MetaMask · Kriys94 · Mar 25, 2026 · cursor · Mar 27, 2026
@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- `TokenDataSource` splits v3 asset metadata fetches into batches of at most 120 asset IDs per request, matching the Tokens API limit, and runs chunk requests in parallel with bounded concurrency via `p-limit` ([#8294](https://github.com/MetaMask/core/pull/8294))
+- `PriceDataSource` splits v3 spot-price fetches into batches of at most 120 asset IDs per request, matching the same scale as token metadata requests, with bounded concurrency via `p-limit` ([#8294](https://github.com/MetaMask/core/pull/8294))
+
 ## [3.2.0]
 
 ### Added

@@ -710,7 +710,14 @@ export class AssetsController extends BaseController<
       chains: ChainId[],
       previousChains: ChainId[],
     ): void => {
-      this.#handleActiveChainsUpdate(dataSourceName, chains, previousChains);
+      try {
+        this.#handleActiveChainsUpdate(dataSourceName, chains, previousChains);
+      } catch (error) {
+        log('Failed to handle active chains update', {
+          dataSourceName,
+          error,
+        });
+      }
     };
 
     this.#backendWebsocketDataSource = new BackendWebsocketDataSource({

@@ -8,12 +8,12 @@ import {
   MockAnyNamespace,
 } from '@metamask/messenger';
 import { NetworkStatus } from '@metamask/network-controller';
-
 import {
   NetworkState,
   RpcEndpoint,
   RpcEndpointType,
-} from '../../../network-controller/src/NetworkController';
+} from '@metamask/network-controller/src/NetworkController';
+
 import {
   AssetsControllerMessenger,
   getDefaultAssetsControllerState,

@@ -410,6 +410,75 @@ describe('PriceDataSource', () => {
     controller.destroy();
   });
 
+  it('fetch batches spot price requests in chunks of 120 asset IDs', async () => {
+    const assetIds = Array.from({ length: 121 }, (_, i) => {
+      const hexString = i.toString(16).padStart(40, '0');
+      return `eip155:1/erc20:0x${hexString}` as Caip19AssetId;
+    });
+    const balanceState: Record<string, Record<string, unknown>> = {
+      'mock-account-id': Object.fromEntries(
+        assetIds.map((id) => [id, { amount: '1' }]),
+      ),
+    };
+    const priceResponse = Object.fromEntries(
+      assetIds.map((id) => [id, createMockPriceData(1)]),
+    );
+
+    const { controller, apiClient, getAssetsState } = setupController({
+      balanceState,
+      priceResponse,
+    });
+
+    await controller.fetch(createDataRequest({ chainIds: [] }), getAssetsState);
+
+    expect(apiClient.prices.fetchV3SpotPrices).toHaveBeenCalledTimes(2);
+    const chunkSizes = apiClient.prices.fetchV3SpotPrices.mock.calls
+      .map((call) => (call[0] as string[]).length)
+      .sort((a, b) => b - a);
+    expect(chunkSizes).toStrictEqual([120, 1]);
+
+    controller.destroy();
+  });
+
+  it('fetch batches spot price requests per chunk for non-USD currency', async () => {
+    const assetIds = Array.from({ length: 121 }, (_, i) => {
+      const hexString = i.toString(16).padStart(40, '0');
+      return `eip155:1/erc20:0x${hexString}` as Caip19AssetId;
+    });
+    const balanceState: Record<string, Record<string, unknown>> = {
+      'mock-account-id': Object.fromEntries(
+        assetIds.map((id) => [id, { amount: '1' }]),
+      ),
+    };
+    const priceResponse = Object.fromEntries(
+      assetIds.map((id) => [id, createMockPriceData(1)]),
+    );
+
+    const { controller, apiClient, getAssetsState } = setupController({
+      getSelectedCurrency: () => 'eur',
+      balanceState,
+      priceResponse,
+    });
+
+    await controller.fetch(createDataRequest({ chainIds: [] }), getAssetsState);
+
+    expect(apiClient.prices.fetchV3SpotPrices).toHaveBeenCalledTimes(4);
+    const eurChunks = apiClient.prices.fetchV3SpotPrices.mock.calls.filter(
+      (call) => (call[1] as { currency?: string }).currency === 'eur',
+    );
+    const usdChunks = apiClient.prices.fetchV3SpotPrices.mock.calls.filter(
+      (call) => (call[1] as { currency?: string }).currency === 'usd',
+    );
+    expect(eurChunks).toHaveLength(2);
+    expect(usdChunks).toHaveLength(2);
+    const eurSizes = eurChunks
+      .map((call) => (call[0] as string[]).length)
+      .sort((a, b) => b - a);
+    expect(eurSizes).toStrictEqual([120, 1]);
+
+    controller.destroy();
+  });
+
   it('fetch handles getState error gracefully', async () => {
     const { controller } = setupController();
 

