Replace unreliable onBeforeUnload with tabs.onRemoved

README.md

@@ -3,7 +3,7 @@ Simple Google Meet transcripts. Private and open source.
 
 ![marquee-large](/assets/marquee-large.png)
 
-Extension status: 🟢 OPERATIONAL (v2.1.2)
+Extension status: 🟢 OPERATIONAL (v2.1.3)
 
 <br />
 <br />

extension/background.js

@@ -1,26 +1,38 @@
 chrome.runtime.onMessage.addListener(function (message, sender, sendResponse) {
     console.log(message.type)
-    if (message.type == "save_and_download") {
-        chrome.storage.local.set(
-            {
-                transcript: message.transcript,
-                chatMessages: message.chatMessages,
-                meetingTitle: message.meetingTitle,
-                meetingStartTimeStamp: message.meetingStartTimeStamp
-            },
-            function () {
-                console.log("Saved transcript and meta data, downloading now if non empty")
-                // Download only if any transcript is present, irrespective of chat messages
-                if (message.transcript.length > 0)
-                    downloadTranscript()
+    if (message.type == "new_meeting_started") {
+        // Saving current tab id, to download transcript when this tab is closed
+        chrome.tabs.query({ active: true, currentWindow: true }, function (tabs) {
+            const tabId = tabs[0].id
+            chrome.storage.local.set({ meetingTabId: tabId }, function () {
+                console.log("Meeting tab id saved")
             })
+        })
     }
     if (message.type == "download") {
+        // Invalidate tab id since transcript is downloaded, prevents double downloading of transcript from tab closed event listener
+        chrome.storage.local.set({ meetingTabId: null }, function () {
+            console.log("Meeting tab id cleared")
+        })
         downloadTranscript()
     }
     return true
 })
 
+// Download transcript if meeting tab is closed
+chrome.tabs.onRemoved.addListener(function (tabid) {
+    chrome.storage.local.get(["meetingTabId"], function (data) {
+        if (tabid == data.meetingTabId) {
+            console.log("Successfully intercepted tab close")
+            downloadTranscript()
+            // Clearing meetingTabId to prevent misfires of onRemoved until next meeting actually starts
+            chrome.storage.local.set({ meetingTabId: null }, function () {
+                console.log("Meeting tab id cleared for next meeting")
+            })
+        }
+    })
+})
+
 function downloadTranscript() {
     chrome.storage.local.get(["userName", "transcript", "chatMessages", "meetingTitle", "meetingStartTimeStamp"], function (result) {
         if (result.userName && result.transcript && result.chatMessages) {

extension/content.js

@@ -67,6 +67,9 @@ checkExtensionStatus().then(() => {
       // CRITICAL DOM DEPENDENCY. Wait until the meeting end icon appears, used to detect meeting start
       checkElement(".google-material-icons", "call_end").then(() => {
         console.log("Meeting started")
+        chrome.runtime.sendMessage({ type: "new_meeting_started" }, function (response) {
+          console.log(response);
+        });
         hasMeetingStarted = true
 
         try {
@@ -134,19 +137,14 @@ checkExtensionStatus().then(() => {
 
 
           //*********** MEETING END ROUTINES **********//
-          // Event listener to capture browser tab or window close
-          window.addEventListener("beforeunload", unloadCallback)
-
           // CRITICAL DOM DEPENDENCY. Event listener to capture meeting end button click by user
           contains(".google-material-icons", "call_end")[0].parentElement.addEventListener("click", () => {
             // To suppress further errors
             hasMeetingEnded = true
-            // Remove unload event listener registered earlier, to prevent double downloads. Otherwise, unload event will trigger the callback, when user navigates away from meeting end page.
-            window.removeEventListener("beforeunload", unloadCallback)
             transcriptObserver.disconnect()
             chatMessagesObserver.disconnect()
 
-            // Push any data in the buffer variables to the transcript array, but avoid pushing blank ones. Handles one or more speaking when meeting ends.
+            // Push any data in the buffer variables to the transcript array, but avoid pushing blank ones. Needed to handle one or more speaking when meeting ends.
             if ((personNameBuffer != "") && (transcriptTextBuffer != ""))
               pushBufferToTranscript()
             // Save to chrome storage and send message to download transcript from background script
@@ -272,27 +270,6 @@ const commonCSS = `background: rgb(255 255 255 / 10%);
     font-family: 'Google Sans',Roboto,Arial,sans-serif; 
     box-shadow: rgba(0, 0, 0, 0.16) 0px 10px 36px 0px, rgba(0, 0, 0, 0.06) 0px 0px 0px 1px;`;
 
-// Pushes any data in the buffer to transcript and tells background script to save it and download it
-function unloadCallback() {
-  // To suppress further errors
-  hasMeetingEnded = true
-  // Push any data in the buffer variables to the transcript array, but avoid pushing blank ones. Handles one or more speaking when meeting ends.
-  if ((personNameBuffer != "") && (transcriptTextBuffer != ""))
-    pushBufferToTranscript()
-  // Send a message to save to chrome storage as well as download. Saving is offloaded to background script, since browser often aborts this long operation on unload
-  chrome.runtime.sendMessage(
-    {
-      type: "save_and_download",
-      transcript: transcript,
-      chatMessages: chatMessages,
-      meetingTitle: meetingTitle,
-      meetingStartTimeStamp: meetingStartTimeStamp,
-    },
-    function (response) {
-      console.log(response)
-    })
-}
-
 // Callback function to execute when transcription mutations are observed. 
 function transcriber(mutationsList, observer) {
   // Delay for 1000ms to allow for text corrections by Meet.