Some browsers fail to load files from VFS (only Firefox works correctly)

[triuk]

I created a minimal example of some assets, I'd need in the future and observed that Brave, WebView, and Chromium fail to display the chart and custom slider, and parts of the UI do not function properly. Only Firefox loads everything as expected. The problem occurs on both Windows and Linux.

After checking the developer tools in Chromium, I found that several JavaScript files are not being loaded:

As shown above, files that are supposed to be inside the include directory are missing when running in Chromium-based browsers.

My C++ example project is available here:
https://gitlab.com/uklaad/example-webui-cpp

To reproduce the issue, simply modify the line 22 (show_browser) in src/app.cpp

For reference, the Python version of the same works without any issues across all tested browsers:
https://gitlab.com/uklaad/example-webui-python

[AlbertShown]

Thank you for the report and for the example code @triuk, I will investigate it soon.

[triuk]

Hi, I haven’t resolved the issue yet. I’ve reduced the code to a minimal example that shows only the problem, without any unrelated parts. The main.cpp simply opens the window, which is sufficient because the issue is most likely connected to the VFS. I also tried moving the JavaScript files to the root of the ui folder, but it didn’t help — they still don’t load.
You can find the minimal code below. The goal is simply to get "my ui" to load correctly in browsers other than Firefox. Files that do not load are: chart.umd.min.js ; chart.umd.min.js.map ; nouislider.min.js
example-webui-cpp-minimal.zip

[AlbertShown]

I started yester by cloning your repo and build project using cmake, then I got a compilation error, so I pause, was late night!
I will try this minimal one soon today.

[triuk]

Hi, I found a workaround = add defer at the script load.

<script src="include/nouislider.min.js" defer></script>
<script src="include/chart.umd.min.js" defer></script>
<script src="index.js" defer></script>

It seems more like monkey patch for me, as opening index.html directly from HDD with Chromium os OK, so I am not closing as solved yet. There may be differences how files are served in VFS in comparison with "casual" filesystem.

[AlbertShown]

I agree, it should work without the workaround. I will check this very soon today and let you know.

[triuk]

Well the defer is not stable solution anyway. Chromium loads OK most of the time with the defer (only once of ~20 attempts it did not load correctly - I do not like uncertainity :( ). But the WebView (Linux) is still doomed.

[AlbertShown]

[Core]          _webui_http_handler() -> GET [/include/chart.umd.min.js]
[Core]          _webui_get_cookies()
[Core]          _webui_http_handler() -> Client cookies []
[Core]          _webui_client_cookies_get_id()
[Core]          _webui_http_handler() -> Client ID not found
[Core]          _webui_http_handler() -> 403 Forbidden
[Core]          _webui_http_send_error()

The issue is that browser is calling chart.umd.min.js before webui.js, so WebUI refuse all HTTP requests by 403 Forbidden for security reason.

I don't think this is a bug, but WebUI should have a solution for this...

[AlbertShown]

The expected behavior is:

1. Browser request webui.js
2. WebUI set a secured cookies and tokens...
3. Browser request chart.umd.min.js with valid cookies and token, so WebUI answer with 200 OK

What happening right now:

1. Browser request chart.umd.min.js with empty cookies... WebUI refuse with 403 Forbidden
2. Browser request webui.js
3. WebUI set a secured cookies and tokens...
4. Browser request other files... WebUI answer with 200 OK

Thank you @triuk for reporting this, much appreciated.
We need to find a solution for this...

[AlbertShown]

webui::set_config(use_cookies, false); cause infinite loop in Debug mode cause printing .js content take too long... While it works fine in release mode.

[AlbertShown]

@triuk You can for now use webui::set_config(use_cookies, false);, it will work... while we still looking for a final fix to this scenario.