
+)
+
+func padRight(str, pad string, length int) string {
+	for {
+		str += pad
+		if len(str) > length {
+			return str[0:length]
+		}
+	}
+}
+
+// Formatter implements logrus.Formatter interface.
+type Formatter struct {
+	// Timestamp format
+	TimestampFormat string
+	// Available standard keys: time, msg, lvl
+	// Also can include custom fields but limited to strings.
+	// All of fields need to be wrapped inside %% i.e %time% %msg%
+	LogFormat string
+	LevelPad int
+}
+
+// Format building log message.
+func (f *Formatter) Format(entry *logrus.Entry) ([]byte, error) {
+	output := f.LogFormat
+	if output == "" {
+		output = defaultLogFormat
+	}
+
+	timestampFormat := f.TimestampFormat
+	if timestampFormat == "" {
+		timestampFormat = defaultTimestampFormat
+	}
+
+	output = strings.Replace(output, "%time%", entry.Time.Format(timestampFormat), 1)
+
+	output = strings.Replace(output, "%msg%", entry.Message, 1)
+
+	level := strings.ToUpper(entry.Level.String())
+	if f.LevelPad != 0 {
+		level = padRight(level, " ", f.LevelPad)
+	}
+	output = strings.Replace(output, "%lvl%", level, 1)
+
+	for k, v := range entry.Data {
+		if s, ok := v.(string); ok {
+			output = strings.Replace(output, "%"+k+"%", s, 1)
+		}
+	}
+
+	return []byte(output), nil
+}