Merge pull request #1496 from MetaMask/reloadDapp

Reload the page when switching networks for sites that use web3

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## Current Master
 
+- Now when switching networks sites that use web3 will reload
 - Now when switching networks the extension does not restart
 - Cleanup decimal bugs in our gas inputs.
 - Fix bug where submit button was enabled for invalid gas inputs.

app/scripts/contentscript.js

@@ -61,7 +61,6 @@ function setupStreams () {
   // ignore unused channels (handled by background)
   mx.ignoreStream('provider')
   mx.ignoreStream('publicConfig')
-  mx.ignoreStream('reload')
 }
 
 function shouldInjectWeb3 () {

app/scripts/inpage.js

@@ -31,26 +31,11 @@ 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)
-
-// listen for reset requests from metamask
-var reloadStream = inpageProvider.multiStream.createStream('reload')
-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
-
-// disable pingStream until https://github.com/MetaMask/metamask-plugin/issues/746 is resolved more gracefully
-// metamaskStream.once('data', function(){
-//   pingStream.pipe(pingChannel).pipe(pingStream)
-// })
-// endOfStream(pingStream, triggerReload)
+// export global web3, with usage-detection
+setupDappAutoReload(web3, inpageProvider.publicConfigStore)
 
 // set web3 defaultAccount
+
 inpageProvider.publicConfigStore.subscribe(function (state) {
   web3.eth.defaultAccount = state.selectedAddress
 })

app/scripts/lib/auto-reload.js

@@ -1,30 +1,33 @@
-const once = require('once')
-const ensnare = require('ensnare')
-
 module.exports = setupDappAutoReload
 
-function setupDappAutoReload (web3) {
+function setupDappAutoReload (web3, observable) {
   // export web3 as a global, checking for usage
-  var pageIsUsingWeb3 = false
-  var resetWasRequested = false
-  global.web3 = ensnare(web3, once(function () {
-    // if web3 usage happened after a reset request, trigger reset late
-    if (resetWasRequested) return triggerReset()
-    // mark web3 as used
-    pageIsUsingWeb3 = true
-    // reset web3 reference
-    global.web3 = web3
-  }))
+  global.web3 = new Proxy(web3, {
+    get: (_web3, name) => {
+      // get the time of use
+      if (name !== '_used') _web3._used = Date.now()
+      return _web3[name]
+    },
+    set: (_web3, name, value) => {
+      _web3[name] = value
+    },
+  })
+  var networkVersion
 
-  return handleResetRequest
+  observable.subscribe(function (state) {
+    // get the initial network
+    const curentNetVersion = state.networkVersion
+    if (!networkVersion) networkVersion = curentNetVersion
 
-  function handleResetRequest () {
-    resetWasRequested = true
-    // ignore if web3 was not used
-    if (!pageIsUsingWeb3) return
-    // reload after short timeout
-    setTimeout(triggerReset, 500)
+    if (curentNetVersion !== networkVersion && web3._used) {
+      const timeSinceUse = Date.now() - web3._used
+      // if web3 was recently used then delay the reloading of the page
+      timeSinceUse > 500 ? triggerReset() : setTimeout(triggerReset, 500)
+      // prevent reentry into if statement if state updates again before
+      // reload
+      networkVersion = curentNetVersion
     }
+  })
 }
 
 // reload the page