Feature: Subscription support

app/scripts/controllers/network/createInfuraClient.js

@@ -1,5 +1,6 @@
 const mergeMiddleware = require('json-rpc-engine/src/mergeMiddleware')
-const createBlockReEmitMiddleware = require('eth-json-rpc-middleware/block-reemit')
+const createBlockReRefMiddleware = require('eth-json-rpc-middleware/block-ref')
+const createRetryOnEmptyMiddleware = require('eth-json-rpc-middleware/retryOnEmpty')
 const createBlockCacheMiddleware = require('eth-json-rpc-middleware/block-cache')
 const createInflightMiddleware = require('eth-json-rpc-middleware/inflight-cache')
 const createBlockTrackerInspectorMiddleware = require('eth-json-rpc-middleware/block-tracker-inspector')
@@ -11,13 +12,14 @@ module.exports = createInfuraClient
 
 function createInfuraClient ({ network }) {
   const infuraMiddleware = createInfuraMiddleware({ network })
-  const blockProvider = providerFromMiddleware(infuraMiddleware)
-  const blockTracker = new BlockTracker({ provider: blockProvider })
+  const infuraProvider = providerFromMiddleware(infuraMiddleware)
+  const blockTracker = new BlockTracker({ provider: infuraProvider })
 
   const networkMiddleware = mergeMiddleware([
     createBlockCacheMiddleware({ blockTracker }),
     createInflightMiddleware(),
-    createBlockReEmitMiddleware({ blockTracker, provider: blockProvider }),
+    createBlockReRefMiddleware({ blockTracker, provider: infuraProvider }),
+    createRetryOnEmptyMiddleware({ blockTracker, provider: infuraProvider }),
     createBlockTrackerInspectorMiddleware({ blockTracker }),
     infuraMiddleware,
   ])

app/scripts/controllers/network/createJsonRpcClient.js

@@ -1,6 +1,6 @@
 const mergeMiddleware = require('json-rpc-engine/src/mergeMiddleware')
 const createFetchMiddleware = require('eth-json-rpc-middleware/fetch')
-const createBlockRefMiddleware = require('eth-json-rpc-middleware/block-ref')
+const createBlockRefRewriteMiddleware = require('eth-json-rpc-middleware/block-ref-rewrite')
 const createBlockCacheMiddleware = require('eth-json-rpc-middleware/block-cache')
 const createInflightMiddleware = require('eth-json-rpc-middleware/inflight-cache')
 const createBlockTrackerInspectorMiddleware = require('eth-json-rpc-middleware/block-tracker-inspector')
@@ -15,7 +15,7 @@ function createJsonRpcClient ({ rpcUrl }) {
   const blockTracker = new BlockTracker({ provider: blockProvider })
 
   const networkMiddleware = mergeMiddleware([
-    createBlockRefMiddleware({ blockTracker }),
+    createBlockRefRewriteMiddleware({ blockTracker }),
     createBlockCacheMiddleware({ blockTracker }),
     createInflightMiddleware(),
     createBlockTrackerInspectorMiddleware({ blockTracker }),

app/scripts/controllers/network/createLocalhostClient.js

@@ -1,6 +1,6 @@
 const mergeMiddleware = require('json-rpc-engine/src/mergeMiddleware')
 const createFetchMiddleware = require('eth-json-rpc-middleware/fetch')
-const createBlockRefMiddleware = require('eth-json-rpc-middleware/block-ref')
+const createBlockRefRewriteMiddleware = require('eth-json-rpc-middleware/block-ref-rewrite')
 const createBlockTrackerInspectorMiddleware = require('eth-json-rpc-middleware/block-tracker-inspector')
 const providerFromMiddleware = require('eth-json-rpc-middleware/providerFromMiddleware')
 const BlockTracker = require('eth-block-tracker')
@@ -13,7 +13,7 @@ function createLocalhostClient () {
   const blockTracker = new BlockTracker({ provider: blockProvider, pollingInterval: 1000 })
 
