Issue MetaMask#5640 external accounts implemented

app/_locales/en/messages.json

@@ -11,6 +11,16 @@
   "exposeDescription": {
     "message": "Expose accounts to the current website. Useful for legacy dapps."
   },
+  "external": {
+    "message": "External"
+  },
+  "externalAcc": {
+    "message": "External Account",
+    "description": "select this for entering external account without password"
+  },
+  "externalAccountMsg": {
+    "message": "External accounts will not be associated with your originally created MetaMask account seedphrase. When you want to confirm a transaction with external account, Metamask will provide transaction details and expects a valid signature from external signer app."
+  },
   "confirmExpose": {
     "message": "Are you sure you want to expose your accounts to the current website?"
   },
@@ -663,6 +673,15 @@
   "invalidSeedPhrase": {
     "message": "Invalid seed phrase"
   },
+  "invalidSignature": {
+    "message": "Invalid signature"
+  },
+  "invalidSignatureLength": {
+    "message": "Length should be 130 chars."
+  },
+  "invalidSignatureChar": {
+    "message": "Invalid character in signature."
+  },
   "jsonFail": {
     "message": "Something went wrong. Please make sure your JSON file is properly formatted."
   },
@@ -916,6 +935,10 @@
     "message": "Paste your private key string here:",
     "description": "For importing an account from a private key"
   },
+  "pasteExternalAccount": {
+    "message": "Paste your external account address here:",
+    "description": "For importing an external account from account number"
+  },
   "pasteSeed": {
     "message": "Paste your seed phrase here!"
   },
@@ -974,6 +997,9 @@
   "recipientAddress": {
     "message": "Recipient Address"
   },
+  "signature": {
+    "message": "Signature"
+  },
   "refundAddress": {
     "message": "Your Refund Address"
   },

app/scripts/metamask-controller.js

@@ -155,7 +155,10 @@ module.exports = class MetamaskController extends EventEmitter {
     })
 
     // key mgmt
-    const additionalKeyrings = [TrezorKeyring, LedgerBridgeKeyring]
+    const additionalKeyrings = [
+      TrezorKeyring,
+      LedgerBridgeKeyring,
+    ]
     this.keyringController = new KeyringController({
       keyringTypes: additionalKeyrings,
       initState: initState.KeyringController,
@@ -401,6 +404,7 @@ module.exports = class MetamaskController extends EventEmitter {
       resetAccount: nodeify(this.resetAccount, this),
       removeAccount: nodeify(this.removeAccount, this),
       importAccountWithStrategy: nodeify(this.importAccountWithStrategy, this),
+      addExtAccount: nodeify(this.addExtAccount, this),
 
       // hardware wallets
       connectHardware: nodeify(this.connectHardware, this),
@@ -438,6 +442,7 @@ module.exports = class MetamaskController extends EventEmitter {
       createNewVaultAndRestore: nodeify(this.createNewVaultAndRestore, this),
       addNewKeyring: nodeify(keyringController.addNewKeyring, keyringController),
       exportAccount: nodeify(keyringController.exportAccount, keyringController),
+      updateExternalSign: nodeify(keyringController.updateExternalSign, keyringController),
 
       // txController
       cancelTransaction: nodeify(txController.cancelTransaction, txController),
@@ -877,6 +882,23 @@ module.exports = class MetamaskController extends EventEmitter {
     await this.preferencesController.setSelectedAddress(accounts[0])
   }
 
+  /**
+   * Creates and external account and adds it to a newly created
+   * ExternalAccountKeyring.
+   *
+   * @param  {string} address - A valid Ethereum address string.
+   */
+  async addExtAccount (address) {
+    if (!ethUtil.isValidAddress(address)) throw new Error('Address is invalid.')
+    const keyring = await this.keyringController.addNewKeyring('External Account', [ address ])
+    const accounts = await keyring.getAccounts()
+    // update accounts in preferences controller
+    const allAccounts = await this.keyringController.getAccounts()
+    this.preferencesController.setAddresses(allAccounts)
+    // set new account as selected
+    await this.preferencesController.setSelectedAddress(accounts[0])
+  }
+
   // ---------------------------------------------------------------------------
   // Identity Management (signature operations)