feat(assets-controller): use AccountsAPI v6 balances

README.md

@@ -281,6 +281,7 @@ linkStyle default opacity:0.5
   assets_controller --> phishing_controller;
   assets_controller --> polling_controller;
   assets_controller --> preferences_controller;
+  assets_controller --> remote_feature_flag_controller;
   assets_controller --> transaction_controller;
   assets_controllers --> account_tree_controller;
   assets_controllers --> accounts_controller;

packages/assets-controller/CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Add Robinhood Chain (`4663`/`0x1237`) in `MulticallClient` ([#9443](https://github.com/MetaMask/core/pull/9443))
+- `AccountsApiDataSource` now selects the Accounts API balances endpoint version from the `RemoteFeatureFlagController` (`assetsAccountsApiV6` flag, read per fetch off the shared messenger, default v5) so the v6 endpoint is gated consistently across clients (extension, mobile) without each client wiring a getter. The flag is read as a JSON variation shaped `{ value: boolean }` (same shape as `backendWebSocketConnection`). Adds a required `messenger` option and `RemoteFeatureFlagController:getState` to `AccountsApiDataSourceAllowedActions`. Only `category: 'token'` rows from the v6 response are consumed (DeFi positions are ignored) to preserve parity with v5 ([#9344](https://github.com/MetaMask/core/pull/9344))
 
 ### Changed
 

packages/assets-controller/package.json

@@ -74,6 +74,7 @@
     "@metamask/phishing-controller": "^17.2.0",
     "@metamask/polling-controller": "^16.0.8",
     "@metamask/preferences-controller": "^23.1.0",
+    "@metamask/remote-feature-flag-controller": "^4.2.2",
     "@metamask/snaps-controllers": "^19.0.0",
     "@metamask/snaps-utils": "^12.1.2",
     "@metamask/transaction-controller": "^68.3.0",

packages/assets-controller/src/AssetsController.test.ts

@@ -18,6 +18,7 @@ import type {
   AssetsControllerMessenger,
   AssetsControllerState,
 } from './AssetsController';
+import type { AccountsApiDataSourceConfig } from './data-sources/AccountsApiDataSource';
 import type { PriceDataSourceConfig } from './data-sources/PriceDataSource';
 import { PriceDataSource } from './data-sources/PriceDataSource';
 import { TokenDataSource } from './data-sources/TokenDataSource';
@@ -121,10 +122,16 @@ type WithControllerOptions = {
    * Required for tests that rely on asset tracking running (e.g. trace on unlock).
    */
   clientControllerState?: { isUiOpen: boolean };
+  /**
+   * When set, registers RemoteFeatureFlagController:getState so the controller can
+   * read feature flags (e.g. `assetsAccountsApiV6` gating the balances endpoint).
+   */
+  remoteFeatureFlags?: Record<string, unknown>;
   /** Extra options passed to AssetsController constructor (e.g. trace). */
   controllerOptions?: Partial<{
     trace: TraceCallback;
     priceDataSourceConfig: PriceDataSourceConfig;
+    accountsApiDataSourceConfig: AccountsApiDataSourceConfig;
     isEnabled: () => boolean;
     captureException: (error: Error) => void;
     tempMigrateAssetsInfoMetadataAssets3346: () => Assets3346MigrationState;
@@ -156,6 +163,7 @@ async function withController<ReturnValue>(
       state = {},
       isBasicFunctionality = (): boolean => true,
       clientControllerState,
+      remoteFeatureFlags,
       queryApiClient = createMockQueryApiClient(),
       controllerOptions = {},
     },
@@ -230,6 +238,17 @@ async function withController<ReturnValue>(
     );
   }
 
+  if (remoteFeatureFlags !== undefined) {
+    (
+      messenger as {
+        registerActionHandler: (a: string, h: () => unknown) => void;
+      }
+    ).registerActionHandler('RemoteFeatureFlagController:getState', () => ({
+      remoteFeatureFlags,
+      cacheTimestamp: 0,
+    }));
+  }
+
   const controller = new AssetsController({
     messenger: messenger as unknown as AssetsControllerMessenger,
     state,
@@ -878,6 +897,51 @@ describe('AssetsController', () => {
       });
     });
 
+    // Endpoint selection from the flag is unit-tested in AccountsApiDataSource;
+    // this asserts the controller wires its messenger through so the
+    // `assetsAccountsApiV6` flag drives endpoint selection end-to-end.
+    it('routes to the Accounts API v6 endpoint when the assetsAccountsApiV6 remote flag is enabled', async () => {
+      const fetchV6MultiAccountBalances = jest.fn().mockResolvedValue({
+        accounts: [],
+        unprocessedNetworks: [],
+        unprocessedIncludeAssetIds: [],
+      });
+      const fetchV5MultiAccountBalances = jest.fn().mockResolvedValue({
+        balances: [],
+        unprocessedNetworks: [],
+      });
+
+      const queryApiClient = {
+        ...createMockQueryApiClient(),
+        accounts: {
+          fetchV2SupportedNetworks: jest.fn().mockResolvedValue({
+            fullSupport: [1],
+            partialSupport: [],
+          }),
+          fetchV6MultiAccountBalances,
+          fetchV5MultiAccountBalances,
+        },
+      } as unknown as ApiPlatformClient;
+
+      await withController(
+        {
+          queryApiClient,
+          remoteFeatureFlags: { assetsAccountsApiV6: { value: true } },
+        },
+        async ({ controller }) => {
+          await flushPromises();
+
+          await controller.getAssets([createMockInternalAccount()], {
+            chainIds: ['eip155:1'],
+            forceUpdate: true,
+          });
+
+          expect(fetchV6MultiAccountBalances).toHaveBeenCalled();
+          expect(fetchV5MultiAccountBalances).not.toHaveBeenCalled();
+        },
+      );
+    });
+
     describe('pipeline splitting', () => {
       it('returns from getAssets before background pipelines complete', async () => {
         // Spy on handleAssetsUpdate to count how many times state is written.

packages/assets-controller/src/AssetsController.ts

@@ -48,6 +48,7 @@ import type {
 } from '@metamask/permission-controller';
 import { PhishingControllerBulkScanTokensAction } from '@metamask/phishing-controller';
 import type { PreferencesControllerStateChangeEvent } from '@metamask/preferences-controller';
+import type { RemoteFeatureFlagControllerGetStateAction } from '@metamask/remote-feature-flag-controller';
 import type {
   SnapControllerGetRunnableSnapsAction,
   SnapControllerHandleRequestAction,
@@ -321,7 +322,9 @@ type AllowedActions =
   // BackendWebsocketDataSource
   | BackendWebSocketServiceActions
   // PhishingController
-  | PhishingControllerBulkScanTokensAction;
+  | PhishingControllerBulkScanTokensAction
+  // AccountsApiDataSource (Accounts API v6 balances feature flag)
+  | RemoteFeatureFlagControllerGetStateAction;
 
 type AccountTreeControllerStateChangedEvent = ControllerStateChangedEvent<
   'AccountTreeController',
@@ -914,6 +917,7 @@ export class AssetsController extends BaseController<
         this.#getAssetType(assetId),
     });
     this.#accountsApiDataSource = new AccountsApiDataSource({
+      messenger: this.messenger,
       queryApiClient,
       onActiveChainsUpdated: this.#onActiveChainsUpdated,
       ...accountsApiDataSourceConfig,