Make csharp.listRemoteProcess support images without ps

[gregg-miskelly]

Issue Description

The csharp.listRemoteProcess command would be helpful in Docker extension scenarios, because our debugging all happens through a pipe program (namely, docker exec). However, the implementation of it doesn't work in the Debian .NET base image because ps isn't present.

Steps to Reproduce

1. Scaffold a .NET (Core) app
2. With the C# extension, add the build and debug assets
3. With the Docker extension, do Add Dockerfiles.... Say "Yes" to Compose files.
4. Right click docker-compose.yaml and do Compose Up.
5. Go to the Debug tab. Add a debug configuration for "Docker .NET Core Attach (Preview)". Add "processId": "${command:csharp.listRemoteProcess}" to that config. (Ordinarily this isn't needed since only one dotnet process exists in the container, but in some scenarios--like dotnet watch--more than one exists)
6. F5 that config

Expected Behavior

Remote processes are listed to pick from

Actual Behavior

Error popup reading "See remote-attach output".

On a Debian image:

Executing: docker exec -i netcore2020_netcore2020_1 sh -s < "c:\Users\bwater\.vscode\extensions\ms-dotnettools.csharp-1.23.1\scripts\remoteProcessPickerScript"
Linux
stderr: sh: 1: ps: not found
Error Message: Command failed: docker exec -i netcore2020_netcore2020_1 sh -s < "c:\Users\bwater\.vscode\extensions\ms-dotnettools.csharp-1.23.1\scripts\remoteProcessPickerScript"
sh: 1: ps: not found

Changing the implementation of this to avoid ps, or adding an alternative command that uses OS APIs*, would enable this scenario.

*Note: VSDBG is present in the container so scripts are not the only option

Work around

Modify your docker file to add the procps package.

[ssaraswati]

This is implemented now in 1.25.0 and should work in both Alpine and Debian based Docker images

[JoeRobich]

Thanks for confirming @ssaraswati. Closing this issue.