.NET Core 3.0 SDK Docker images now contain PowerShell Core

PowerShell Core has been added to the .NET Core 3.0 SDK Docker container images as part of .NET Core 3.0 Preview 4. PowerShell Core was added as a result of and resolves dotnet/dotnet-docker #360 . It has been added for both Linux and Nano Server container images, but only for SDK images.

PowerShell Core is a cross-platform (Windows, Linux, and macOS) automation and configuration tool/framework that works well with your existing tools and is optimized for dealing with structured data (e.g. JSON, CSV, XML, etc.), REST APIs, and object models. It includes a command-line shell, an associated scripting language and a framework for processing cmdlets.

You can try out PowerShell Core, as part of the .NET Core SDK container image, by running the following Docker command:

docker run --rm mcr.microsoft.com/dotnet/core/sdk:3.0 pwsh -c Write-Host "Hello Powershell"

There are two main scenarios that having PowerShell inside the .NET Core SDK container image enables, which were not otherwise possible:

• Write .NET Core application Dockerfiles with PowerShell syntax for any OS.
• Write .NET Core application/library build logic that can be easily containerized.

Example syntax for launching PowerShell for a (volume-mounted) containerized build:

• docker run -it -v c:\myrepo:/myrepo -w /myrepo mcr.microsoft.com/dotnet/core/sdk:3.0 pwsh build.ps1
• docker run -it -v c:\myrepo:/myrepo -w /myrepo mcr.microsoft.com/dotnet/core/sdk:3.0 ./build.ps1

For the second example to work, on Linux, the .ps1 file needs to have the following pattern, and needs to be formatted with Unix (LF) not Windows (CRLF) line endings:

#!/usr/bin/env pwsh
Write-Host "test"

If you are new to PowerShell and would like to learn more, we recommend reviewing the getting started documentation.

Note: PowerShell Core is now available as part of .NET Core 3.0 SDK container images. It is not part of the .NET Core 3.0 SDK.