dotnet-subset is a .NET tool that copies a subset of files from a repository to a directory.

The tool is mainly used in Dockerfiles to optimize the docker build caching for "dotnet restore" instructions.

To learn more about the motivation behind dotnet-subset, please read the related blog post.

• Supports a single project or a solution file as input.
• Copies all the required files for the root projects, including their project dependencies transitively.
• Copies imported MSBuild files, including Directory.Build.props and Directory.Build.targets.
• For each required project, copies all NuGet configuration files involved in computing its effective NuGet settings. See How NuGet settings are applied. dotnet-subset also supports custom NuGet configuration filepath defined in the project's csproj.
• For each required project, copies the NuGet lock file and support the NuGetLockFilePath property. See https://learn.microsoft.com/en-us/nuget/consume-packages/package-references-in-project-files#lock-file-extensibility.
• Only copies files under the specified root, while maintaining their relative path to it.

dotnet tool install --global dotnet-subset

Prerequisite: .NET SDK 3.1 or newer

1. Clone this repository
2. Open a terminal in the repository's root
3. dotnet pack --configuration Release --version-suffix local
4. dotnet tool update dotnet-subset --global --prerelease --configfile .config/nuget-local-install-release.config

Description:
  Create a subset for the restore operation.

Usage:
  dotnet-subset restore <projectOrSolution> [options]

Arguments:
  <projectOrSolution>  Project or solution to restore.

Options:
  --root-directory <root-directory> (REQUIRED)  Directory from where the files will be copied, usually the
                                                repository's root.
  --output <output> (REQUIRED)                  Directory where the subset files will be copied,
                                                preserving the original hierarchy.
  -?, -h, --help                                Show help and usage information

Example with a project:

dotnet subset restore /source/complexapp/complexapp.csproj --root-directory /source/ --output /tmp/restore_subset/

Example with a solution:

dotnet subset restore /source/complexapp.sln --root-directory /source/ --output /tmp/restore_subset/

Please check these pull requests to see how to use dotnet-subset in your Dockerfile:

• https://github.com/othmane-kinane-nw/eShopOnContainers/pull/1/files?diff=unified&w=0
• https://github.com/othmane-kinane-nw/modular-monolith-with-ddd/pull/1/files?diff=unified&w=0
• https://github.com/othmane-kinane-nw/dotnet-docker/pull/1/files?diff=unified&w=0

• Add tests
• Refactor the codebase
• Add "build" algorithm
• Automate the deployment to NuGet

Copyright © Nimbleways, Othmane Kinane and contributors.

dotnet-subset is provided as-is under the MIT license. For more information see LICENSE.

• For Microsoft.Build, see https://github.com/dotnet/msbuild/blob/main/LICENSE
• For Microsoft.Build.Locator, see https://github.com/microsoft/MSBuildLocator/blob/master/LICENSE
• For System.CommandLine, see https://github.com/dotnet/command-line-api/blob/main/LICENSE.md