Support pivoting on OS platform and Architecture for image selection

[baronfel]

Right now we explicitly support Linux/x64 container images - we should instead take into account the OS and Architecture the user provides and pick the correct 'base image' from the manifest list (if there is one on the base image).

We'll need to investigate what level of impact this has on picking the correct base image, but this will also have an impact on

• WorkingDirectory
• EntryPoint

Overlaps with #117

[bgiromini]

I assume this is still not supported with the release of dotnet 7 today?

[rainersigwald]

@bgiromini correct--the 0.2 version of the package is still linux-x64 only. But this is definitely still on the to-do list!

[MrRickwi]

I tried to use debian.11 as OS - which is still Linux - but didn't work. Would be nice to see at least support for all Linux-like OSs in very near future - because we have packages in our project which have nothing in runtimes/linux-x64, but e.g. runtimes/debian.11-x64

[baronfel]

Thanks for the feedback @MrRickwi - I'm working on this in #247 and one of the open questions I was thinking about was 'how seriously do we need to handle RID support/compatibility'? Your response makes me think we need to fully support it.

[Zigby]

I was hoping it would work to publish arm images like this

dotnet publish --os linux --arch arm64 

Is it correct that this issue will address publishing linux-arm64?

[baronfel]

Yep, exactly - right now when you publish, if the image you choose (let's take mcr.microsoft.com/dotnet/aspnet:7.0 as our example) is a 'manifest list' (meaning it supports multiple architectures), we don't understand that and instead we end up picking the 'first' image in the manifest list. This is usually a linux-x64 image. You as a user could explicitly pick an arm64 version of this image right now via setting the ContainerBaseImage property, but we would instead like to read the RID that you specify and use it to pick the most appropriate base image if the image you chose supports multiple architectures.

[Zigby]

If I understood correctly I should be able to create arm64 images by explicitly specifying the ContainerBaseImage. I cannot get it to work so here is what I am doing ...
I am omitting the architecture from the command line
dotnet publish --os linux -p:PublishProfile=DefaultContainer
and specify the container image in the csproj file (just picked what I thought would be appropriate)

 <ContainerBaseImage>mcr.microsoft.com/dotnet/aspnet:7.0-bullseye-slim-arm64v8</ContainerBaseImage>

I get the following error message
The Microsoft.NET.Build.Containers package does not (yet) support publishing for linux-arm64

If I specify "--arch x64" it produces an image but it does not properly run on my arm computer.

Do I need to wait for a fix, or am I doing it wrong?

[baronfel]

@Zigby you're exactly right - I forgot we explicitly locked that down for the initial release here. My apologies! So yes, you're blocked until we release #247.

[Zigby]

Thanks for the clarification and prompt response. I will stick to docker files for a little longer...

[baronfel]

We're currently planning to freeze the RID graph and make RIDs no longer distro-specific. As a result, we're not going to go to full detail in this project to support e.g. ubuntu22.04-x64 for example. Instead, for publishing containers you'd specify linux-x64 (or linux-arm64 or another supported RID for the container manifest list). If a RID is specified that there is not match for on the discovered manifest list, an error will be raised specifying the valid RIDs for the manifest list.

[baronfel]

Fixed in #247, out now in version 0.3.2 of the package!