From f93e294fff65f15b68faf2f2dcaea9893fb22cc0 Mon Sep 17 00:00:00 2001
From: Nicolas Bayet <nby@odoo.com>
Date: Thu, 2 Mar 2023 14:50:25 +0000
Subject: [PATCH] [FIX] web_editor: prevent corruption from stale document

When a peer "A" connect to the peer to peer network, if he receive a
stale document from a peer "B", peer "A" will never be able to save.
This situation can make impossible for any new peer to receive a
converging document and block the ability to save until every peer
disconnect from the network.

task-3196778

closes odoo/odoo#114268

X-original-commit: 537f34f764fae3967496d466c420d72d172b241d
Signed-off-by: David Monjoie (dmo) <dmo@odoo.com>
---
 .../static/src/js/wysiwyg/wysiwyg.js          | 67 +++++++------------
 1 file changed, 26 insertions(+), 41 deletions(-)

diff --git a/addons/web_editor/static/src/js/wysiwyg/wysiwyg.js b/addons/web_editor/static/src/js/wysiwyg/wysiwyg.js
index ad148ca5407..a969d2da19b 100644
--- a/addons/web_editor/static/src/js/wysiwyg/wysiwyg.js
+++ b/addons/web_editor/static/src/js/wysiwyg/wysiwyg.js
@@ -519,7 +519,8 @@ const Wysiwyg = Widget.extend({
                             break;
                         case 'rtc_data_channel_open': {
                             fromClientId = notificationPayload.connectionClientId;
-                            this.ptp.clientsInfos[fromClientId].startTime = await this.ptp.requestClient(fromClientId, 'get_start_time', undefined, { transport: 'rtc' });
+                            const remoteStartTime = await this.ptp.requestClient(fromClientId, 'get_start_time', undefined, { transport: 'rtc' });
+                            this.ptp.clientsInfos[fromClientId].startTime = remoteStartTime;
                             this.ptp.requestClient(fromClientId, 'get_client_name', undefined, { transport: 'rtc' }).then((clientName) => {
                                 this.ptp.clientsInfos[fromClientId].clientName = clientName;
                             });
@@ -528,8 +529,30 @@ const Wysiwyg = Widget.extend({
                             });
 
                             if (!historySyncAtLeastOnce) {
-                                historySyncAtLeastOnce = true;
-                                await editorCollaborationOptions.onHistoryNeedSync();
+                                const localClient = { id: this._currentClientId, startTime: this._startCollaborationTime };
+                                const remoteClient = { id: fromClientId, startTime: remoteStartTime };
+                                if (isClientFirst(localClient, remoteClient)) {
+                                    historySyncAtLeastOnce = true;
+                                } else {
+                                    const { steps, historyIds } = await this.ptp.requestClient(fromClientId, 'get_history_from_snapshot', undefined, { transport: 'rtc' });
+                                    // Ensure that the history hasn't been
+                                    // synced by another client before this
+                                    // `get_history_from_snapshot` finished.
+                                    if (historySyncAtLeastOnce) {
+                                        return;
+                                    }
+                                    const firstStepId = this.odooEditor.historyGetBranchIds()[0];
+                                    const staleDocument = !historyIds.includes(firstStepId);
+                                    if (staleDocument) {
+                                        return false;
+                                    }
+                                    historySyncAtLeastOnce = true;
+                                    this.odooEditor.historyResetFromSteps(steps, historyIds);
+                                    const remoteSelection = await this.ptp.requestClient(fromClientId, 'get_collaborative_selection', undefined, { transport: 'rtc' });
+                                    if (remoteSelection) {
+                                        this.odooEditor.onExternalMultiselectionUpdate(remoteSelection);
+                                    }
+                                }
                                 historySyncFinished = true;
                             } else {
                                 const remoteSelection = await this.ptp.requestClient(fromClientId, 'get_collaborative_selection', undefined, { transport: 'rtc' });
@@ -646,44 +669,6 @@ const Wysiwyg = Widget.extend({
                 }
                 this.ptp && this.odooEditor.onExternalHistorySteps(missingSteps.concat([step]));
             },
-            onHistoryNeedSync: async () => {
-                if (!this.ptp) return;
-                let firstClientId = this._currentClientId;
-                let firstClientStartTime = this._startCollaborationTime;
-                const connectedClientIds = this.ptp.getConnectedClientIds();
-                for (const clientId of connectedClientIds) {
-                    const clientInfo = this.ptp.clientsInfos[clientId];
-                    // Ensure we already retreived remote client starting time.
-                    if (!clientInfo.startTime) {
-                        continue;
-                    }
-
-                    const isCurrentClientFirst = isClientFirst(
-                        {
-                            startTime: clientInfo.startTime,
-                            id: clientId,
-                        },
-                        {
-                            startTime: firstClientStartTime,
-                            id: firstClientId,
-                        }
-                    );
-
-                    if (isCurrentClientFirst) {
-                        firstClientStartTime = clientInfo.startTime;
-                        firstClientId = clientId;
-                    }
-                }
-
-                if (firstClientId !== this._currentClientId) {
-                    const { steps, historyIds } = await this.ptp.requestClient(firstClientId, 'get_history_from_snapshot', undefined, { transport: 'rtc' });
-                    this.odooEditor.historyResetFromSteps(steps, historyIds);
-                    const remoteSelection = await this.ptp.requestClient(firstClientId, 'get_collaborative_selection', undefined, { transport: 'rtc' });
-                    if (remoteSelection) {
-                        this.odooEditor.onExternalMultiselectionUpdate(remoteSelection);
-                    }
-                }
-            },
         };
         return editorCollaborationOptions;
     },