`wasm-tools` workload breaks `dotnet publish` on Alpine Linux .NET SDK container image

[tibuprophen]

Describe the bug

I am developing a Blazor WASM Application. I want to use the .NET 6 introduced Native Build for Sqlite (A nice package is delivered by this nice guy: https://github.com/JeremyLikness/SqliteWasmHelper).

To activate the Native Build Feature I need to install wasm-tools workload.

Developing on my Host machine works fine, but when I try to dockerize this, it comes to errors, especially setting the configuration as dotnet publish parameter in combination with installing the WASM-Tools:
✅ Not installing WASM Tools is working
✅ Installing WASM Tools without dotnet publish parameters is working
🚫 Installing WASM Tools and using dotnet publish parameters is not working

Please see my examples to reproduce for further details.

To Reproduce

✅ Not installing WASM Tools is working

FROM mcr.microsoft.com/dotnet/sdk:7.0-alpine

#RUN dotnet workload install wasm-tools
WORKDIR /app

RUN dotnet new blazorwasm -o BlazorEmpty
WORKDIR /app/BlazorEmpty
#RUN dotnet publish
RUN dotnet publish --configuration Release

✅ Installing WASM Tools without dotnet publish parameters is working

FROM mcr.microsoft.com/dotnet/sdk:7.0-alpine

RUN dotnet workload install wasm-tools
WORKDIR /app

RUN dotnet new blazorwasm -o BlazorEmpty
WORKDIR /app/BlazorEmpty
RUN dotnet publish
# RUN dotnet publish --configuration Release

🚫 Installing WASM Tools and using dotnet publish parameters is not working

FROM mcr.microsoft.com/dotnet/sdk:7.0-alpine

RUN dotnet workload install wasm-tools
WORKDIR /app

RUN dotnet new blazorwasm -o BlazorEmpty
WORKDIR /app/BlazorEmpty
# RUN dotnet publish
RUN dotnet publish --configuration Release

The last scenario should work imo. I get the following error:

 > [6/6] RUN dotnet publish --configuration Release:                                                                                                                                                                                                                
#0 0.551 MSBuild version 17.5.1+f6fdcf537 for .NET                                                                                                                                                                                                                  
#0 1.972   Determining projects to restore...                                                                                                                                                                                                                       
#0 3.204   All projects are up-to-date for restore.                                                                                                                                                                                                                 
#0 8.343   BlazorEmpty -> /app/BlazorEmpty/bin/Release/net7.0/BlazorEmpty.dll                                                                                                                                                                                       
#0 8.345   BlazorEmpty (Blazor output) -> /app/BlazorEmpty/bin/Release/net7.0/wwwroot
#0 8.526   Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
#0 8.531   Optimizing assemblies for size. This process might take a while.
#0 12.77   Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
#0 12.80   /bin/sh: /tmp/MSBuildTemproot/tmp2b43989dc6514e5c8ed88e234186b25d.exec.cmd: line 2: /usr/share/dotnet/packs/Microsoft.NETCore.App.Runtime.AOT.linux-x64.Cross.browser-wasm/7.0.5/Sdk/../tools/mono-aot-cross: not found
#0 12.80 /usr/share/dotnet/packs/Microsoft.NET.Runtime.WebAssembly.Sdk/7.0.5/Sdk/WasmApp.Native.targets(283,5): error MSB3073: The command ""/usr/share/dotnet/packs/Microsoft.NETCore.App.Runtime.AOT.linux-x64.Cross.browser-wasm/7.0.5/Sdk/../tools/mono-aot-cross" --print-icall-table > "/app/BlazorEmpty/obj/Release/net7.0/wasm/for-publish/runtime-icall-table.h"" exited with code 127. [/app/BlazorEmpty/BlazorEmpty.csproj]

It tells me mono-aot-cross: not found is not found and docker exited with code 127 (file in container not found), but the file is available.

