dapp reload - fixed disconnect detection via polling

app/scripts/contentscript.js

@@ -1,4 +1,5 @@
 const LocalMessageDuplexStream = require('post-message-stream')
+const PongStream = require('ping-pong-stream/pong')
 const PortStream = require('./lib/port-stream.js')
 const ObjectMultiplex = require('./lib/obj-multiplex')
 const extension = require('./lib/extension')
@@ -51,17 +52,20 @@ function setupStreams(){
   // forward communication plugin->inpage
   pageStream.pipe(pluginStream).pipe(pageStream)
 
-  // connect contentscript->inpage reload stream
+  // setup local multistream channels
   var mx = ObjectMultiplex()
   mx.on('error', console.error)
-  mx.pipe(pageStream)
-  var reloadStream = mx.createStream('reload')
-  reloadStream.on('error', console.error)
+  mx.pipe(pageStream).pipe(mx)
+
+  // connect ping stream
+  var pongStream = new PongStream({ objectMode: true })
+  pongStream.pipe(mx.createStream('pingpong')).pipe(pongStream)
+
+  // ignore unused channels (handled by background)
+  mx.ignoreStream('provider')
+  mx.ignoreStream('publicConfig')
+  mx.ignoreStream('reload')
 
-  // if we lose connection with the plugin, trigger tab refresh
-  pluginStream.on('close', function () {
-    reloadStream.write({ method: 'reset' })
-  })
 }
 
 function shouldInjectWeb3(){

app/scripts/inpage.js

@@ -2,6 +2,8 @@
 cleanContextForImports()
 require('web3/dist/web3.min.js')
 const LocalMessageDuplexStream = require('post-message-stream')
+const PingStream = require('ping-pong-stream/ping')
+const endOfStream = require('end-of-stream')
 const setupDappAutoReload = require('./lib/auto-reload.js')
 const MetamaskInpageProvider = require('./lib/inpage-provider.js')
 restoreContextAfterImports()
@@ -29,13 +31,22 @@ web3.setProvider = function () {
   console.log('MetaMask - overrode web3.setProvider')
 }
 console.log('MetaMask - injected web3')
+// export global web3, with usage-detection reload fn
+var triggerReload = setupDappAutoReload(web3)
 
-//
-// export global web3 with auto dapp reload
-//
-
+// listen for reset requests from metamask
 var reloadStream = inpageProvider.multiStream.createStream('reload')
-setupDappAutoReload(web3, reloadStream)
+reloadStream.once('data', triggerReload)
+
+// setup ping timeout autoreload
+// LocalMessageDuplexStream does not self-close, so reload if pingStream fails
+var pingChannel = inpageProvider.multiStream.createStream('pingpong')
+var pingStream = new PingStream({ objectMode: true })
+// wait for first successful reponse
+metamaskStream.once('data', function(){
+  pingStream.pipe(pingChannel).pipe(pingStream)
+})
+endOfStream(pingStream, triggerReload)
 
 // set web3 defaultAcount
 inpageProvider.publicConfigStore.subscribe(function (state) {

app/scripts/lib/auto-reload.js

@@ -3,7 +3,7 @@ const ensnare = require('ensnare')
 
 module.exports = setupDappAutoReload
 
-function setupDappAutoReload (web3, controlStream) {
+function setupDappAutoReload (web3) {
   // export web3 as a global, checking for usage
   var pageIsUsingWeb3 = false
   var resetWasRequested = false
@@ -16,19 +16,19 @@ function setupDappAutoReload (web3, controlStream) {
     global.web3 = web3
   }))
 
