feat: add optional createAccounts method based on KeyringV2

packages/keyring-api/CHANGELOG.md

@@ -9,6 +9,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Add `Keyring.createAccounts` optional method ([#448](https://github.com/MetaMask/accounts/pull/448))
+  - This method is part of the keyring v2 specification and set as optional for backwards compatibility.
+  - This method can be used to create one or more accounts using the new keyring v2 account creation typed options.
 - Add support for account derivations using range of indices in `KeyringV2` ([#451](https://github.com/MetaMask/accounts/pull/451))
   - Add `bip44:derive-index-range` capability to `KeyringCapabilities`.
   - Add `AccountCreationType.Bip44DeriveIndexRange` and `CreateAccountBip44DeriveIndexRangeOptions`.

packages/keyring-api/src/api/keyring.ts

@@ -13,6 +13,7 @@ import type { Paginated, Pagination } from './pagination';
 import type { KeyringRequest } from './request';
 import type { KeyringResponse } from './response';
 import type { Transaction } from './transaction';
+import type { CreateAccountOptions } from './v2';
 
 /**
  * Keyring interface.
@@ -56,6 +57,19 @@ export type Keyring = {
     options?: Record<string, Json> & MetaMaskOptions,
   ): Promise<KeyringAccount>;
 
+  /**
+   * Creates one or more new accounts according to the provided options.
+   *
+   * Deterministic account creation MUST be idempotent, meaning that for
+   * deterministic algorithms, like BIP-44, calling this method with the same
+   * options should always return the same accounts, even if the accounts
+   * already exist in the keyring.
+   *
+   * @param options - Options describing how to create the account(s).
+   * @returns A promise that resolves to an array of the created account objects.
+   */
+  createAccounts?(options: CreateAccountOptions): Promise<KeyringAccount[]>;
+
   /**
    * Lists the assets of an account (fungibles and non-fungibles) represented
    * by their respective CAIP-19:

packages/keyring-api/src/rpc.ts

@@ -28,6 +28,7 @@ import {
   PaginationStruct,
   CaipAccountIdStruct,
   DiscoveredAccountStruct,
+  CreateAccountOptionsStruct,
 } from './api';
 
 /**
@@ -36,6 +37,7 @@ import {
 export enum KeyringRpcMethod {
   // Account management
   CreateAccount = 'keyring_createAccount',
+  CreateAccounts = 'keyring_createAccounts',
   DeleteAccount = 'keyring_deleteAccount',
   DiscoverAccounts = 'keyring_discoverAccounts',
   ExportAccount = 'keyring_exportAccount',
@@ -126,6 +128,23 @@ export const CreateAccountResponseStruct = KeyringAccountStruct;
 
 export type CreateAccountResponse = Infer<typeof CreateAccountResponseStruct>;
 
+// ----------------------------------------------------------------------------
+// Create accounts
+
+export const CreateAccountsRequestStruct = object({
+  ...CommonHeader,
+  method: literal('keyring_createAccounts'),
+  params: object({
+    options: CreateAccountOptionsStruct,
+  }),
+});
+
+export type CreateAccountsRequest = Infer<typeof CreateAccountsRequestStruct>;
+
+export const CreateAccountsResponseStruct = array(KeyringAccountStruct);
+
+export type CreateAccountsResponse = Infer<typeof CreateAccountsResponseStruct>;
+
 // ----------------------------------------------------------------------------
 // Set selected accounts
 

packages/keyring-snap-bridge/CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Add `SnapKeyring.createAccounts` method ([#448](https://github.com/MetaMask/accounts/pull/448))
+  - This method can be used to create one or more accounts using the new keyring v2 account creation typed options.
+
 ### Changed
 
 - Bump `@metamask/snaps-controllers` from `^14.0.1` to `^17.2.0` ([#422](https://github.com/MetaMask/accounts/pull/422))

packages/keyring-snap-bridge/src/SnapKeyring.test.ts

@@ -10,6 +10,7 @@ import type {
   AccountTransactionsUpdatedEventPayload,
   AccountAssetListUpdatedEventPayload,
   MetaMaskOptions,
+  CreateAccountOptions,
 } from '@metamask/keyring-api';
 import {
   EthScope,
@@ -28,6 +29,7 @@ import {
   TrxScope,
   TrxMethod,
   TrxAccountType,
+  AccountCreationType,
 } from '@metamask/keyring-api';
 import { SnapManageAccountsMethod } from '@metamask/keyring-snap-sdk';
 import type { JsonRpcRequest } from '@metamask/keyring-utils';
@@ -2520,6 +2522,224 @@ describe('SnapKeyring', () => {
     });
   });
 
