This action sets up a .NET CLI environment for use in actions by:

• optionally downloading and caching a version(s) of dotnet by SDK version(s) and adding to PATH
• registering problem matchers for error output
• setting up authentication to private package sources like GitHub Packages

Note: GitHub hosted runners have some versions of the .NET SDK preinstalled. Installed versions are subject to change. Please refer to the documentation: Software installed on github hosted runners for .NET SDK versions that are currently available.

See action.yml

Basic:

steps:
- uses: actions/checkout@v4
- uses: actions/setup-dotnet@v4
  with:
    dotnet-version: '3.1.x'
- run: dotnet build <my project>

Warning: Unless a concrete version is specified in the global.json file, the latest .NET version installed on the runner (including preinstalled versions) will be used by default. Please refer to the documentation for the currently preinstalled .NET SDK versions.

Multiple version installation:

steps:
- uses: actions/checkout@v4
- name: Setup dotnet
  uses: actions/setup-dotnet@v4
  with:
    dotnet-version: | 
      3.1.x
      5.0.x
- run: dotnet build <my project>

The dotnet-version input supports following syntax:

• A.B.C (e.g 6.0.400, 7.0.100-preview.7.22377.5) - installs exact version of .NET SDK
• A.B or A.B.x (e.g. 3.1, 3.1.x) - installs the latest patch version of .NET SDK on the channel 3.1, including prerelease versions (preview, rc)
• A or A.x (e.g. 3, 3.x) - installs the latest minor version of the specified major tag, including prerelease versions (preview, rc)
• A.B.Cxx (e.g. 6.0.4xx) - available since .NET 5.0 release. Installs the latest version of the specific SDK release, including prerelease versions (preview, rc).

This input sets up the action to install the latest build of the specified quality in the channel. The possible values of dotnet-quality are: daily, signed, validated, preview, ga.

Note: dotnet-quality input can be used only with .NET SDK version in 'A.B', 'A.B.x', 'A', 'A.x' and 'A.B.Cxx' formats where the major version is higher than 5. In other cases, dotnet-quality input will be ignored.

steps:
- uses: actions/checkout@v4
- uses: actions/setup-dotnet@v4
  with:
    dotnet-version: '6.0.x'
    dotnet-quality: 'preview'
- run: dotnet build <my project>

setup-dotnet action can read .NET SDK version from a global.json file. Input global-json-file is used for specifying the path to the global.json. If the file that was supplied to global-json-file input doesn't exist, the action will fail with error.

Note: In case both dotnet-version and global-json-file inputs are used, versions from both inputs will be installed.

steps:
- uses: actions/checkout@v4
- uses: actions/setup-dotnet@v4
  with:
    global-json-file: csharp/global.json
- run: dotnet build <my project>
  working-directory: csharp

The action has a built-in functionality for caching and restoring dependencies. It uses toolkit/cache under the hood for caching global packages data but requires less configuration settings. The cache input is optional, and caching is turned off by default.

The action searches for NuGet Lock files (packages.lock.json) in the repository root, calculates their hash and uses it as a part of the cache key. If lock file does not exist, this action throws error. Use cache-dependency-path for cases when multiple dependency files are used, or they are located in different subdirectories.

Warning: Caching NuGet packages is available since .NET SDK 2.1.500 and 2.2.100 as the NuGet lock file is available only for NuGet 4.9 and above.

steps:
- uses: actions/checkout@v4
- uses: actions/setup-dotnet@v4
  with:
    dotnet-version: 6.x
    cache: true
- run: dotnet restore --locked-mode

Note: This action will only restore global-packages folder, so you will probably get the NU1403 error when running dotnet restore. To avoid this, you can use DisableImplicitNuGetFallbackFolder option.

