fix: update consumers when custom_id is also set

Right now decK only uses ID and Username for Consumers lookup,
which is problematic because CustomID is also unique and
modifying a Username causes a Consumer re-creation, which
triggers a collision for the CustomID field.

This PR makes sure that CustomID is included in the lookup
loop, so that such Consumers changes can be made in-place.

CHANGELOG.md

@@ -1,5 +1,6 @@
 # Table of Contents
 
+- [Unreleased](#Unreleased)
 - [v1.12.2](#v1122)
 - [v1.12.1](#v1121)
 - [v1.12.0](#v1120)
@@ -39,6 +40,16 @@
 - [v0.2.0](#v020)
 - [v0.1.0](#v010)
 
+## [Unreleased]
+
+> Release date: TBD
+
+### Fixes
+
+- Make sure decK can update in place consumers' username when
+  `custom_id` is also set.
+  [#707](https://github.com/Kong/deck/pull/707)
+
 ## [v1.12.2]
 
 > Release date: 2022/06/06
@@ -947,6 +958,7 @@ No breaking changes have been introduced in this release.
 
 Debut release of decK
 
+[Unreleased]: https://github.com/kong/deck/compare/v1.12.2...Unreleased
 [v1.12.2]: https://github.com/kong/deck/compare/v1.12.1...v1.12.2
 [v1.12.1]: https://github.com/kong/deck/compare/v1.12.0...v1.12.1
 [v1.12.0]: https://github.com/kong/deck/compare/v1.11.0...v1.12.0

file/builder.go

@@ -181,7 +181,15 @@ func (b *stateBuilder) consumers() {
 		if utils.Empty(c.ID) {
 			consumer, err := b.currentState.Consumers.Get(*c.Username)
 			if err == state.ErrNotFound {
-				c.ID = uuid()
+				if c.CustomID != nil {
+					consumer, err = b.currentState.Consumers.Get(*c.CustomID)
+					if err == nil {
+						c.ID = kong.String(*consumer.ID)
+					}
+				}
+				if c.ID == nil {
+					c.ID = uuid()
+				}
 			} else if err != nil {
 				b.err = err
 				return

state/consumer.go

@@ -25,6 +25,12 @@ var consumerTableSchema = &memdb.TableSchema{
 			Indexer:      &memdb.StringFieldIndex{Field: "Username"},
 			AllowMissing: true,
 		},
+		"CustomID": {
+			Name:         "CustomID",
+			Unique:       true,
+			Indexer:      &memdb.StringFieldIndex{Field: "CustomID"},
+			AllowMissing: true,
+		},
 		all: allIndex,
 	},
 }
@@ -47,6 +53,9 @@ func (k *ConsumersCollection) Add(consumer Consumer) error {
 	if !utils.Empty(consumer.Username) {
 		searchBy = append(searchBy, *consumer.Username)
 	}
+	if !utils.Empty(consumer.CustomID) {
+		searchBy = append(searchBy, *consumer.CustomID)
+	}
 	_, err := getConsumer(txn, searchBy...)
 	if err == nil {
 		return fmt.Errorf("inserting consumer %v: %w", consumer.Console(), ErrAlreadyExists)
@@ -65,7 +74,7 @@ func (k *ConsumersCollection) Add(consumer Consumer) error {
 func getConsumer(txn *memdb.Txn, IDs ...string) (*Consumer, error) {
 	for _, id := range IDs {
 		res, err := multiIndexLookupUsingTxn(txn, consumerTableName,
-			[]string{"Username", "id"}, id)
+			[]string{"Username", "id", "CustomID"}, id)
 		if err == ErrNotFound {
 			continue
 		}