   const networkMiddleware = mergeMiddleware([
-    createBlockRefMiddleware({ blockTracker }),
+    createBlockRefRewriteMiddleware({ blockTracker }),
     createBlockTrackerInspectorMiddleware({ blockTracker }),
     fetchMiddleware,
   ])

app/scripts/inpage.js

@@ -5,6 +5,7 @@ const log = require('loglevel')
 const LocalMessageDuplexStream = require('post-message-stream')
 const setupDappAutoReload = require('./lib/auto-reload.js')
 const MetamaskInpageProvider = require('metamask-inpage-provider')
+
 restoreContextAfterImports()
 
 log.setDefaultLevel(process.env.METAMASK_DEBUG ? 'debug' : 'warn')
@@ -44,7 +45,15 @@ inpageProvider.enable = function (options = {}) {
   })
 }
 
-window.ethereum = inpageProvider
+// Work around for web3@1.0 deleting the bound `sendAsync` but not the unbound
+// `sendAsync` method on the prototype, causing `this` reference issues with drizzle
+const proxiedInpageProvider = new Proxy(inpageProvider, {
+  // straight up lie that we deleted the property so that it doesnt
+  // throw an error in strict mode
+  deleteProperty: () => true,
+})
+
+window.ethereum = proxiedInpageProvider
 
 //
 // setup web3
@@ -58,7 +67,7 @@ if (typeof window.web3 !== 'undefined') {
      and try again.`)
 }
 
-var web3 = new Web3(inpageProvider)
+var web3 = new Web3(proxiedInpageProvider)
 web3.setProvider = function () {
   log.debug('MetaMask - overrode web3.setProvider')
 }

app/scripts/metamask-controller.js

@@ -15,6 +15,7 @@ const RpcEngine = require('json-rpc-engine')
 const debounce = require('debounce')
 const createEngineStream = require('json-rpc-middleware-stream/engineStream')
 const createFilterMiddleware = require('eth-json-rpc-filters')
+const createSubscriptionManager = require('eth-json-rpc-filters/subscriptionManager')
 const createOriginMiddleware = require('./lib/createOriginMiddleware')
 const createLoggerMiddleware = require('./lib/createLoggerMiddleware')
 const createProviderMiddleware = require('./lib/createProviderMiddleware')
@@ -1246,24 +1247,33 @@ module.exports = class MetamaskController extends EventEmitter {
   setupProviderConnection (outStream, origin) {
     // setup json rpc engine stack
     const engine = new RpcEngine()
+    const provider = this.provider
+    const blockTracker = this.blockTracker
 
     // create filter polyfill middleware
-    const filterMiddleware = createFilterMiddleware({
-      provider: this.provider,
-      blockTracker: this.blockTracker,
-    })
+    const filterMiddleware = createFilterMiddleware({ provider, blockTracker })
+    // create subscription polyfill middleware
+    const subscriptionManager = createSubscriptionManager({ provider, blockTracker })
+    subscriptionManager.events.on('notification', (message) => engine.emit('notification', message))
 
+    // metadata
     engine.push(createOriginMiddleware({ origin }))
     engine.push(createLoggerMiddleware({ origin }))
+    // filter and subscription polyfills
     engine.push(filterMiddleware)
+    engine.push(subscriptionManager.middleware)
+    // watch asset
     engine.push(this.preferencesController.requestWatchAsset.bind(this.preferencesController))
+    // sign typed data middleware
     engine.push(this.createTypedDataMiddleware('eth_signTypedData', 'V1').bind(this))
     engine.push(this.createTypedDataMiddleware('eth_signTypedData_v1', 'V1').bind(this))
     engine.push(this.createTypedDataMiddleware('eth_signTypedData_v3', 'V3', true).bind(this))
-    engine.push(createProviderMiddleware({ provider: this.provider }))
+    // forward to metamask primary provider
+    engine.push(createProviderMiddleware({ provider }))
 
     // setup connection
     const providerStream = createEngineStream({ engine })
+
     pump(
       outStream,
       providerStream,