@@ -4,6 +4,7 @@ import type {
 } from '@metamask/core-backend';
 import { ApiPlatformClient } from '@metamask/core-backend';
 import { parseCaipAssetType } from '@metamask/utils';
+import pLimit from 'p-limit';
 
 import type { SubscriptionRequest } from './AbstractDataSource';
 import { projectLogger, createModuleLogger } from '../logger';
@@ -24,6 +25,12 @@ import type {
 const CONTROLLER_NAME = 'PriceDataSource';
 const DEFAULT_POLL_INTERVAL = 60_000; // 1 minute for price updates
 
+/** Price API v3 spot-prices accepts at most this many `assetIds` per request (same cap as tokens `/v3/assets`). */
+const V3_SPOT_PRICES_MAX_IDS_PER_REQUEST = 120;
+
+/** Max concurrent spot-price chunk requests (aligned with TokenDataSource metadata fetches). */
+const V3_SPOT_PRICES_FETCH_CONCURRENCY = 3;
+
 const log = createModuleLogger(projectLogger, CONTROLLER_NAME);
 
 // ============================================================================
@@ -219,30 +226,50 @@ export class PriceDataSource {
   async #fetchSpotPrices(
     assetIds: string[],
   ): Promise<Record<Caip19AssetId, FungibleAssetPrice>> {
+    if (assetIds.length === 0) {
+      return {};
+    }
+
     const selectedCurrency = this.#getSelectedCurrency();
+    const chunks: string[][] = [];
+    for (
+      let i = 0;
+      i < assetIds.length;
+      i += V3_SPOT_PRICES_MAX_IDS_PER_REQUEST
+    ) {
+      chunks.push(assetIds.slice(i, i + V3_SPOT_PRICES_MAX_IDS_PER_REQUEST));
+    }
+
+    const limit = pLimit(V3_SPOT_PRICES_FETCH_CONCURRENCY);
+    const queryOpts = { includeMarketData: true as const };
+
+    const selectedChunkResults = await Promise.all(
+      chunks.map((chunk) =>
+        limit(() =>
+          this.#apiClient.prices.fetchV3SpotPrices(chunk, {
+            currency: selectedCurrency,
+            ...queryOpts,
+          }),
+        ),
+      ),
+    );
+    const selectedCurrencyPrices = Object.assign({}, ...selectedChunkResults);
 
-    let selectedCurrencyPrices: V3SpotPricesResponse;
     let usdPrices: V3SpotPricesResponse;
     if (selectedCurrency === 'usd') {
-      selectedCurrencyPrices = await this.#apiClient.prices.fetchV3SpotPrices(
-        assetIds,
-        {
-          currency: selectedCurrency,
-          includeMarketData: true,
-        },
-      );
       usdPrices = selectedCurrencyPrices;
     } else {
-      [selectedCurrencyPrices, usdPrices] = await Promise.all([
-        this.#apiClient.prices.fetchV3SpotPrices(assetIds, {
-          currency: selectedCurrency,
-          includeMarketData: true,
-        }),
-        this.#apiClient.prices.fetchV3SpotPrices(assetIds, {
-          currency: 'usd',
-          includeMarketData: true,
-        }),
-      ]);
+      const usdChunkResults = await Promise.all(
+        chunks.map((chunk) =>
+          limit(() =>
+            this.#apiClient.prices.fetchV3SpotPrices(chunk, {
+              currency: 'usd',
+              ...queryOpts,
+            }),
+          ),
+        ),
+      );
+      usdPrices = Object.assign({}, ...usdChunkResults);
     }
 
     const prices: Record<Caip19AssetId, FungibleAssetPrice> = {};

