logging JS errors to backend logs

public/javascripts/context_menu.js

@@ -121,7 +121,7 @@ const contextMenu = (function() {
                 treeChanges.deleteNode(node);
             }
             else {
-                console.log("Unknown command: " + ui.cmd);
+                messaging.logError("Unknown command: " + ui.cmd);
             }
         }
     };

public/javascripts/dialogs/jump_to_note.js

@@ -80,7 +80,7 @@ const jumpToNote = (function() {
             dialogEl.dialog("close");
         }
         else {
-            console.error("Unknown action=" + action);
+            messaging.logError("Unknown action=" + action);
         }
 
         return false;

public/javascripts/init.js

@@ -126,3 +126,26 @@ function showAppIfHidden() {
         loaderDiv.style.opacity = 0.0;
     }
 }
+
+window.onerror = function (msg, url, lineNo, columnNo, error) {
+    const string = msg.toLowerCase();
+
+    let message = "Uncaught error: ";
+
+    if (string.indexOf("script error") > -1){
+        message += 'No details available';
+    }
+    else {
+        message += [
+            'Message: ' + msg,
+            'URL: ' + url,
+            'Line: ' + lineNo,
+            'Column: ' + columnNo,
+            'Error object: ' + JSON.stringify(error)
+        ].join(' - ');
+    }
+
+    messaging.logError(message);
+
+    return false;
+};

public/javascripts/messaging.js

@@ -1,9 +1,20 @@
 "use strict";
 
 const messaging = (function() {
-    function messageHandler(event) {
+    let ws = null;
-        console.log(event.data);
 
+    function logError(message) {
+        console.error(message);
+
+        if (ws && ws.readyState === 1) {
+            ws.send(JSON.stringify({
+                type: 'log-error',
+                error: message
+            }));
+        }
+    }
+
+    function messageHandler(event) {
         const message = JSON.parse(event.data);
 
         if (message.type === 'sync') {
@@ -27,8 +38,6 @@ const messaging = (function() {
         }
     }
 
-    let ws = null;
-
     function connectWebSocket() {
         // use wss for secure messaging
         ws = new WebSocket("ws://" + location.host);
@@ -65,4 +74,8 @@ const messaging = (function() {
             showMessage("Re-connected to server");
         }
     }, 3000);
+
+    return {
+        logError
+    };
 })();

public/javascripts/note_tree.js

@@ -144,7 +144,7 @@ const noteTree = (function() {
     function prepareNoteTreeInner(parentNoteId) {
         const childNoteIds = parentToChildren[parentNoteId];
         if (!childNoteIds) {
-            console.log("No children for " + parentNoteId + ". This shouldn't happen.");
+            messaging.logError("No children for " + parentNoteId + ". This shouldn't happen.");
             return;
         }
 
@@ -201,7 +201,7 @@ const noteTree = (function() {
                 const parents = childToParents[childNoteId];
 
                 if (!parents) {
-                    console.error("No parents found for " + childNoteId);
+                    messaging.logError("No parents found for " + childNoteId);
                     return;
                 }
 
@@ -218,7 +218,7 @@ const noteTree = (function() {
                         break;
                     }
                     else {
-                        console.log("No parents, can't activate node.");
+                        messaging.logError("No parents, can't activate node.");
                         return;
                     }
                 }

services/messaging.js

@@ -20,8 +20,20 @@ function init(httpServer, sessionParser) {
         server: httpServer
     });
 
-    webSocketServer.on('connection', function connection(ws, req) {
+    webSocketServer.on('connection', (ws, req) => {
         console.log("websocket client connected");
+
+        ws.on('message', messageJson => {
+            const message = JSON.parse(messageJson);
+
+            if (message.type === 'log-error') {
+                log.error('JS Error: ' + message.error);
+            }
+            else {
+                log.error('Unrecognized message: ');
+                log.error(message);
+            }
+        });
     });
 }