fix json marshal of errkit.ErrX

Author: tarunKoyalwar

errkit/errors.go

@@ -59,6 +59,21 @@ func (e *ErrorX) append(errs ...error) {
 	}
 }
 
+func (e ErrorX) MarshalJSON() ([]byte, error) {
+	tmp := []string{}
+	for _, err := range e.errs {
+		tmp = append(tmp, err.Error())
+	}
+	m := map[string]interface{}{
+		"kind":   e.kind.String(),
+		"errors": tmp,
+	}
+	if len(e.attrs) > 0 {
+		m["attrs"] = slog.GroupValue(maps.Values(e.attrs)...)
+	}
+	return json.Marshal(m)
+}
+
 // Errors returns all errors parsed by the error
 func (e *ErrorX) Errors() []error {
 	return e.errs
@@ -97,18 +112,6 @@ func (e *ErrorX) Is(err error) bool {
 	return false
 }
 
-// MarshalJSON returns the json representation of the error
-func (e *ErrorX) MarshalJSON() ([]byte, error) {
-	m := map[string]interface{}{
-		"kind":   e.kind.String(),
-		"errors": e.errs,
-	}
-	if len(e.attrs) > 0 {
-		m["attrs"] = slog.GroupValue(maps.Values(e.attrs)...)
-	}
-	return json.Marshal(m)
-}
-
 // Error returns the error string
 func (e *ErrorX) Error() string {
 	var sb strings.Builder
@@ -158,7 +161,9 @@ func FromError(err error) *ErrorX {
 
 // New creates a new error with the given message
 func New(format string, args ...interface{}) *ErrorX {
-	return &ErrorX{errs: []error{fmt.Errorf(format, args...)}}
+	e := &ErrorX{}
+	e.append(fmt.Errorf(format, args...))
+	return e
 }
 
 // Msgf adds a message to the error

errkit/errors_test.go

@@ -1,6 +1,7 @@
 package errkit
 
 import (
+	"encoding/json"
 	"testing"
 
 	"github.com/pkg/errors"
@@ -105,3 +106,11 @@ func TestErrKindCheck(t *testing.T) {
 		require.True(t, errx.kind.Is(ErrKindNetworkPermanent), "expected to be able to find the original error")
 	})
 }
+
+func TestMarshalError(t *testing.T) {
+	x := New("port closed or filtered").SetKind(ErrKindNetworkPermanent)
+	wrapped := Wrap(x, "this is a wrapped error")
+	marshalled, err := json.Marshal(wrapped)
+	require.NoError(t, err, "expected to be able to marshal the error")
+	require.Equal(t, `{"errors":["port closed or filtered","this is a wrapped error"],"kind":"network-permanent-error"}`, string(marshalled))
+}