aspnetcore: Update to SDK 2.2.100 throws "An item with the same key has already been added. Key: .wasm"

Thanks everyone for reporting this issue! I apologize for the inconvenience.

To workaround this issue you will need to have your Blazor projects continue to target .NET Core 2.1 (netcoreapp2.1). We aren’t planning to patch this issue because there is a workaround and we are currently focused on getting Razor Components into .NET Core 3.0. This issue will be fixed once we release the first public preview of Razor Components early next year.

@danroth27 So to summarize, there is currently no support for Blazor on .NET Core 2.2?

@danroth27 is there any chance to get a hotfix for this?

It looks like

“.wasm”, “application/wasm”

was recently added to FileExtensionContentTypeProvider: https://github.com/aspnet/AspNetCore/blob/master/src/StaticFiles/src/Microsoft.AspNetCore.StaticFiles/FileExtensionContentTypeProvider.cs (Commit: https://github.com/aspnet/StaticFiles/commit/a5fcd9dd8724eb71f0642340f68aeb85b0473374#diff-3534185c350428a9c533fe5c29596890)

The UseBlazor method calls CreateContentTypeProvider which will always fail as a result of the .wasm addition:

private static IContentTypeProvider CreateContentTypeProvider(bool enableDebugging)
    {
      FileExtensionContentTypeProvider contentTypeProvider = new FileExtensionContentTypeProvider();
      contentTypeProvider.Mappings.Add(".dll", "application/octet-stream");
      contentTypeProvider.Mappings.Add(".mem", "application/octet-stream");
      contentTypeProvider.Mappings.Add(".wasm", "application/wasm");
      if (enableDebugging)
        contentTypeProvider.Mappings.Add(".pdb", "application/octet-stream");
      return (IContentTypeProvider) contentTypeProvider;
    } 

Update: The issue has been addressed as part of this commit: https://github.com/aspnet/AspNetCore/commit/5c1fbe1af7b8b6a36289de0d175608a16a1e284c#diff-0cff27aae9e3ba66997ab8244a54fa57

@danroth27 So to summarize, there is currently no support for Blazor on .NET Core 2.2?

@isaac2004 That’s correct. And instead of spending time patching it we are focusing our efforts on getting Razor Components working in .NET Core 3.0.

I got the exactly same issue this morning. Rolling back to 2.1 framework is fine.

My workaround is simpler. Just use this global.json. Done.

{
  "sdk": {
    "version": "2.2.100-preview3-009430"
  }
}

And you need of course the corresponding SDK installed 😸 Even my updates mentioned earlier work fine.

@sheryever Could you please open a new issue with the full details on how to reproduce the problem you are seeing?

@ctrl-alt-d Looks like your app must still be using the earlier packages (Blazor 0.7.0?). It’s only fixed in the newer bits we haven’t released yet.

John,

You’re right. I missed the change to CreateContentTypeProvider() as I read through the change set.

Best regards,

Metro.

Sent from my iPad

On Dec 12, 2018, at 5:56 PM, John Cornell <notifications@github.commailto:notifications@github.com> wrote:

@msauperhttps://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fmsauper&data=02|01||eab718084024429c8ceb08d660850427|84df9e7fe9f640afb435aaaaaaaaaaaa|1|0|636802521742252794&sdata=iKxrlbXdEk%2BL%2B0QhD4wP6f%2F6R4%2FUo3opi5ugsxRiR%2FA%3D&reserved=0 In the commit that I linked to: aspnet/AspNetCore@5c1fbe1#diff-0cff27aae9e3ba66997ab8244a54fa57https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Faspnet%2FAspNetCore%2Fcommit%2F5c1fbe1af7b8b6a36289de0d175608a16a1e284c%23diff-0cff27aae9e3ba66997ab8244a54fa57&data=02|01||eab718084024429c8ceb08d660850427|84df9e7fe9f640afb435aaaaaaaaaaaa|1|0|636802521742252794&sdata=gCBzuKDR3mJYxTBO105huB%2Fo%2B7fS9wb%2FZ2fVtzR0o2c%3D&reserved=0 the Additions are using the same AddMapping() logic:

private static IContentTypeProvider CreateContentTypeProvider(bool enableDebugging) { var result = new FileExtensionContentTypeProvider(); AddMapping(result, “.dll”, MediaTypeNames.Application.Octet); AddMapping(result, “.wasm”, WasmMediaTypeNames.Application.Wasm);

    if (enableDebugging)
    {
            AddMapping(result, ".pdb", MediaTypeNames.Application.Octet);
    }

    return result;

}

private static void AddMapping(FileExtensionContentTypeProvider provider, string name, string mimeType) { if (!provider.Mappings.ContainsKey(name)) { provider.Mappings.Add(name, mimeType); } }

Or am I misunderstanding what you’re saying?

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHubhttps://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Faspnet%2FBlazor%2Fissues%2F1750%23issuecomment-446775578&data=02|01||eab718084024429c8ceb08d660850427|84df9e7fe9f640afb435aaaaaaaaaaaa|1|0|636802521742252794&sdata=OQ5xuVjNUfbwIpgS719ciq%2BToVkXJOokxAsrW%2BiXkO4%3D&reserved=0, or mute the threadhttps://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fnotifications%2Funsubscribe-auth%2FADottvAYL8GcZU8KK0-HhyDo2V9GhJaOks5u4YmMgaJpZM4ZCVjx&data=02|01||eab718084024429c8ceb08d660850427|84df9e7fe9f640afb435aaaaaaaaaaaa|1|0|636802521742252794&sdata=pp3L2EbjaKa3lu5MG%2FsLKHKK8yBqEXdZj801NQuBCGY%3D&reserved=0.

@michaelvolz interesting stuff … based on this global.json is no more and it’s replaced by *.csproj Opening mine yielded some interesting stuff - I was using 2.1.500 (no matter that I choose .NET Core 2.2 upon solution creation - using Visual Studio 2017 community) and when changed to 2.2 - it did gives me error on windows too with the same exception. Will update to latest preview to see if it’s working on linux. Thanks for pointing me to the right direction.