Add a function to retrieve a log level by name (useful for config)

logging.go

@@ -1,6 +1,7 @@
 package logging
 
 import (
+	"errors"
 	"fmt"
 	"strings"
 )
@@ -25,6 +26,15 @@ func (l Level) Name() string {
 	return levelNames[l]
 }
 
+func LevelByName(l string) (Level, error) {
+	for pos, name := range levelNames {
+		if name == l {
+			return Level(pos), nil
+		}
+	}
+	return DEBUG, errors.New(fmt.Sprintf("Invalid log level %s", l))
+}
+
 type Formatter func(*Record) string
 
 func GetLogger() (l *Logger) {

logging_test.go

@@ -0,0 +1,15 @@
+package logging
+
+import "testing"
+
+func Test_LevelByName(t *testing.T) {
+	for _, levelName := range levelNames {
+		l, e := LevelByName(levelName)
+		if e != nil {
+			t.Errorf("level %s not recognized", levelName)
+		}
+		if l.Name() != levelName {
+			t.Errorf("expected '%s', got '%s'", levelName, l.Name())
+		}
+	}
+}