Further technical details

• Please let me know if you need any further technical details.
• I've tested this on Docker for MacOS and Linux (Ubuntu)

[tibuprophen]

Update / Workaround

By not using alpine and installing python3 seems to fix the problem. Dockerfile looks like this:

FROM mcr.microsoft.com/dotnet/sdk:7.0

RUN dotnet workload install wasm-tools
WORKDIR /app

RUN dotnet new blazorwasm -o BlazorEmpty
WORKDIR /app/BlazorEmpty

RUN apt-get update
RUN apt-get install -y python3

RUN dotnet publish --configuration Release

[baronfel]

I repro (thanks for the Dockerfiles!) and I think part of the scenario might be failing because linux-x64 runtime packs are being used for browser-wasm here instead of musl-variants. @lewing Is this something you know about?

[lewing]

mono-aot-cross is a native binary in one of the workload packs. It should be there after a workload install, I'm not sure why it would be missing.

[baronfel]

I'll see if I can grab a binlog from the dockerfile and see if anything stands out, then.

[baronfel]

@lewing it does exist on disk, but the thing that's happening is the linux-x64 version of the pack is being downloaded, not the linux-musl-x64 version. As a result, the mono-aot-cross binary doesn't launch and we get the 'not found' message (which is really a 'couldn't launch' message).

[lewing]

ok, if that is the case we have a different problem, there is no linux-musl-x64 pack for mono-aot-cross and if we were to produce one does the workload resolver know the difference? What is the error when it fails to run?

[lewing]

cc @directhex

[directhex]

We aren't building cross compilers for musl. I'll throw up a PR to try enabling it.

[directhex]

dotnet/runtime#87841

[boukenka]

Hello. I am facing the same issue. I am using 7.0.403-alpine3.18 and 7.0.13-alpine3.18 :

/usr/share/dotnet/packs/Microsoft.NET.Runtime.WebAssembly.Sdk/7.0.13/Sdk/WasmApp.Native.targets(283,5): error MSB3073: The command ""/usr/share/dotnet/packs/Microsoft.NETCore.App.Runtime.AOT.linux-x64.Cross.browser-wasm/7.0.13/Sdk/../tools/mono-aot-cross" --print-icall-table > "/src/Client/obj/Release/net7.0/wasm/for-build/runtime-icall-table.h"" exited with code 127. [/src/Client/...csproj]

Any workaround ? I know it can be solved by using Debian 12 instead.

PS : The error is happening during the execution of the command : RUN dotnet build

[lbussell]

I am hitting this issue today with Alpine 3.18 + .NET 8 compiling a Blazor WASM app. @directhex it seems your fix in runtime may not have worked for Alpine?

• Dockerfile
  • I am using Docker images from Add libatomic to 8.0+ SDK images dotnet-docker#5066.
• Repro repo

Error output:

 > [publish 2/2] RUN dotnet publish "BlazorApp1.csproj" -c Release -o /app/publish /p:UseAppHost=false:
1.533 MSBuild version 17.8.3+195e7f5a3 for .NET
2.436   Determining projects to restore...
2.966   All projects are up-to-date for restore.
3.965   BlazorApp1 -> /src/bin/Release/net8.0/BlazorApp1.dll
3.968   BlazorApp1 (Blazor output) -> /src/bin/Release/net8.0/wwwroot
4.559   Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
4.569   Optimizing assemblies for size. This process might take a while.
17.18   Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
17.28   AOT'ing 32 assemblies
18.27 /usr/share/dotnet/packs/Microsoft.NET.Runtime.WebAssembly.Sdk/8.0.0/Sdk/WasmApp.Native.targets(686,5): error : Precompiling failed for /src/obj/Release/net8.0/wasm/for-publish/aot-in/Microsoft.AspNetCore.Components.dll: An error occurred trying to start process '/usr/share/dotnet/packs/Microsoft.NETCore.App.Runtime.AOT.linux-x64.Cross.browser-wasm/8.0.0/Sdk/../tools/mono-aot-cross' with working directory '/src/obj/Release/net8.0/wasm/for-publish/aot-in'. No such file or directory [/src/BlazorApp1.csproj]
... 31 more times

/cc @lewing @baronfel