LabVIEW NXG: Why cannot my WebVI be loaded successfully everytime?

[richtian]

Hi,

I'm using NXG 4.0 to build a WebVI for my application to publish some data. However, when I'm connecting to the WebVI using Firefox (version 68+), I'm running into situations where the WebVI randomly fails to be loaded. I'm getting an error "Unable to load required dependencies. Please verify all WebVI files are available and served using an http server or use a browser that can load files directly from the filesystem." in the browser. If I use Chrome, it seems that I rarely run into such an error. I'm wondering anybody can help me on this. Give me any hints on what to investigate.

Thanks,

Richie

[Tepig]

Hi richtian, I think my previous post would be helpful.

Solved: What are browser requirements to run web application developed with NXG Web Module - NI Comm...

MilanR said,

The WebVI has to be hosted on a Web Server for some browsers to run it.

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[richtian]

Hi, Emboar,

Thanks for your quick reply.

I do publish the built out HTML/CSS/... in an RT target with Web Server on it. I access the webpage in the browser by an address like : http://192.168.1.100:8002/index.html. Since it's not an always failure, I suspect that there could be something ignored.

BTW, by adding some debug codes, I find that the browser does not request the index.via.txt when I get the error. When the page is loaded successfully, the browser requests both index.via.txt and wasm file.

Thanks,

Richie

[MilanR]

Hi Richie,

There is a known issue with the latest version of Firefox (74) that was mentioned in the following thread: https://forums.ni.com/t5/LabVIEW/WebVI-Issues-with-Firefox-Update/m-p/4028515/highlight/true#M115461...

Quoted as follows:

Unfortunately, there is a WebVI incompatibility with the latest version of Firefox. R&D has investigated the issue and it is a problem on the WebVI side. There's no known end-user workaround.

Until NI provides a patch or a new version of NXG with the fix, we recommend that you use other browsers.

I apologize for the inconvenience!

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[richtian]

Hi，

This does not seem to be my problem. Today, I add a simple JSLI into my project. I find that I'm running into such failure much more frequently. It seems to me that the browser has trouble to always load every dependency successfully. I'm not an HTML person. I'm expecting to get the right direction for using NXG Web Module.

Thanks,

Richie

[MilanR]

Hi Richie,

Can you open the Firefox Web Console to see if there are any errors that are being logged by the WebVI or by the browser. The logs from a page that fails to load may give some insight on the cause of the failure.

Firefox appears to have the topic Opening the Web Console with instructions for opening the console and the Web Console topic gives a short video introducing the Firefox Web Console. Other browsers offer a similar set of tools such as the Chrome DevTools console.