-  // listen for reset requests from metamask
-  controlStream.once('data', function () {
+  return handleResetRequest
+
+  function handleResetRequest() {
     resetWasRequested = true
     // ignore if web3 was not used
     if (!pageIsUsingWeb3) return
     // reload after short timeout
-    triggerReset()
-  })
-
-  // reload the page
-  function triggerReset () {
-    setTimeout(function () {
-      global.location.reload()
-    }, 500)
+    setTimeout(triggerReset, 500)
   }
+
 }
+
+// reload the page
+function triggerReset () {
+  global.location.reload()
+}

app/scripts/lib/inpage-provider.js

@@ -1,6 +1,6 @@
 const Streams = require('mississippi')
-const ObjectMultiplex = require('./obj-multiplex')
 const StreamProvider = require('web3-stream-provider')
+const ObjectMultiplex = require('./obj-multiplex')
 const RemoteStore = require('./remote-store.js').RemoteStore
 
 module.exports = MetamaskInpageProvider
@@ -11,8 +11,9 @@ function MetamaskInpageProvider (connectionStream) {
   // setup connectionStream multiplexing
   var multiStream = ObjectMultiplex()
   Streams.pipe(connectionStream, multiStream, connectionStream, function (err) {
-    console.warn('MetamaskInpageProvider - lost connection to MetaMask')
-    if (err) throw err
+    let warningMsg = 'MetamaskInpageProvider - lost connection to MetaMask'
+    if (err) warningMsg += '\n' + err.stack
+    console.warn(warningMsg)
   })
   self.multiStream = multiStream
 
@@ -20,16 +21,18 @@ function MetamaskInpageProvider (connectionStream) {
   var publicConfigStore = remoteStoreWithLocalStorageCache('MetaMask-Config')
   var storeStream = publicConfigStore.createStream()
   Streams.pipe(storeStream, multiStream.createStream('publicConfig'), storeStream, function (err) {
-    console.warn('MetamaskInpageProvider - lost connection to MetaMask publicConfig')
-    if (err) throw err
+    let warningMsg = 'MetamaskInpageProvider - lost connection to MetaMask publicConfig'
+    if (err) warningMsg += '\n' + err.stack
+    console.warn(warningMsg)
   })
   self.publicConfigStore = publicConfigStore
 
   // connect to async provider
   var asyncProvider = new StreamProvider()
   Streams.pipe(asyncProvider, multiStream.createStream('provider'), asyncProvider, function (err) {
-    console.warn('MetamaskInpageProvider - lost connection to MetaMask provider')
-    if (err) throw err
+    let warningMsg = 'MetamaskInpageProvider - lost connection to MetaMask provider'
+    if (err) warningMsg += '\n' + err.stack
+    console.warn(warningMsg)
   })
   asyncProvider.on('error', console.error.bind(console))
   self.asyncProvider = asyncProvider

app/scripts/lib/obj-multiplex.js

@@ -10,9 +10,9 @@ function ObjectMultiplex (opts) {
     var data = chunk.data
     var substream = mx.streams[name]
     if (!substream) {
-      console.warn('orphaned data for stream ' + name)
+      console.warn(`orphaned data for stream "${name}"`)
     } else {
-      substream.push(data)
+      if (substream.push) substream.push(data)
     }
     return cb()
   })
@@ -36,5 +36,9 @@ function ObjectMultiplex (opts) {
     }
     return substream
   }
+  // ignore streams (dont display orphaned data warning)
+  mx.ignoreStream = function (name) {
+    mx.streams[name] = true
+  }
   return mx
 }

app/scripts/lib/port-stream.js

@@ -53,8 +53,7 @@ PortDuplexStream.prototype._write = function (msg, encoding, cb) {
     }
     cb()
   } catch (err) {
-    console.error(err)
-    // this.emit('error', err)
+    // console.error(err)
     cb(new Error('PortDuplexStream - disconnected'))
   }
 }

package.json

@@ -59,6 +59,7 @@
     "mississippi": "^1.2.0",
     "multiplex": "^6.7.0",
     "once": "^1.3.3",
+    "ping-pong-stream": "^1.0.0",
     "pojo-migrator": "^2.1.0",
     "polyfill-crypto.getrandomvalues": "^1.0.0",
     "post-message-stream": "^1.0.0",