fix: correctly unmarshal key value list

jsonpointer/resolve.go

@@ -25,6 +25,14 @@ func Resolve(base any, pointer Pointer) (any, error) {
 }
 
 func findByLabel(base reflect.Value, jsonLabel string) (reflect.Value, bool) {
+	if resolver, ok := base.Interface().(LabelResolver); ok {
+		value, ok := resolver.ResolveJsonLabel(jsonLabel)
+		if ok {
+			return reflect.ValueOf(value).Elem(), true
+		}
+		return reflect.Value{}, false
+	}
+
 	for base.Kind() == reflect.Ptr || base.Kind() == reflect.Interface {
 		if base.IsNil() {
 			return reflect.Value{}, false
@@ -75,3 +83,10 @@ func findStructFieldByLabel(base reflect.Value, label string) (reflect.Value, bo
 	}
 	return reflect.Value{}, false
 }
+
+type LabelResolver interface {
+	// ResolveJsonLabel resolves the given JSON label to a value.
+	// If the label is not found, (nil, false) is returned.
+	// The returned value must be a pointer to the field.
+	ResolveJsonLabel(label string) (any, bool)
+}

thorlog/v3/kvlist.go

@@ -14,22 +14,20 @@ type KeyValue struct {
 	Value string
 }
 
-type KeyValueList struct {
-	KvList []KeyValue
-}
+type KeyValueList []KeyValue
 
 func (d KeyValueList) MarshalJSON() ([]byte, error) {
 	var builder strings.Builder
 	builder.WriteString("{")
-	for i, kv := range d.KvList {
+	for i, kv := range d {
 		if err := json.NewEncoder(&builder).Encode(kv.Key); err != nil {
 			return nil, err
 		}
 		builder.WriteString(": ")
 		if err := json.NewEncoder(&builder).Encode(kv.Value); err != nil {
 			return nil, err
 		}
-		if i < len(d.KvList)-1 {
+		if i < len(d)-1 {
 			builder.WriteString(", ")
 		}
 	}
@@ -48,16 +46,22 @@ func (d *KeyValueList) UnmarshalJSON(data []byte) error {
 	}
 	var kvList []KeyValue
 	for decoder.More() {
-		var key string
-		err = decoder.Decode(&key)
+		keyToken, err := decoder.Token()
 		if err != nil {
 			return err
 		}
-		var value string
-		err = decoder.Decode(&value)
+		key, isString := keyToken.(string)
+		if !isString {
+			return errors.New("expected string key")
+		}
+		valueToken, err := decoder.Token()
 		if err != nil {
 			return err
 		}
+		value, isString := valueToken.(string)
+		if !isString {
+			return errors.New("expected string value")
+		}
 		kvList = append(kvList, KeyValue{Key: key, Value: value})
 	}
 	token, err = decoder.Token()
@@ -67,18 +71,27 @@ func (d *KeyValueList) UnmarshalJSON(data []byte) error {
 	if delim, isDelim := token.(json.Delim); !isDelim || delim != '}' {
 		return errors.New("expected '}'")
 	}
-	d.KvList = kvList
+	*d = kvList
 	return nil
 }
 
+func (d KeyValueList) ResolveJsonLabel(label string) (any, bool) {
+	for i := range d {
+		if d[i].Key == label {
+			return &d[i].Value, true
+		}
+	}
+	return nil, false
+}
+
 func (d KeyValueList) RelativeJsonPointer(pointee any) jsonpointer.Pointer {
 	stringPointer, isStringPointer := pointee.(*string)
 	if !isStringPointer {
 		return nil
 	}
-	for i := range d.KvList {
-		if &d.KvList[i].Value == stringPointer {
-			return jsonpointer.New(d.KvList[i].Key)
+	for i := range d {
+		if &d[i].Value == stringPointer {
+			return jsonpointer.New(d[i].Key)
 		}
 	}
 	return nil
@@ -89,30 +102,30 @@ func (d KeyValueList) RelativeTextPointer(pointee any) (string, bool) {
 	if !isStringPointer {
 		return "", false
 	}
-	for i := range d.KvList {
-		if &d.KvList[i].Value == stringPointer {
-			return d.KvList[i].Key, true
+	for i := range d {
+		if &d[i].Value == stringPointer {
+			return d[i].Key, true
 		}
 	}
 	return "", false
 }
 
 func (d KeyValueList) Find(key string) *string {
-	for i := range d.KvList {
-		if d.KvList[i].Key == key {
-			return &d.KvList[i].Value
+	for i := range d {
+		if d[i].Key == key {
+			return &d[i].Value
 		}
 	}
 	return nil
 }
 
 func (d KeyValueList) String() string {
 	var dataBuilder strings.Builder
-	for i, kv := range d.KvList {
+	for i, kv := range d {
 		dataBuilder.WriteString(kv.Key)
 		dataBuilder.WriteString(": ")
 		dataBuilder.WriteString(kv.Value)
-		if i < len(d.KvList)-1 {
+		if i < len(d)-1 {
 			dataBuilder.WriteString("  ")
 		}
 	}

thorlog/v3/kvlist_test.go

@@ -0,0 +1,47 @@
+package thorlog
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/NextronSystems/jsonlog"
+	"github.com/NextronSystems/jsonlog/jsonpointer"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestKeyValueList_MarshalJSON(t *testing.T) {
+	var kvList = KeyValueList{
+		{Key: "key1", Value: "value1"},
+		{Key: "key2", Value: "value2"},
+	}
+	data, err := json.Marshal(kvList)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if string(data) != `{"key1":"value1","key2":"value2"}` {
+		t.Errorf("unexpected JSON: %s", data)
+	}
+	var unmarshaled KeyValueList
+	err = json.Unmarshal(data, &unmarshaled)
+	if err != nil {
+		t.Fatalf("unexpected error during unmarshal: %v", err)
+	}
+	if unmarshaled[0].Key != "key1" || unmarshaled[0].Value != "value1" || unmarshaled[1].Key != "key2" || unmarshaled[1].Value != "value2" {
+		t.Errorf("unexpected unmarshaled data: %+v", unmarshaled)
+	}
+}
+
+func TestKeyValueList_JsonPointers(t *testing.T) {
+	var kvList = KeyValueList{
+		{Key: "key1", Value: "value1"},
+		{Key: "key2", Value: "value2"},
+	}
+	reference := jsonlog.Reference{Base: &kvList, PointedField: &kvList[1].Value}
+	pointer := reference.ToJsonPointer()
+	assert.Equal(t, "/key2", pointer.String())
+
+	reverse, err := jsonpointer.Resolve(&kvList, pointer)
+	require.NoError(t, err)
+	assert.Equal(t, &kvList[1].Value, reverse)
+}