From a4786c96898de09cb6174f4abe6b7d19009d1cb6 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Wed, 23 Dec 2020 11:39:54 +0100
Subject: [PATCH] [Scripting] Await manually triggered `dispatchEventInSandbox`
calls in the viewer
Given that the `dispatchEventInSandbox` method (on the scripting-classes) is asynchronous, there's a very real risk that the events won't be dispatched/handled until *after* their associated functionality has actually run (with the "Will..." events being particularily susceptible to this issue).
To reduce the likelihood of that happening, we can simply `await` the `dispatchEventInSandbox` calls as necessary. A couple of methods are now marked as `async` to support these changes, however that shouldn't be a problem as far as I can tell.
*Please note:* Given that the browser "beforeprint"/"afterprint" events are *synchronous*, we unfortunately cannot await the `WillPrint`/`DidPrint` event dispatching. To fix this properly the web-platform would need support for asynchronous printing, and we'll thus have to hope that things work correctly anyway.
---
web/app.js | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/web/app.js b/web/app.js
index 6040dc854..21266514b 100644
--- a/web/app.js
+++ b/web/app.js
@@ -1013,7 +1013,7 @@ const PDFViewerApplication = {
.catch(downloadByUrl); // Error occurred, try downloading with the URL.
},
- save({ sourceEventType = "download" } = {}) {
+ async save({ sourceEventType = "download" } = {}) {
if (this._saveInProgress) {
return;
}
@@ -1036,12 +1036,13 @@ const PDFViewerApplication = {
this.download({ sourceEventType });
return;
}
- this._scriptingInstance?.scripting.dispatchEventInSandbox({
+ this._saveInProgress = true;
+
+ await this._scriptingInstance?.scripting.dispatchEventInSandbox({
id: "doc",
name: "WillSave",
});
- this._saveInProgress = true;
this.pdfDocument
.saveDocument(this.pdfDocument.annotationStorage)
.then(data => {
@@ -1051,8 +1052,8 @@ const PDFViewerApplication = {
.catch(() => {
this.download({ sourceEventType });
})
- .finally(() => {
- this._scriptingInstance?.scripting.dispatchEventInSandbox({
+ .finally(async () => {
+ await this._scriptingInstance?.scripting.dispatchEventInSandbox({
id: "doc",
name: "DidSave",
});
@@ -1614,7 +1615,7 @@ const PDFViewerApplication = {
return;
}
- scripting.dispatchEventInSandbox({
+ await scripting.dispatchEventInSandbox({
id: "doc",
name: "Open",
});
@@ -1967,6 +1968,8 @@ const PDFViewerApplication = {
},
beforePrint() {
+ // Given that the "beforeprint" browser event is synchronous, we
+ // unfortunately cannot await the scripting event dispatching here.
this._scriptingInstance?.scripting.dispatchEventInSandbox({
id: "doc",
name: "WillPrint",
@@ -2033,6 +2036,8 @@ const PDFViewerApplication = {
},
afterPrint() {
+ // Given that the "afterprint" browser event is synchronous, we
+ // unfortunately cannot await the scripting event dispatching here.
this._scriptingInstance?.scripting.dispatchEventInSandbox({
id: "doc",
name: "DidPrint",