+  describe('createAccounts', () => {
+    const newAccount1 = {
+      ...newEthEoaAccount,
+      id: 'aa11bb22-cc33-4d44-8e55-ff6677889900',
+      address: '0xaabbccddee00112233445566778899aabbccddee',
+    };
+    const newAccount2 = {
+      ...newEthEoaAccount,
+      id: 'bb11bb22-cc33-4d44-9e55-ff6677889900',
+      address: '0xbbccddee00112233445566778899aabbccddeeff',
+    };
+    const newAccount3 = {
+      ...newEthEoaAccount,
+      id: 'cc11bb22-cc33-4d44-ae55-ff6677889900',
+      address: '0xccddee00112233445566778899aabbccddee0011',
+    };
+
+    const entropySource = '01JQCAKR17JARQXZ0NDP760N1K';
+
+    const snapMetadata = {
+      manifest: {
+        proposedName: 'snap-name',
+      },
+      id: snapId,
+      enabled: true,
+    };
+
+    it('creates multiple accounts', async () => {
+      mockCallbacks.addAccount.mockClear();
+      mockCallbacks.saveState.mockClear();
+
+      mockMessenger.get.mockReturnValue(snapMetadata);
+
+      const accountsToCreate = [newAccount1, newAccount2, newAccount3];
+
+      mockMessengerHandleRequest({
+        [KeyringRpcMethod.CreateAccounts]: async () => {
+          // Unlike createAccount, createAccounts does NOT emit AccountCreated events
+          // for each account. It returns all accounts directly.
+          return accountsToCreate;
+        },
+      });
+
+      const options: CreateAccountOptions = {
+        type: AccountCreationType.Bip44DeriveIndexRange,
+        entropySource,
+        range: {
+          from: 0,
+          to: 2,
+        },
+      };
+      const result = await keyring.createAccounts(snapId, options);
+
+      expect(mockMessenger.handleRequest).toHaveBeenLastCalledWith(
+        mockKeyringRpcRequest(KeyringRpcMethod.CreateAccounts, options),
+      );
+
+      // Verify all accounts were returned
+      expect(result).toStrictEqual(accountsToCreate);
+
+      // Verify all accounts were added to the internal state
+      for (const account of accountsToCreate) {
+        expect(keyring.getAccountByAddress(account.address)).toMatchObject({
+          ...account,
+          metadata: expect.objectContaining({
+            snap: expect.objectContaining({
+              id: snapId,
+            }),
+          }),
+        });
+      }
+
+      // Verify state was saved once after adding all accounts
+      expect(mockCallbacks.saveState).toHaveBeenCalled();
+
+      // IMPORTANT: Unlike createAccount, createAccounts does NOT call addAccount callback
+      // because accounts are created in batch
+      expect(mockCallbacks.addAccount).not.toHaveBeenCalled();
+    });
+
+    it('creates a single account through createAccounts', async () => {
+      mockCallbacks.addAccount.mockClear();
+      mockCallbacks.saveState.mockClear();
+
+      mockMessenger.get.mockReturnValue(snapMetadata);
+
+      const accountToCreate = [newAccount1];
+
+      mockMessengerHandleRequest({
+        [KeyringRpcMethod.CreateAccounts]: async () => accountToCreate,
+      });
+
+      const options: CreateAccountOptions = {
+        type: AccountCreationType.Bip44DeriveIndex,
+        groupIndex: 0,
+        entropySource,
+      };
+      const result = await keyring.createAccounts(snapId, options);
+
+      expect(mockMessenger.handleRequest).toHaveBeenLastCalledWith(
+        mockKeyringRpcRequest(KeyringRpcMethod.CreateAccounts, options),
+      );
+
+      expect(result).toStrictEqual(accountToCreate);
+      expect(result).toHaveLength(1);
+
+      // Verify the account was added to the internal state
+      expect(keyring.getAccountByAddress(newAccount1.address)).toMatchObject({
+        ...newAccount1,
+        metadata: expect.objectContaining({
+          snap: expect.objectContaining({
+            id: snapId,
+          }),
+        }),
+      });
+
+      expect(mockCallbacks.saveState).toHaveBeenCalled();
+      expect(mockCallbacks.addAccount).not.toHaveBeenCalled();
+    });
+
+    it('creates accounts with custom options', async () => {
+      mockCallbacks.addAccount.mockClear();
+      mockCallbacks.saveState.mockClear();
+
+      const accountsToCreate = [newAccount1, newAccount2];
+      const options: CreateAccountOptions = {
+        type: AccountCreationType.Custom,
+      };
+
+      mockMessengerHandleRequest({
+        [KeyringRpcMethod.CreateAccounts]: async () => accountsToCreate,
+      });
+
+      const result = await keyring.createAccounts(snapId, options);
+
+      expect(mockMessenger.handleRequest).toHaveBeenLastCalledWith(
+        mockKeyringRpcRequest(KeyringRpcMethod.CreateAccounts, options),
+      );
+
+      expect(result).toStrictEqual(accountsToCreate);
+      expect(mockCallbacks.saveState).toHaveBeenCalled();
+      expect(mockCallbacks.addAccount).not.toHaveBeenCalled();
+    });
+
+    it('handles empty response from Snap', async () => {
+      mockCallbacks.addAccount.mockClear();
+      mockCallbacks.saveState.mockClear();
+
+      mockMessengerHandleRequest({
+        [KeyringRpcMethod.CreateAccounts]: async () => [],
+      });
+
+      const options: CreateAccountOptions = {
+        type: AccountCreationType.Bip44DeriveIndex,
+        entropySource,
+        groupIndex: 0,
+      };
+      const result = await keyring.createAccounts(snapId, options);
+
+      expect(result).toStrictEqual([]);
+      expect(mockCallbacks.saveState).toHaveBeenCalled();
+      expect(mockCallbacks.addAccount).not.toHaveBeenCalled();
+    });
+
+    it('handles errors from Snap', async () => {
+      mockCallbacks.addAccount.mockClear();
+      mockCallbacks.saveState.mockClear();
+
+      const errorMessage = 'Failed to create accounts';
+
+      mockMessengerHandleRequest({
+        [KeyringRpcMethod.CreateAccounts]: async () => {
+          throw new Error(errorMessage);
+        },
+      });
+
+      const options: CreateAccountOptions = {
+        type: AccountCreationType.Bip44DeriveIndex,
+        entropySource,
+        groupIndex: 0,
+      };
+      await expect(keyring.createAccounts(snapId, options)).rejects.toThrow(
+        errorMessage,
+      );
+
+      // State should not be saved if account creation fails
+      expect(mockCallbacks.saveState).not.toHaveBeenCalled();
+      expect(mockCallbacks.addAccount).not.toHaveBeenCalled();
+    });
+
+    it('adds all accounts to the internal map with correct snapId', async () => {
+      mockCallbacks.addAccount.mockClear();
+      mockCallbacks.saveState.mockClear();
+
+      mockMessenger.get.mockReturnValue(snapMetadata);
+
+      const accountsToCreate = [newAccount1, newAccount2];
+
+      mockMessengerHandleRequest({
+        [KeyringRpcMethod.CreateAccounts]: async () => accountsToCreate,
+      });
+
+      const options: CreateAccountOptions = {
+        type: AccountCreationType.Bip44DeriveIndex,
+        entropySource,
+        groupIndex: 0,
+      };
+      await keyring.createAccounts(snapId, options);
+
+      // Verify each account is mapped to the correct snapId
+      for (const account of accountsToCreate) {
+        const createdAccount = keyring.getAccountByAddress(account.address);
+        expect(createdAccount).toBeDefined();
+        expect(createdAccount?.metadata.snap?.id).toBe(snapId);
+      }
+    });
+  });
+
   describe('resolveAccountAddress', () => {
     const scope = toCaipChainId(
       KnownCaipNamespace.Eip155,