tests/integration/sync_test.go

@@ -1277,3 +1277,89 @@ func Test_Sync_PluginsOnEntities(t *testing.T) {
 		})
 	}
 }
+
+func Test_Sync_UpdateUsernameInConsumerWithCustomID(t *testing.T) {
+	// setup stage
+	client, err := getTestClient()
+	if err != nil {
+		t.Errorf(err.Error())
+	}
+
+	tests := []struct {
+		name            string
+		kongFile        string
+		kongFileInitial string
+		expectedState   utils.KongRawState
+	}{
+		{
+			name:            "update username on a consumer with custom_id",
+			kongFile:        "testdata/sync/011-update-username-consumer-with-custom-id/kong.yaml",
+			kongFileInitial: "testdata/sync/011-update-username-consumer-with-custom-id/kong-initial.yaml",
+			expectedState: utils.KongRawState{
+				Consumers: []*kong.Consumer{
+					{
+						Username: kong.String("test_new"),
+						CustomID: kong.String("custom_test"),
+					},
+				},
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			kong.RunWhenKong(t, ">=2.8.0")
+			teardown := setup(t)
+			defer teardown(t)
+
+			// set up initial state
+			sync(tc.kongFileInitial)
+			// update with desired final state
+			sync(tc.kongFile)
+			testKongState(t, client, tc.expectedState, nil)
+		})
+	}
+}
+
+func Test_Sync_UpdateConsumerWithCustomID(t *testing.T) {
+	// setup stage
+	client, err := getTestClient()
+	if err != nil {
+		t.Errorf(err.Error())
+	}
+
+	tests := []struct {
+		name            string
+		kongFile        string
+		kongFileInitial string
+		expectedState   utils.KongRawState
+	}{
+		{
+			name:            "update username on a consumer with custom_id",
+			kongFile:        "testdata/sync/012-update-consumer-with-custom-id/kong.yaml",
+			kongFileInitial: "testdata/sync/012-update-consumer-with-custom-id/kong-initial.yaml",
+			expectedState: utils.KongRawState{
+				Consumers: []*kong.Consumer{
+					{
+						Username: kong.String("test"),
+						CustomID: kong.String("new_custom_test"),
+					},
+				},
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			kong.RunWhenKong(t, ">=2.8.0")
+			teardown := setup(t)
+			defer teardown(t)
+
+			// set up initial state
+			sync(tc.kongFileInitial)
+			// update with desired final state
+			sync(tc.kongFile)
+			testKongState(t, client, tc.expectedState, nil)
+		})
+	}
+}

tests/integration/test_utils.go

@@ -88,7 +88,7 @@ func testKongState(t *testing.T, client *kong.Client,
 		cmpopts.IgnoreFields(kong.CACertificate{}, "ID", "CreatedAt"),
 		cmpopts.IgnoreFields(kong.RBACEndpointPermission{}, "Role", "CreatedAt"),
 		cmpopts.IgnoreFields(kong.RBACRole{}, "ID", "CreatedAt"),
-		cmpopts.IgnoreFields(kong.Consumer{}, "CreatedAt"),
+		cmpopts.IgnoreFields(kong.Consumer{}, "ID", "CreatedAt"),
 		cmpopts.SortSlices(sortSlices),
 		cmpopts.SortSlices(func(a, b *string) bool { return *a < *b }),
 		cmpopts.EquateEmpty(),

tests/integration/testdata/sync/011-update-username-consumer-with-custom-id/kong-initial.yaml

@@ -0,0 +1,4 @@
+_format_version: "1.1"
+consumers:
+- custom_id: custom_test
+  username: test

tests/integration/testdata/sync/011-update-username-consumer-with-custom-id/kong.yaml

@@ -0,0 +1,4 @@
+_format_version: "1.1"
+consumers:
+- custom_id: custom_test
+  username: test_new

tests/integration/testdata/sync/012-update-consumer-with-custom-id/kong-initial.yaml

@@ -0,0 +1,4 @@
+_format_version: "1.1"
+consumers:
+- custom_id: custom_test
+  username: test

tests/integration/testdata/sync/012-update-consumer-with-custom-id/kong.yaml

@@ -0,0 +1,4 @@
+_format_version: "1.1"
+consumers:
+- custom_id: new_custom_test
+  username: test