Add createCancelTransaction method

app/scripts/controllers/transactions/enums.js

@@ -0,0 +1,12 @@
+const TRANSACTION_TYPE_CANCEL = 'cancel'
+const TRANSACTION_TYPE_RETRY = 'retry'
+const TRANSACTION_TYPE_STANDARD = 'standard'
+
+const TRANSACTION_STATUS_APPROVED = 'approved'
+
+module.exports = {
+  TRANSACTION_TYPE_CANCEL,
+  TRANSACTION_TYPE_RETRY,
+  TRANSACTION_TYPE_STANDARD,
+  TRANSACTION_STATUS_APPROVED,
+}

app/scripts/controllers/transactions/index.js

@@ -11,6 +11,14 @@ const txUtils = require('./lib/util')
 const cleanErrorStack = require('../../lib/cleanErrorStack')
 const log = require('loglevel')
 const recipientBlacklistChecker = require('./lib/recipient-blacklist-checker')
+const {
+  TRANSACTION_TYPE_CANCEL,
+  TRANSACTION_TYPE_RETRY,
+  TRANSACTION_TYPE_STANDARD,
+  TRANSACTION_STATUS_APPROVED,
+} = require('./enums')
+
+const { hexToBn, bnToHex } = require('../../lib/util')
 
 /**
   Transaction Controller is an aggregate of sub-controllers and trackers
@@ -160,7 +168,10 @@ class TransactionController extends EventEmitter {
     const normalizedTxParams = txUtils.normalizeTxParams(txParams)
     txUtils.validateTxParams(normalizedTxParams)
     // construct txMeta
-    let txMeta = this.txStateManager.generateTxMeta({ txParams: normalizedTxParams })
+    let txMeta = this.txStateManager.generateTxMeta({
+      txParams: normalizedTxParams,
+      type: TRANSACTION_TYPE_STANDARD,
+    })
     this.addTx(txMeta)
     this.emit('newUnapprovedTx', txMeta)
 
@@ -214,12 +225,46 @@ class TransactionController extends EventEmitter {
       txParams: originalTxMeta.txParams,
       lastGasPrice,
       loadingDefaults: false,
+      type: TRANSACTION_TYPE_RETRY,
     })
     this.addTx(txMeta)
     this.emit('newUnapprovedTx', txMeta)
     return txMeta
   }
 
+  /**
+   * Creates a new approved transaction to attempt to cancel a previously submitted transaction. The
+   * new transaction contains the same nonce as the previous, is a basic ETH transfer of 0x value to
+   * the sender's address, and has a higher gasPrice than that of the previous transaction.
+   * @param {number} originalTxId - the id of the txMeta that you want to attempt to cancel
+   * @param {string=} customGasPrice - the hex value to use for the cancel transaction
+   * @returns {txMeta}
+   */
+  async createCancelTransaction (originalTxId, customGasPrice) {
+    const originalTxMeta = this.txStateManager.getTx(originalTxId)
+    const { txParams } = originalTxMeta
+    const { gasPrice: lastGasPrice, from, nonce } = txParams
+    const newGasPrice = customGasPrice || bnToHex(hexToBn(lastGasPrice).mul(1.1))
+    const newTxMeta = this.txStateManager.generateTxMeta({
+      txParams: {
+        from,
+        to: from,
+        nonce,
+        gas: '0x5208',
+        value: '0x0',
+        gasPrice: newGasPrice,
+      },
+      lastGasPrice,
+      loadingDefaults: false,
+      status: TRANSACTION_STATUS_APPROVED,
+      type: TRANSACTION_TYPE_CANCEL,
+    })
+
+    this.addTx(newTxMeta)
+    await this.approveTransaction(newTxMeta.id)
+    return newTxMeta
+  }
+
   /**
   updates the txMeta in the txStateManager
   @param txMeta {Object} - the updated txMeta
@@ -393,7 +438,7 @@ class TransactionController extends EventEmitter {
     })
 
     this.txStateManager.getFilteredTxList({
-      status: 'approved',
+      status: TRANSACTION_STATUS_APPROVED,
     }).forEach((txMeta) => {
       const txSignError = new Error('Transaction found as "approved" during boot - possibly stuck during signing')
       this.txStateManager.setTxStatusFailed(txMeta.id, txSignError)

app/scripts/metamask-controller.js

@@ -407,6 +407,7 @@ module.exports = class MetamaskController extends EventEmitter {
       updateTransaction: nodeify(txController.updateTransaction, txController),
       updateAndApproveTransaction: nodeify(txController.updateAndApproveTransaction, txController),
       retryTransaction: nodeify(this.retryTransaction, this),
+      createCancelTransaction: nodeify(this.createCancelTransaction, this),
       getFilteredTxList: nodeify(txController.getFilteredTxList, txController),
       isNonceTaken: nodeify(txController.isNonceTaken, txController),
       estimateGas: nodeify(this.estimateGas, this),
@@ -1109,6 +1110,19 @@ module.exports = class MetamaskController extends EventEmitter {
     return state
   }
 
+  /**
+   * Allows a user to attempt to cancel a previously submitted transaction by creating a new
+   * transaction.
+   * @param {number} originalTxId - the id of the txMeta that you want to attempt to cancel
+   * @param {string=} customGasPrice - the hex value to use for the cancel transaction
+   * @returns {object} MetaMask state
+   */
+  async createCancelTransaction (originalTxId, customGasPrice, cb) {
+    await this.txController.createCancelTransaction(originalTxId, customGasPrice)
+    const state = await this.getState()
+    return state
+  }
+
   estimateGas (estimateGasParams) {
     return new Promise((resolve, reject) => {
       return this.txController.txGasUtil.query.estimateGas(estimateGasParams, (err, res) => {

ui/app/actions.js

@@ -315,6 +315,8 @@ var actions = {
   CLEAR_PENDING_TOKENS: 'CLEAR_PENDING_TOKENS',
   setPendingTokens,
   clearPendingTokens,
+
+  createCancelTransaction,
 }
 
 module.exports = actions
@@ -1766,6 +1768,29 @@ function retryTransaction (txId) {
   }
 }
 
+function createCancelTransaction (txId, customGasPrice) {
+  log.debug('background.cancelTransaction')
+  let newTxId
+
+  return dispatch => {
+    return new Promise((resolve, reject) => {
+      background.createCancelTransaction(txId, customGasPrice, (err, newState) => {
+        if (err) {
+          dispatch(actions.displayWarning(err.message))
+          reject(err)
+        }
+
+        const { selectedAddressTxList } = newState
+        const { id } = selectedAddressTxList[selectedAddressTxList.length - 1]
+        newTxId = id
+        resolve(newState)
+      })
+    })
+    .then(newState => dispatch(actions.updateMetamaskState(newState)))
+    .then(() => newTxId)
+  }
+}
+
 //
 // config
 //