Merge pull request #26 from m-mizutani/fix/redact-string-any

fix(redact): RedactString to handle any in map

redactor.go

@@ -23,12 +23,23 @@ func (x Redactors) Redact(src, dst reflect.Value) bool {
 // RedactString is a redactor to redact string value. It receives a function to redact string. The function receives the string value and returns the redacted string value. The returned Redact function always returns true if the source value is string. Otherwise, it returns false.
 func RedactString(redact func(s string) string) Redactor {
 	return func(src, dst reflect.Value) bool {
-		if src.Kind() != reflect.String {
-			return false
+		if src.Kind() == reflect.String {
+			dst.Elem().SetString(redact(src.String()))
+			return true
+		}
+
+		// If the source value is `any`, not nil and string, it should be redacted.
+		if src.Kind() == reflect.Interface && !src.IsNil() {
+			elem := src.Elem()
+			if elem.Kind() == reflect.String {
+				redacted := redact(elem.String())
+				// Destination value is also `any`, so it should use `Set` to set the redacted string value instead of `SetString`.
+				dst.Elem().Set(reflect.ValueOf(redacted))
+				return true
+			}
 		}
 
-		dst.Elem().SetString(redact(src.String()))
-		return true
+		return false
 	}
 }
 

redactor_test.go

@@ -1,6 +1,11 @@
 package masq_test
 
 import (
+	"bytes"
+	"log/slog"
+	"testing"
+
+	"github.com/m-mizutani/gt"
 	"github.com/m-mizutani/masq"
 )
 
@@ -28,3 +33,16 @@ func ExampleMaskWithSymbol() {
 	// Output:
 	// {"level":"INFO","msg":"Got record","record":{"Email":"************ (remained 36 chars)","ID":"m-mizutani","Phone":"*************"},"time":"2022-12-25T09:00:00.123456789"}
 }
+
+func TestMapAny(t *testing.T) {
+	var buf bytes.Buffer
+	logger := slog.New(slog.NewJSONHandler(&buf, &slog.HandlerOptions{
+		ReplaceAttr: masq.New(
+			masq.WithFieldName("Secret", masq.RedactString(func(s string) string {
+				return "REDACTED"
+			})),
+		),
+	}))
+	logger.Info("hello", slog.Any("target", map[string]any{"Secret": "xxx"}))
+	gt.S(t, buf.String()).Contains("REDACTED")
+}