packages/keyring-snap-bridge/src/SnapKeyring.ts

@@ -14,6 +14,7 @@ import type {
   CaipChainId,
   MetaMaskOptions,
   KeyringResponse,
+  CreateAccountOptions,
 } from '@metamask/keyring-api';
 import {
   EthBytesStruct,
@@ -891,6 +892,39 @@ export class SnapKeyring {
     });
   }
 
+  /**
+   * Create one or more accounts according to the provided options.
+   *
+   * This method supports batch account creation for BIP-44 derivation paths,
+   * allowing the creation of multiple accounts up to a specified maximum index.
+   *
+   * @param snapId - Snap ID to create the accounts for.
+   * @param options - Account creation options.
+   * @returns A promise that resolves to an array of the created account objects.
+   */
+  async createAccounts(
+    snapId: SnapId,
+    options: CreateAccountOptions,
+  ): Promise<KeyringAccount[]> {
+    const client = new KeyringInternalSnapClient({
+      messenger: this.#messenger,
+      snapId,
+    });
+
+    // Add each returned account to the internal accounts map.
+    // NOTE: This method DOES NOT rely on the `AccountCreated` event to add
+    // accounts to the keyring, since those accounts are created in batch.
+    const accounts = await client.createAccounts(options);
+    for (const account of accounts) {
+      this.#accounts.set(account.id, { account, snapId });
+    }
+
+    // Save the state after adding all accounts.
+    await this.#callbacks.saveState();
+
+    return accounts;
+  }
+
   /**
    * Checks if a Snap ID is known from the keyring.
    *

packages/keyring-snap-client/CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Add `KeyringClient.createAccounts` method ([#448](https://github.com/MetaMask/accounts/pull/448))
+  - This method can be used to create one or more accounts using the new keyring v2 account creation typed options.
+
 ## [8.1.1]
 
 ### Changed