feat: add FillID() method for Consumer Group (#357)

CHANGELOG.md

@@ -61,7 +61,9 @@
 
 > Release date: TBD
 
-- Added support for scoping plugins to consumer-groups.
+- Added method `FillID()` method for Consumer Group.
+  [#357](https://github.com/Kong/go-kong/pull/357)
+- Added support for scoping plugins to Consumer Groups.
   [#352](https://github.com/Kong/go-kong/pull/352)
 
 ## [v0.45.0]

kong/consumer_group.go

@@ -44,12 +44,12 @@ type ConsumerGroupPlugin struct {
 }
 
 // FriendlyName returns the endpoint key name or ID.
-func (s *ConsumerGroup) FriendlyName() string {
-	if s.Name != nil {
-		return *s.Name
+func (cg *ConsumerGroup) FriendlyName() string {
+	if cg.Name != nil {
+		return *cg.Name
 	}
-	if s.ID != nil {
-		return *s.ID
+	if cg.ID != nil {
+		return *cg.ID
 	}
 	return ""
 }

kong/ids.go

@@ -79,6 +79,30 @@ func (c *Consumer) FillID() error {
 	return nil
 }
 
+// FillID fills the ID of an entity. It is a no-op if the entity already has an ID.
+// ID is generated in a deterministic way using UUIDv5. The UUIDv5 namespace is different for each entity type.
+// The name used to generate the ID for ConsumerGroup is ConsumerGroup.Name.
+func (cg *ConsumerGroup) FillID() error {
+	if cg == nil {
+		return fmt.Errorf("consumer group is nil")
+	}
+	if cg.ID != nil {
+		// ID already set, do nothing.
+		return nil
+	}
+	if cg.Name == nil || *cg.Name == "" {
+		return fmt.Errorf("consumer group name is required")
+	}
+
+	gen, err := idGeneratorFor(cg)
+	if err != nil {
+		return fmt.Errorf("could not get id generator: %w", err)
+	}
+
+	cg.ID = gen.buildIDFor(*cg.Name)
+	return nil
+}
+
 var (
 	// _kongEntitiesNamespace is the UUIDv5 namespace used to generate IDs for Kong entities.
 	_kongEntitiesNamespace = uuid.MustParse("fd02801f-0957-4a15-a55a-c8d9606f30b5")
@@ -88,9 +112,10 @@ var (
 	// names for that purpose.
 	// See https://github.com/Kong/kong/blob/master/kong/db/schema/others/declarative_config.lua for reference.
 	_idGenerators = map[reflect.Type]idGenerator{
-		reflect.TypeOf(Service{}):  newIDGeneratorFor("services"),
-		reflect.TypeOf(Route{}):    newIDGeneratorFor("routes"),
-		reflect.TypeOf(Consumer{}): newIDGeneratorFor("consumers"),
+		reflect.TypeOf(Service{}):       newIDGeneratorFor("services"),
+		reflect.TypeOf(Route{}):         newIDGeneratorFor("routes"),
+		reflect.TypeOf(Consumer{}):      newIDGeneratorFor("consumers"),
+		reflect.TypeOf(ConsumerGroup{}): newIDGeneratorFor("consumergroups"),
 	}
 )
 

kong/ids_test.go

@@ -104,6 +104,35 @@ func TestFillEntityID(t *testing.T) {
 				require.Equal(t, expectedID, *consumer.ID, "ID should be deterministic")
 			},
 		},
+		// Consumer Group
+		{
+			name:      "consumer group nil pointer",
+			entity:    (*kong.ConsumerGroup)(nil),
+			expectErr: true,
+		},
+		{
+			name:      "consumer group with nil name",
+			entity:    &kong.ConsumerGroup{},
+			expectErr: true,
+		},
+		{
+			name:      "consumer group with empty name",
+			entity:    &kong.ConsumerGroup{Name: kong.String("")},
+			expectErr: true,
+		},
+		{
+			name: "consumer group with name",
+			entity: &kong.ConsumerGroup{
+				Name: kong.String("some.consumer.group"),
+			},
+			assertEntity: func(t *testing.T, e kong.IDFillable) {
+				cg := e.(*kong.ConsumerGroup)
+				require.NotNil(t, cg.ID)
+
+				const expectedID = "e5643801-37c6-5d04-9d3f-c1c84c747e90"
+				require.Equal(t, expectedID, *cg.ID, "ID should be deterministic")
+			},
+		},
 	}
 
 	for _, tc := range testCases {