.NET Core Attach support for Windows containers

[v-dantch]

OS: Windows
Build Version: 20200225.1
Regression: Not a Regression

Repro Steps:

1. Switch to Windows Containers mode.
2. Create a ASP .NET Core web app by "dotnet new mvc".
3. Open this project in VS Code --> Prompt to add the required assets --> Yes.
4. F1 --> Type and select "Docker: Add Docker Files to Workspace" --> ASP .NET Core --> Windows--> Include optional Docker Compose files --> Enter ports: the default 80,443.
5. Right click the docker-compose.yml --> Select "Compose Up".
6. Open launch.json file --> Add "Docker: .NET Core Attach (Preview)" configuration.
7. Debug with "Docker: .NET Core Attach (Preview)" configuration.

Expect:
Succeed to debug.

Actual:
Fail to debug with error "Process exited with code 126".

[ravipal]

Attach to windows container is not supported. But we should improve the experience by validating the target container OS and provide appropriate error message to user.

[bwateratmsft]

Is it not possible, period, or could users set up the debugger themselves and make it work?

[ravipal]

We don't support windows out of the box. But user can still debug with the below steps.

1. Run 'Add Docker Files to Workspace' to create the docker-compose.debug.yml
2. Add the "Docker .NET Core Attach (Preview)" to launch.json
3. Download (https://aka.ms/getvsdbgps1) and install the vsdbg on the host machine at ~/.vsdbg
   4 Update the launch config "Docker .NET Core Attach (Preview)" by adding debuggerPath as shown below.
   "netCore": {
   "debuggerPath": "C:\remote_debugger\win7-x64\latest\vsdbg"
   }
4. Now "Docker .NET Core Attach (Preview)" will attach the windows container.

[dbreshears]

Let's emit a better error message and the above steps should be added to the troubleshooting page. Confirm and/or add telemetry for Windows attach vs. Linux

[ravipal]

Since now we copy the debugger from host machine to container. We could support the debugger for windows.