account tracker - update accounts from balanceChecker contract (#6181)

* account tracker - update accounts from balanceChecker contract

* fall back to getBalance if the contract query fails

3 files changed, 70 insertions, 3 deletions

diff --git a/app/scripts/controllers/network/contract-addresses.js b/app/scripts/controllers/network/contract-addresses.js
new file mode 100644
index 000000000..5cd7da1d0
--- /dev/null
+++ b/app/scripts/controllers/network/contract-addresses.js
@@ -0,0 +1,11 @@
+const SINGLE_CALL_BALANCES_ADDRESS = '0xb1f8e55c7f64d203c1400b9d8555d050f94adf39'
+const SINGLE_CALL_BALANCES_ADDRESS_RINKEBY = '0x9f510b19f1ad66f0dcf6e45559fab0d6752c1db7'
+const SINGLE_CALL_BALANCES_ADDRESS_ROPSTEN = '0xb8e671734ce5c8d7dfbbea5574fa4cf39f7a54a4'
+const SINGLE_CALL_BALANCES_ADDRESS_KOVAN = '0xb1d3fbb2f83aecd196f474c16ca5d9cffa0d0ffc'
+
+module.exports = {
+    SINGLE_CALL_BALANCES_ADDRESS,
+    SINGLE_CALL_BALANCES_ADDRESS_RINKEBY,
+    SINGLE_CALL_BALANCES_ADDRESS_ROPSTEN,
+    SINGLE_CALL_BALANCES_ADDRESS_KOVAN,
+}
diff --git a/app/scripts/lib/account-tracker.js b/app/scripts/lib/account-tracker.js
index 2e9340018..24c5ef7ee 100644
--- a/app/scripts/lib/account-tracker.js
+++ b/app/scripts/lib/account-tracker.js
@@ -11,6 +11,12 @@ const EthQuery = require('eth-query')
 const ObservableStore = require('obs-store')
 const log = require('loglevel')
 const pify = require('pify')
+const Web3 = require('web3')
+const SINGLE_CALL_BALANCES_ABI = require('single-call-balance-checker-abi')
+
+const { bnToHex } = require('./util')
+const { MAINNET_CODE, RINKEYBY_CODE, ROPSTEN_CODE, KOVAN_CODE } = require('../controllers/network/enums')
+const { SINGLE_CALL_BALANCES_ADDRESS, SINGLE_CALL_BALANCES_ADDRESS_RINKEBY, SINGLE_CALL_BALANCES_ADDRESS_ROPSTEN, SINGLE_CALL_BALANCES_ADDRESS_KOVAN } = require('../controllers/network/contract-addresses')
 
 
 class AccountTracker {
@@ -50,6 +56,9 @@ class AccountTracker {
     })
     // bind function for easier listener syntax
     this._updateForBlock = this._updateForBlock.bind(this)
+    this.network = opts.network
+
+    this.web3 = new Web3(this._provider)
   }
 
   start () {
@@ -116,7 +125,7 @@ class AccountTracker {
     this.store.updateState({ accounts })
     // fetch balances for the accounts if there is block number ready
     if (!this._currentBlockNumber) return
-    addresses.forEach(address => this._updateAccount(address))
+    this._updateAccounts()
   }
 
   /**
@@ -161,7 +170,8 @@ class AccountTracker {
   }
 
   /**
-   * Calls this._updateAccount for each account in this.store
+   * balanceChecker is deployed on main eth (test)nets and requires a single call
+   * for all other networks, calls this._updateAccount for each account in this.store
    *
    * @returns {Promise} after all account balances updated
    *
@@ -169,7 +179,28 @@ class AccountTracker {
   async _updateAccounts () {
     const accounts = this.store.getState().accounts
     const addresses = Object.keys(accounts)
-    await Promise.all(addresses.map(this._updateAccount.bind(this)))
+    const currentNetwork = parseInt(this.network.getNetworkState())
+
+    switch (currentNetwork) {
+      case MAINNET_CODE:
+      await this._updateAccountsViaBalanceChecker(addresses, SINGLE_CALL_BALANCES_ADDRESS)
+      break
+
+      case RINKEYBY_CODE:
+      await this._updateAccountsViaBalanceChecker(addresses, SINGLE_CALL_BALANCES_ADDRESS_RINKEBY)
+      break
+
+      case ROPSTEN_CODE:
+      await this._updateAccountsViaBalanceChecker(addresses, SINGLE_CALL_BALANCES_ADDRESS_ROPSTEN)
+      break
+
+      case KOVAN_CODE:
+      await this._updateAccountsViaBalanceChecker(addresses, SINGLE_CALL_BALANCES_ADDRESS_KOVAN)
+      break
+
+      default:
+      await Promise.all(addresses.map(this._updateAccount.bind(this)))
+    }
   }
 
   /**
@@ -192,6 +223,30 @@ class AccountTracker {
     this.store.updateState({ accounts })
   }
 
+  /**
+   * Updates current address balances from balanceChecker deployed contract instance
+   * @param {*} addresses
+   * @param {*} deployedContractAddress
+   */
+  async _updateAccountsViaBalanceChecker (addresses, deployedContractAddress) {
+    const accounts = this.store.getState().accounts
+    this.web3.setProvider(this._provider)
+    const ethContract = this.web3.eth.contract(SINGLE_CALL_BALANCES_ABI).at(deployedContractAddress)
+    const ethBalance = ['0x0']
+
+    ethContract.balances(addresses, ethBalance, (error, result) => {
+      if (error) {
+        log.warn(`MetaMask - Account Tracker single call balance fetch failed`, error)
+        return Promise.all(addresses.map(this._updateAccount.bind(this)))
+      }
+      addresses.forEach((address, index) => {
+        const balance = bnToHex(result[index])
+        accounts[address] = { address, balance }
+      })
+      this.store.updateState({ accounts })
+    })
+  }
+
 }
 
 module.exports = AccountTracker
diff --git a/app/scripts/metamask-controller.js b/app/scripts/metamask-controller.js
index b75f95d01..6555f179d 100644
--- a/app/scripts/metamask-controller.js
+++ b/app/scripts/metamask-controller.js
@@ -133,6 +133,7 @@ module.exports = class MetamaskController extends EventEmitter {
     this.accountTracker = new AccountTracker({
       provider: this.provider,
       blockTracker: this.blockTracker,
+      network: this.networkController,
     })
 
     // start and stop polling for balances based on activeControllerConnections