@@ -281,9 +281,14 @@ export class RpcDataSource extends AbstractDataSource<
       balanceFetcherMessenger,
       { pollingInterval: balanceInterval },
     );
-    this.#balanceFetcher.setOnBalanceUpdate(
-      this.#handleBalanceUpdate.bind(this),
-    );
+    // Polling controller awaits this callback; rejections must not become unhandled.
+    this.#balanceFetcher.setOnBalanceUpdate(async (result) => {
+      try {
+        await this.#handleBalanceUpdate(result);
+      } catch (error) {
+        log('Balance update handler failed', { error });
+      }
+    });
 
     // Initialize TokenDetector with polling interval
     this.#tokenDetector = new TokenDetector(
@@ -295,9 +300,14 @@ export class RpcDataSource extends AbstractDataSource<
         useExternalService: this.#useExternalService,
       },
     );
-    this.#tokenDetector.setOnDetectionUpdate(
-      this.#handleDetectionUpdate.bind(this),
-    );
+    // Sync throw in the detector would reject the poll tick if uncaught.
+    this.#tokenDetector.setOnDetectionUpdate((result) => {
+      try {
+        this.#handleDetectionUpdate(result);
+      } catch (error) {
+        log('Detection update handler failed', { error });
+      }
+    });
 
     this.#subscribeToNetworkController();
     this.#subscribeToTransactionEvents();

@@ -268,10 +268,10 @@ export class SnapDataSource extends AbstractDataSource<
     // Transform the snap keyring payload to DataResponse format
     let assetsBalance: NonNullable<DataResponse['assetsBalance']> | undefined;
 
-    for (const [accountId, assets] of Object.entries(payload.balances)) {
+    for (const [accountId, assets] of Object.entries(payload?.balances ?? {})) {
       let accountAssets: Record<Caip19AssetId, AssetBalance> | undefined;
 
-      for (const [assetId, balance] of Object.entries(assets)) {
+      for (const [assetId, balance] of Object.entries(assets ?? {})) {
         let chainId: ChainId;
         try {
           chainId = extractChainFromAssetId(assetId);

@@ -193,9 +193,14 @@ export class StakedBalanceDataSource extends AbstractDataSource<
     });
 
     // Wire the callback so polling results flow back to subscriptions
-    this.#stakedBalanceFetcher.setOnStakedBalanceUpdate(
-      this.#handleStakedBalanceUpdate.bind(this),
-    );
+    // Polling controller invokes this synchronously; keep failures inside the poll tick.
+    this.#stakedBalanceFetcher.setOnStakedBalanceUpdate((result) => {
+      try {
+        this.#handleStakedBalanceUpdate(result);
+      } catch (error) {
+        log('Staked balance update handler failed', { error });
+      }
+    });
 
     this.#messenger.subscribe(
       'TransactionController:transactionConfirmed',

@@ -429,6 +429,39 @@ describe('TokenDataSource', () => {
     expect(next).toHaveBeenCalledWith(context);
   });
 
