Hosted Blazor Web App throws error when opening (invalid cache?)

[Code-Chops]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

When opening our hosted Blazor app our customers get an exception.

Clearing the cache fixes the problem. I think this problem occurs because the old DLLs are still in the cache storage. What is the problem here? And what can I do about it? At the moment we have to tell our customers to clear the cache in the developer window, which is unwanted of course. Thanks in advance!

Expected Behavior

A working Blazor Web App

Steps To Reproduce

No response

Exceptions (if any)

dotnet.runtime.8.0.2.xpxg2k6ml2.js:3 MONO_WASM: instantiate_wasm_module() failed LinkError: WebAssembly.instantiate(): Import #42 module="env" function="dlopen": function import requires a callable
dt @ dotnet.runtime.8.0.2.xpxg2k6ml2.js:3
dotnet.js:3 MONO_WASM: LinkError: WebAssembly.instantiate(): Import #42 module="env" function="dlopen": function import requires a callable
u @ dotnet.js:3
blazor.web.js?v=2.3.16:1 Error in mono_download_assets: LinkError: WebAssembly.instantiate(): Import #42 module="env" function="dlopen": function import requires a callable
Rr @ blazor.web.js?v=2.3.16:1
4dotnet.js:3 Uncaught (in promise) LinkError: WebAssembly.instantiate(): Import #42 module="env" function="dlopen": function import requires a callable
dotnet.runtime.8.0.2.xpxg2k6ml2.js:3 Uncaught (in promise) LinkError: WebAssembly.instantiate(): Import #42 module="env" function="dlopen": function import requires a callable
2app.dentalrules.nl/:1 Uncaught (in promise) LinkError: WebAssembly.instantiate(): Import #42 module="env" function="dlopen": function import requires a callable
blazor.web.js?v=2.3.16:1 Uncaught (in promise) Error: Failed to start platform. Reason: LinkError: WebAssembly.instantiate(): Import #42 module="env" function="dlopen": function import requires a callable
at ei (blazor.web.js?v=2.3.16:1:164030)
blazor.web.js?v=2.3.16:1 Uncaught (in promise) LinkError: WebAssembly.instantiate(): Import #42 module="env" function="dlopen": function import requires a callable

.NET Version

8.0.201

Anything else?

No response

[javiercn]

@Code-Chops thanks for contacting us.

You can use Clear-Site-Data to wipe out existing storage for the app, or add a small script to the page before Blazor loads to clear the cache manually if you are running into issues.

[Code-Chops]

Thank you very much! Do you know why this is happening? Shouldn't Blazor check if newer versions are available and clear the cache accordingly?

[Code-Chops]

And what cache are we talking about? Because we clear the 'Cache storage' and the problem still exists

[MackinnonBuck]

Thanks for reaching out. Just a few questions:

1. Does your app use a service worker?
2. Could you provide us with information about your deployment environment?
3. Does the issue occur even when loading the page in a private browser window?

If possible, please also provide us with a minimal repro project hosted as a public GitHub repository so we can look into this issue further. Thanks!

And what cache are we talking about? Because we clear the 'Cache storage' and the problem still exists

There is a hash in blazor.boot.json that Blazor uses to determine whether the assets have changed and need to be re-downloaded.

[Code-Chops]

Sorry for the late response. We finally got it working by adding an ETag in our headers with the current version of the application as value. But now we get the following warning in the console:
dotnet.runtime.8.0.3.b85ar3xvhg.js:3 MONO_WASM: The version of dotnet.native.js is different from the version of dotnet.js!

Can we ignore this error?

@MackinnonBuck

1. Our app does not include a service worker
2. We deploy in Kubernetes using Azure DevOps.
3. The error also occurs in an incognito window.

It was difficult for me to recreate a repro.

Thank you!

[bytefish]

@Code-Chops I get this error aswell:

logging.ts:26  MONO_WASM: The version of dotnet.native.js is different from the version of dotnet.js!

And I am wondering, if this error can be ignored or not.

I've just updated to .NET 8 and deleted the obj / bin folders, cleared all site data, and restarted Visual Studio to no success.

[omni-htg]

During the upgrade to 8.0.10 from 8.0.8 experiencing the same issues as @bytefish above.
Reported a new issue #58313 for it.