Added document max length limit, enforceMaxLength on change and show modal when reach the limit.

config.js

@@ -46,6 +46,7 @@ var config = {
     sessiontouch: 1 * 3600, //1 hour
     heartbeatinterval: 5000,
     heartbeattimeout: 10000,
+    documentmaxlength: 100000,
     //auth
     facebook: {
         clientID: 'change this',

lib/ot/editor-socketio-server.js

@@ -95,6 +95,7 @@ EditorSocketIOServer.prototype.onOperation = function (socket, revision, operati
     try {
         var clientId = socket.id;
         var wrappedPrime = this.receiveOperation(revision, wrapped);
+        if(!wrappedPrime) return;
         //console.log("new operation: " + JSON.stringify(wrapped));
         this.getClient(clientId).selection = wrappedPrime.meta;
         revision = this.operations.length;

lib/ot/server.js

@@ -1,3 +1,5 @@
+var config = require('../../config');
+
 if (typeof ot === 'undefined') {
   var ot = {};
 }
@@ -28,7 +30,10 @@ ot.Server = (function (global) {
     }
 
     // ... and apply that on the document.
-    this.document = operation.apply(this.document);
+    var newDocument = operation.apply(this.document);
+    // ignore if exceed the max length of document
+    if(newDocument.length > config.documentmaxlength) return;
+    this.document = newDocument;
     // Store operation in history.
     this.operations.push(operation);
 

lib/realtime.js

@@ -207,6 +207,7 @@ function emitRefresh(socket) {
     if (!notename || !notes[notename]) return;
     var note = notes[notename];
     socket.emit('refresh', {
+        docmaxlength: config.documentmaxlength,
         owner: note.owner,
         permission: note.permission,
         updatetime: note.updatetime
@@ -218,13 +219,12 @@ var connectionSocketQueue = [];
 var isDisconnectBusy = false;
 var disconnectSocketQueue = [];
 
-function finishConnection(socket, notename) {
-    var note = notes[notename];
-    note.users[socket.id] = users[socket.id];
+function finishConnection(socket, note, user) {
+    note.users[socket.id] = user;
     note.socks.push(socket);
     note.server.addClient(socket);
-    note.server.setName(socket, users[socket.id].name);
-    note.server.setColor(socket, users[socket.id].color);
+    note.server.setName(socket, user.name);
+    note.server.setColor(socket, user.color);
 
     emitOnlineUsers(socket);
     emitRefresh(socket);
@@ -240,8 +240,9 @@ function finishConnection(socket, notename) {
         startConnection(connectionSocketQueue[0]);
 
     if (config.debug) {
+        var notename = getNotenameFromSocket(socket);
         logger.info('SERVER connected a client to [' + notename + ']:');
-        logger.info(JSON.stringify(users[socket.id]));
+        logger.info(JSON.stringify(user));
         //logger.info(notes);
         getStatus(function (data) {
             logger.info(JSON.stringify(data));
@@ -293,11 +294,11 @@ function startConnection(socket) {
                     updatetime: moment(updatetime).valueOf(),
                     server: server
                 };
-                finishConnection(socket, notename);
+                finishConnection(socket, notes[notename], users[socket.id]);
             });
         });
     } else {
-        finishConnection(socket, notename);
+        finishConnection(socket, notes[notename], users[socket.id]);
     }
 }
 

public/js/index.js

@@ -909,10 +909,13 @@ socket.on('permission', function (data) {
     permission = data.permission;
     checkPermission();
 });
+var docmaxlength = null;
 var otk = null;
 var owner = null;
 var permission = null;
 socket.on('refresh', function (data) {
+    docmaxlength = data.docmaxlength;
+    editor.setOption("maxLength", docmaxlength);
     otk = data.otk;
     owner = data.owner;
     permission = data.permission;
@@ -1435,10 +1438,30 @@ function buildCursor(user) {
 }
 
 //editor actions
+function enforceMaxLength(cm, change) {
+    var maxLength = cm.getOption("maxLength");
+    if (maxLength && change.update) {
+        var str = change.text.join("\n");
+        var delta = str.length - (cm.indexFromPos(change.to) - cm.indexFromPos(change.from));
+        if (delta <= 0) {
+            return false;
+        }
+        delta = cm.getValue().length + delta - maxLength;
+        if (delta > 0) {
+            str = str.substr(0, str.length - delta);
+            change.update(change.from, change.to, str.split("\n"));
+            return true;
+        }
+    }
+    return false;
+}
 var ignoreEmitEvents = ['setValue', 'ignoreHistory'];
 editor.on('beforeChange', function (cm, change) {
     if (debug)
         console.debug(change);
+    if (enforceMaxLength(cm, change)) {
+        $('.limit-modal').modal('show');
+    }
     var isIgnoreEmitEvent = (ignoreEmitEvents.indexOf(change.origin) != -1);
     if (!isIgnoreEmitEvent) {
         switch (permission) {

public/views/body.ejs

@@ -110,4 +110,23 @@
             </div>
         </div>
     </div>
+</div>
+<!-- limit modal -->
+<div class="modal fade limit-modal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
+    <div class="modal-dialog modal-sm">
+        <div class="modal-content">
+            <div class="modal-header">
+                <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span>
+                </button>
+                <h4 class="modal-title" id="myModalLabel"><i class="fa fa-exclamation-triangle"></i> Reach the limit</h4>
+            </div>
+            <div class="modal-body" style="color:black;">
+                <h5>Sorry, you've reached the max length this note can be.</h5>
+                <strong>Please reduce the content or divided it to more notes, thank you!</strong>
+            </div>
+            <div class="modal-footer">
+                <button type="button" class="btn btn-warning" data-dismiss="modal">OK</button>
+            </div>
+        </div>
+    </div>
 </div>