add ParseLevel func to return level const

log/log.go

@@ -9,6 +9,7 @@ import (
 	"path"
 	"runtime"
 	"strconv"
+	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -248,6 +249,24 @@ func Level() Lvl {
 	return global.Level()
 }
 
+func ParseLevel(lvl string) (Lvl, error) {
+	switch strings.ToUpper(lvl) {
+	case "DEBUG":
+		return DEBUG, nil
+	case "INFO":
+		return INFO, nil
+	case "WARN":
+		return WARN, nil
+	case "ERROR":
+		return ERROR, nil
+	case "OFF":
+		return OFF, nil
+	}
+
+	var l Lvl
+	return l, fmt.Errorf("not a valid log level: '%s'", lvl)
+}
+
 func SetLevel(level Lvl) {
 	global.SetLevel(level)
 }

log/log_test.go

@@ -2,6 +2,7 @@ package log
 
 import (
 	"bytes"
+	"errors"
 	"os"
 	"os/exec"
 	"sync"
@@ -75,6 +76,31 @@ func TestFatal(t *testing.T) {
 	loggerFatalTest(t, "fatalf", "fatal-f")
 }
 
+func TestParseLevel(t *testing.T) {
+	testCases := map[string]struct {
+		input       string
+		expectedLvl Lvl
+		expectedErr error
+	}{
+		"DEBUG":     {"DEBUG", DEBUG, nil},
+		"INFO":      {"INFO", INFO, nil},
+		"WARN":      {"WARN", WARN, nil},
+		"ERROR":     {"ERROR", ERROR, nil},
+		"OFF":       {"OFF", OFF, nil},
+		"lowercase": {"debug", DEBUG, nil},
+		"mixedcase": {"WaRn", WARN, nil},
+		"unknown":   {"UNKNOWN", 0, errors.New("not a valid log level: 'UNKNOWN'")},
+	}
+
+	for name, testCase := range testCases {
+		t.Run(name, func(t *testing.T) {
+			lvl, err := ParseLevel(testCase.input)
+			assert.Equal(t, testCase.expectedLvl, lvl)
+			assert.Equal(t, testCase.expectedErr, err)
+		})
+	}
+}
+
 func loggerFatalTest(t *testing.T, env string, contains string) {
 	buf := new(bytes.Buffer)
 	cmd := exec.Command(os.Args[0], "-test.run=TestFatal")