Firefox timeout/disconnect fix over localhost with reloads from memory cache

client/index.js

@@ -5,21 +5,42 @@ var on = require('sendevent')
 
 var token
 
+function reloadPage() {
+  // Firefox has a quirk where it times out and disconnects an EventSource
+  // connection when the host (not hostname) is “localhost” and it does
+  // a regular reload from memory cache. Instead, we must do a forced reload from
+  // the server and also flag it so that sendevent doesn’t also do
+  // a forced reload just to be sure (and thereby adding an unnecessary reload).
+  // Also, when we do a forced reload, Firefox loses the current scroll position
+  // so we must save that so checking for the existence of the object that contains
+  // the location to restore is how we know that we have asked for a force reload.
+  if (navigator.userAgent.includes('Firefox') && document.location.host === 'localhost') {
+    window.locationToRestoreAfterForcedReload = {
+      x: window.scrollX,
+      y: window.scrollY
+    }
+    location.reload(true)
+  } else {
+    // In every other case, we can just do a regular reload.
+    location.reload()
+  }
+}
+
 on('/instant/events', function(ev) {
   if (ev.token) {
     if (!token) token = ev.token
-    if (token != ev.token) return location.reload()
+    if (token != ev.token) return reloadPage()
   }
 
   // reload page if it contains an element with the given class name
   if (ev.className) {
-    if (find.byClass(ev.className)) location.reload()
+    if (find.byClass(ev.className)) reloadPage()
     return
   }
 
   // reload page if it contains an element that matches the given selector
   if (ev.selector) {
-    if (find.bySelector(ev.selector)) location.reload()
+    if (find.bySelector(ev.selector)) reloadPage()
     return
   }
 
@@ -28,7 +49,7 @@ on('/instant/events', function(ev) {
 
   // reload the page
   if (url.href == location.href) {
-    location.reload()
+    reloadPage()
     return
   }
 
@@ -38,5 +59,5 @@ on('/instant/events', function(ev) {
 
   // look for a script
   el = find.byURL('script', 'src', url)
-  if (el) location.reload()
+  if (el) reloadPage()
 })

package.json

@@ -27,7 +27,7 @@
     "filewatcher": "^3.0.1",
     "node-graceful": "^2.0.1",
     "send": "^0.17.1",
-    "sendevent": "^1.0.4",
+    "sendevent": "^1.0.6",
     "stacked": "^1.1.1",
     "tamper": "^0.1.0"
   },