+  it('middleware chunks fetchV3Assets when more than 120 asset IDs are requested', async () => {
+    const assetIds = Array.from({ length: 121 }, (_, i) => {
+      const hexString = (i + 1).toString(16).padStart(40, '0');
+      return `eip155:1/erc20:0x${hexString}` as Caip19AssetId;
+    });
+
+    const { controller, apiClient } = setupController({
+      supportedNetworks: ['eip155:1'],
+    });
+
+    apiClient.tokens.fetchV3Assets.mockImplementation((ids: string[]) =>
+      Promise.resolve(ids.map((id) => createMockAssetResponse(id))),
+    );
+
+    const next = jest.fn().mockResolvedValue(undefined);
+    const context = createMiddlewareContext({
+      response: {
+        detectedAssets: {
+          'mock-account-id': assetIds,
+        },
+      },
+    });
+
+    await controller.assetsMiddleware(context, next);
+
+    expect(apiClient.tokens.fetchV3Assets).toHaveBeenCalledTimes(2);
+    expect(apiClient.tokens.fetchV3Assets.mock.calls[0][0]).toHaveLength(120);
+    expect(apiClient.tokens.fetchV3Assets.mock.calls[1][0]).toHaveLength(1);
+    expect(context.response.assetsInfo?.[assetIds[0]]?.symbol).toBe('TEST');
+    expect(context.response.assetsInfo?.[assetIds[120]]?.symbol).toBe('TEST');
+    expect(next).toHaveBeenCalledWith(context);
+  });
+
   it('middleware transforms native asset type correctly', async () => {
     const { controller } = setupController({
       supportedNetworks: ['eip155:1'],

@@ -2,6 +2,7 @@ import type { V3AssetResponse } from '@metamask/core-backend';
 import { ApiPlatformClient } from '@metamask/core-backend';
 import { parseCaipAssetType } from '@metamask/utils';
 import type { CaipAssetType } from '@metamask/utils';
+import pLimit from 'p-limit';
 
 import { isStakingContractAssetId } from './evm-rpc-services';
 import { projectLogger, createModuleLogger } from '../logger';
@@ -19,6 +20,12 @@ import type {
 
 const CONTROLLER_NAME = 'TokenDataSource';
 
+/** Tokens API `/v3/assets` accepts at most this many `assetIds` per request. */
+const V3_ASSETS_MAX_IDS_PER_REQUEST = 120;
+
+/** Max concurrent `/v3/assets` chunk requests (same default scale as balance middleware). */
+const V3_ASSETS_FETCH_CONCURRENCY = 3;
+
 const MIN_TOKEN_OCCURRENCES = 3;
 
 const log = createModuleLogger(projectLogger, CONTROLLER_NAME);
@@ -243,20 +250,38 @@ export class TokenDataSource {
       }
 
       try {
-        // Use ApiPlatformClient for fetching asset metadata
-        // API returns an array with assetId as a property on each item
-        const metadataResponse = await this.#apiClient.tokens.fetchV3Assets(
-          supportedAssetIds,
-          {
-            includeIconUrl: true,
-            includeMarketData: true,
-            includeMetadata: true,
-            includeLabels: true,
-            includeRwaData: true,
-            includeAggregators: true,
-            includeOccurrences: true,
-          },
+        const metadataQueryOptions = {
+          includeIconUrl: true,
+          includeMarketData: true,
+          includeMetadata: true,
+          includeLabels: true,
+          includeRwaData: true,
+          includeAggregators: true,
+          includeOccurrences: true,
+        };
+
+        // API returns an array with assetId as a property on each item.
+        // Request in chunks to stay within the per-request asset ID limit.
+        const chunks: string[][] = [];
+        for (
+          let i = 0;
+          i < supportedAssetIds.length;
+          i += V3_ASSETS_MAX_IDS_PER_REQUEST
+        ) {
+          chunks.push(
+            supportedAssetIds.slice(i, i + V3_ASSETS_MAX_IDS_PER_REQUEST),
+          );
+        }
+
+        const limit = pLimit(V3_ASSETS_FETCH_CONCURRENCY);
+        const chunkResponses = await Promise.all(
+          chunks.map((chunk) =>
+            limit(() =>
+              this.#apiClient.tokens.fetchV3Assets(chunk, metadataQueryOptions),
+            ),
+          ),
         );
+        const metadataResponse = chunkResponses.flat();
 
         response.assetsInfo ??= {};