Publishing directly to Docker Hub

[pfedotovsky]

Hi,

I want to share my experience with publishing directly to the Docker Hub. I hope it'll be helpful for someone and used to update the documentation: https://github.com/dotnet/sdk-container-builds/blob/main/docs/RegistryAuthentication.md.

I'm using macOS Ventura with an Apple M1 chip.
First, I've found that they're at least three Docker Hub registry URLs which is confusing:

1. docker.io: seems to be used by default in docker on macOS
2. registry-1.docker.io: mentioned in https://github.com/dotnet/sdk-container-builds/blob/main/docs/RegistryAuthentication.md
3. registry.hub.docker.com: used when publishing from Visual Studio on Windows

To authenticate with registries, I used docker login <registry-name>, i.e., docker login registry.hub.docker.com
To publish, I used the command:
dotnet publish --os linux --arch x64 -c Release /p:ContainerRegistry=<registry-name> /p:ContainerImageName=<dockerhub-username>/<repository-name>
Example:
dotnet publish --os linux --arch x64 -c Release /p:ContainerRegistry=registry.hub.docker.com /p:ContainerImageName=pfedotovsky/dotnetru-appservice

Now, the registry.hub.docker.com and registry-1.docker.io are working correctly, while with docker.io, the dotnet publish command executes successfully, but no package is found on Docker Hub.

[baronfel]

Thanks for this feedback @pfedotovsky - let me make sure I understand the takeaway here.

• We should mention all three Docker URIs that look like registries to users in our docs
• We should clarify that either of the registry-1.docker.io or registry.hub.docker.com registries should be used when logging in in our docs
• (Bonus) we should add some registry-specific checks (like have been done for Amazon Elastic Container Registry endpoints) that issue a warning
  • if the docker-io URI is used as the ContainerRegistry (because it won't work), or
  • the registry* Docker URIs are used as the ContainerRegistry but we only have credentials for docker.io (because the user used a 'normal' docker login command)

Is there anything else you'd like to see?

[pfedotovsky]

@baronfel, thank you for the summary! Looks great, I don't have anything to add 😊