Merge branch 'main' into update-gateway-images-in-ci

CHANGELOG.md

@@ -59,7 +59,8 @@
 
 > Release date: TBD
 
-Nothing yet.
+- Fix: handle empty array as nil when filling record defaults
+  [#345](https://github.com/Kong/go-kong/pull/345)
 
 ## [v0.43.0]
 

kong/utils.go

@@ -253,11 +253,19 @@ func fillConfigRecord(schema gjson.Result, config Configuration) Configuration {
 		frequired := value.Get(fname + ".required")
 		// Recursively fill defaults only if the field is either required or a subconfig is provided
 		if ftype.String() == "record" && (config[fname] != nil || (frequired.Exists() && frequired.Bool())) {
+			var fieldConfig Configuration
 			subConfig := config[fname]
-			if subConfig == nil {
-				subConfig = make(map[string]interface{})
+			switch subConfig.(type) {
+			case nil, []interface{}:
+				// We can encounter an empty array here due to an incorrect yaml
+				// setting or an empty subconfig (like acme.storage_config.kong).
+				// This should be treated as nil case.
+				// TODO: https://konghq.atlassian.net/browse/KOKO-1125
+				fieldConfig = make(map[string]interface{})
+			default:
+				fieldConfig = subConfig.(map[string]interface{})
 			}
-			newSubConfig := fillConfigRecord(value.Get(fname), subConfig.(map[string]interface{}))
+			newSubConfig := fillConfigRecord(value.Get(fname), fieldConfig)
 			res[fname] = map[string]interface{}(newSubConfig)
 			return true
 		}

kong/utils_test.go

@@ -1656,51 +1656,92 @@ func TestFillConsumerGroupPluginDefaults(T *testing.T) {
 	}
 }
 
-func Test_fillConfigRecord(t *testing.T) {
-	tests := []struct {
-		name     string
-		schema   gjson.Result
-		config   Configuration
-		expected Configuration
-	}{
-		{
-			name: "fills defaults for all missing fields",
-			schema: gjson.Parse(`{
-				"fields": {
-					"config":
-						{
+const fillConfigRecordTestSchema = `{
+	"fields": {
+		"config": {
+			"type": "record",
+			"fields": [
+				{
+					"enabled": {
+						"type": "boolean",
+						"default": true,
+						"required": true
+					}
+				},
+				{
+					"mappings": {
+						"required": false,
+						"type": "array",
+						"elements": {
 							"type": "record",
-							"fields":[
+							"fields": [
 								{
-									"enabled":{
-										"type":"boolean",
-										"default":true,
-										"required":true
+									"name": {
+										"type": "string",
+										"required": false
 									}
 								},
 								{
-									"mappings":{
-										"required":false,
-										"type":"array",
-										"elements":{
-											"type":"record",
-											"fields":[
-												{"name":{"type":"string","required":false}},
-												{"nationality":{"type":"string","required":false}}
-											]
-										}
+									"nationality": {
+										"type": "string",
+										"required": false
 									}
 								}
 							]
 						}
 					}
-				}`),
+				},
+				{
+					"empty_record": {
+						"type": "record",
+						"required": true,
+						"fields": []
+					}
+				}
+			]
+		}
+	}
+}
+`
+
+func Test_fillConfigRecord(t *testing.T) {
+	tests := []struct {
+		name     string
+		schema   gjson.Result
+		config   Configuration
+		expected Configuration
+	}{
+		{
+			name:   "fills defaults for all missing fields",
+			schema: gjson.Parse(fillConfigRecordTestSchema),
+			config: Configuration{
+				"mappings": []any{
+					map[string]any{
+						"nationality": "Ethiopian",
+					},
+				},
+			},
+			expected: Configuration{
+				"enabled": true,
+				"mappings": []any{
+					Configuration{
+						"name":        nil,
+						"nationality": "Ethiopian",
+					},
+				},
+				"empty_record": map[string]any{},
+			},
+		},
+		{
+			name:   "handle empty array as nil for a record field",
+			schema: gjson.Parse(fillConfigRecordTestSchema),
 			config: Configuration{
-				"mappings": []interface{}{
-					map[string]interface{}{
+				"mappings": []any{
+					map[string]any{
 						"nationality": "Ethiopian",
 					},
 				},
+				"empty_record": map[string]any{},
 			},
 			expected: Configuration{
 				"enabled": true,
@@ -1710,6 +1751,7 @@ func Test_fillConfigRecord(t *testing.T) {
 						"nationality": "Ethiopian",
 					},
 				},
+				"empty_record": map[string]any{},
 			},
 		},
 	}