network controller - small refactor

app/scripts/controllers/network.js

@@ -1,5 +1,6 @@
+const assert = require('assert')
 const EventEmitter = require('events')
-const MetaMaskProvider = require('web3-provider-engine/zero.js')
+const createMetamaskProvider = require('web3-provider-engine/zero.js')
 const ObservableStore = require('obs-store')
 const ComposedStore = require('obs-store/lib/composed')
 const extend = require('xtend')
@@ -18,13 +19,13 @@ module.exports = class NetworkController extends EventEmitter {
     this._proxy = createEventEmitterProxy()
 
     this.on('networkDidChange', this.lookupNetwork)
-    this.providerStore.subscribe((state) => this.switchNetwork({ rpcUrl: state.rpcTarget }))
+    this.providerStore.subscribe((state) => this._switchNetwork({ rpcUrl: state.rpcTarget }))
   }
 
-  initializeProvider (opts, providerContructor = MetaMaskProvider) {
-    this._baseProviderParams = opts
-    const provider = providerContructor(opts)
-    this._setProvider(provider)
+  initializeProvider (_providerParams) {
+    this._baseProviderParams = _providerParams
+    const rpcUrl = this.getCurrentRpcAddress()
+    this._configureStandardProvider({ rpcUrl })
     this._proxy.on('block', this._logBlock.bind(this))
     this._proxy.on('error', this.verifyNetwork.bind(this))
     this.ethQuery = new EthQuery(this._proxy)
@@ -32,15 +33,6 @@ module.exports = class NetworkController extends EventEmitter {
     return this._proxy
   }
 
-  switchNetwork (opts) {
-    this.setNetworkState('loading')
-    const providerParams = extend(this._baseProviderParams, opts)
-    this._baseProviderParams = providerParams
-    const provider = MetaMaskProvider(providerParams)
-    this._setProvider(provider)
-    this.emit('networkDidChange')
-  }
-
   verifyNetwork () {
     // Check network when restoring connectivity:
     if (this.isNetworkLoading()) this.lookupNetwork()
@@ -79,9 +71,12 @@ module.exports = class NetworkController extends EventEmitter {
     return this.getRpcAddressForType(provider.type)
   }
 
-  setProviderType (type) {
+  async setProviderType (type) {
+    assert(type !== 'rpc', `NetworkController.setProviderType - cannot connect by type "rpc"`)
+    // skip if type already matches
     if (type === this.getProviderConfig().type) return
     const rpcTarget = this.getRpcAddressForType(type)
+    assert(rpcTarget, `NetworkController - unknown rpc address for type "${type}"`)
     this.providerStore.updateState({ type, rpcTarget })
   }
 
@@ -94,6 +89,22 @@ module.exports = class NetworkController extends EventEmitter {
     return provider && provider.rpcTarget ? provider.rpcTarget : DEFAULT_RPC
   }
 
+  //
+  // Private
+  //
+
+  _switchNetwork (providerParams) {
+    this.setNetworkState('loading')
+    this._configureStandardProvider(providerParams)
+    this.emit('networkDidChange')
+  }
+
+  _configureStandardProvider(_providerParams) {
+    const providerParams = extend(this._baseProviderParams, _providerParams)
+    const provider = createMetamaskProvider(providerParams)
+    this._setProvider(provider)
+  }
+
   _setProvider (provider) {
     // collect old block tracker events
     const oldProvider = this._provider

app/scripts/metamask-controller.js

@@ -217,13 +217,11 @@ module.exports = class MetamaskController extends EventEmitter {
   //
 
   initializeProvider () {
-    return this.networkController.initializeProvider({
+    const providerOpts = {
       static: {
         eth_syncing: false,
         web3_clientVersion: `MetaMask/v${version}`,
       },
-      // rpc data source
-      rpcUrl: this.networkController.getCurrentRpcAddress(),
       originHttpHeaderKey: 'X-Metamask-Origin',
       // account mgmt
       getAccounts: (cb) => {
@@ -243,7 +241,9 @@ module.exports = class MetamaskController extends EventEmitter {
       processMessage: this.newUnsignedMessage.bind(this),
       // personal_sign msg signing
       processPersonalMessage: this.newUnsignedPersonalMessage.bind(this),
-    })
+    }
+    const providerProxy = this.networkController.initializeProvider(providerOpts)
+    return providerProxy
   }
 
   initPublicConfigStore () {
@@ -312,13 +312,14 @@ module.exports = class MetamaskController extends EventEmitter {
     const txController = this.txController
     const noticeController = this.noticeController
     const addressBookController = this.addressBookController
+    const networkController = this.networkController
 
     return {
       // etc
       getState: (cb) => cb(null, this.getState()),
-      setProviderType: this.networkController.setProviderType.bind(this.networkController),
       setCurrentCurrency: this.setCurrentCurrency.bind(this),
       markAccountsFound: this.markAccountsFound.bind(this),
+
       // coinbase
       buyEth: this.buyEth.bind(this),
       // shapeshift
@@ -333,12 +334,15 @@ module.exports = class MetamaskController extends EventEmitter {
       // vault management
       submitPassword: this.submitPassword.bind(this),
 
+      // network management
+      setProviderType: nodeify(networkController.setProviderType, networkController),
+      setDefaultRpc: nodeify(this.setDefaultRpc, this),
+      setCustomRpc: nodeify(this.setCustomRpc, this),
+
       // PreferencesController
       setSelectedAddress: nodeify(preferencesController.setSelectedAddress, preferencesController),
       addToken: nodeify(preferencesController.addToken, preferencesController),
       setCurrentAccountTab: nodeify(preferencesController.setCurrentAccountTab, preferencesController),
-      setDefaultRpc: nodeify(this.setDefaultRpc, this),
-      setCustomRpc: nodeify(this.setCustomRpc, this),
 
       // AddressController
       setAddressBook: nodeify(addressBookController.setAddressBook, addressBookController),
@@ -689,19 +693,19 @@ module.exports = class MetamaskController extends EventEmitter {
   createShapeShiftTx (depositAddress, depositType) {
     this.shapeshiftController.createShapeShiftTx(depositAddress, depositType)
   }
+
   // network
 
-  setDefaultRpc () {
-    this.networkController.setRpcTarget('http://localhost:8545')
-    return Promise.resolve('http://localhost:8545')
+  async setDefaultRpc () {
+    const localhost = 'http://localhost:8545'
+    this.networkController.setRpcTarget(localhost)
+    return localhost
   }
 
-  setCustomRpc (rpcTarget, rpcList) {
+  async setCustomRpc (rpcTarget, rpcList) {
     this.networkController.setRpcTarget(rpcTarget)
-
-    return this.preferencesController.updateFrequentRpcList(rpcTarget)
-    .then(() => {
-      return Promise.resolve(rpcTarget)
-    })
+    await this.preferencesController.updateFrequentRpcList(rpcTarget)
+    return rpcTarget
   }
+
 }