<PropertyGroup>
  <DisableImplicitNuGetFallbackFolder>true</DisableImplicitNuGetFallbackFolder>
</PropertyGroup>

Note: Use NUGET_PACKAGES environment variable if available. Some action runners already has huge libraries. (ex. Xamarin)

env:
  NUGET_PACKAGES: ${{ github.workspace }}/.nuget/packages
steps:
- uses: actions/checkout@v4
- uses: actions/setup-dotnet@v4
  with:
    dotnet-version: 6.x
    cache: true
- run: dotnet restore --locked-mode

env:
  NUGET_PACKAGES: ${{ github.workspace }}/.nuget/packages
steps:
- uses: actions/checkout@v4
- uses: actions/setup-dotnet@v4
  with:
    dotnet-version: 6.x
    cache: true
    cache-dependency-path: subdir/packages.lock.json
- run: dotnet restore --locked-mode

Using setup-dotnet it's possible to use matrix syntax to install several versions of .NET SDK:

jobs:
  build:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        dotnet: [ '2.1.x', '3.1.x', '5.0.x' ]
    name: Dotnet ${{ matrix.dotnet }} sample
    steps:
      - uses: actions/checkout@v4
      - name: Setup dotnet
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: ${{ matrix.dotnet }}
      - name: Execute dotnet
        run: dotnet build <my project>

Note: Unless a concrete version is specified in the global.json file, the latest .NET version installed on the runner (including preinstalled versions) will be used by default. To control this behavior you may want to use temporary global.json files:

Matrix testing with temporary global.json creation

jobs:
  build:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        dotnet: [ '2.1.x', '3.1.x', '5.0.x' ]
    name: Dotnet ${{ matrix.dotnet }} sample
    steps:
      - uses: actions/checkout@v4
      - name: Setup dotnet
        uses: actions/setup-dotnet@v4
        id: stepid
        with:
          dotnet-version: ${{ matrix.dotnet }}
      - name: Create temporary global.json
        run: echo '{"sdk":{"version": "${{ steps.stepid.outputs.dotnet-version }}"}}' > ./global.json
      - name: Execute dotnet
        run: dotnet build <my project>

steps:
- uses: actions/checkout@v4
- uses: actions/setup-dotnet@v4
  with:
    dotnet-version: '3.1.x'
    source-url: https://nuget.pkg.github.com/<owner>/index.json
  env:
    NUGET_AUTH_TOKEN: ${{secrets.GITHUB_TOKEN}}
- run: dotnet build <my project>
- name: Create the package
  run: dotnet pack --configuration Release <my project>
- name: Publish the package to GPR
  run: dotnet nuget push <my project>/bin/Release/*.nupkg

- uses: actions/setup-dotnet@v4
  with:
    source-url: https://pkgs.dev.azure.com/<your-organization>/_packaging/<your-feed-name>/nuget/v3/index.json
  env:
    NUGET_AUTH_TOKEN: ${{secrets.AZURE_DEVOPS_PAT}} # Note, create a secret with this name in Settings
- name: Publish the package to Azure Artifacts
  run: dotnet nuget push <my project>/bin/Release/*.nupkg

- uses: actions/setup-dotnet@v4
  with:
    dotnet-version: 3.1.x
- name: Publish the package to nuget.org
  run: dotnet nuget push */bin/Release/*.nupkg -k $NUGET_AUTH_TOKEN -s https://api.nuget.org/v3/index.json
  env:
    NUGET_AUTH_TOKEN: ${{ secrets.NUGET_TOKEN }}

Note: It's the only way to push a package to nuget.org feed for macOS/Linux machines due to API key config store limitations.

Using the dotnet-version output it's possible to get the installed by the action .NET SDK version.

Single version installation

In case of a single version installation, the dotnet-version output contains the version that is installed by the action.

    - uses: actions/setup-dotnet@v4
      id: stepid
      with:
        dotnet-version: 3.1.422
    - run: echo '${{ steps.stepid.outputs.dotnet-version }}' # outputs 3.1.422

Multiple version installation

In case of a multiple version installation, the dotnet-version output contains the latest version that is installed by the action.

    - uses: actions/setup-dotnet@v4
      id: stepid
      with:
        dotnet-version: | 
          3.1.422
          5.0.408
    - run: echo '${{ steps.stepid.outputs.dotnet-version }}' # outputs 5.0.408

Installation from global.json

When the dotnet-version input is used along with the global-json-file input, the dotnet-version output contains the version resolved from the global.json.

    - uses: actions/setup-dotnet@v4
      id: stepid
      with:
        dotnet-version: | 
          3.1.422
          5.0.408
        global-json-file: "./global.json" # contains version 2.2.207
    - run: echo '${{ steps.stepid.outputs.dotnet-version }}' # outputs 2.2.207

A boolean value to indicate an exact match was found for the cache key (follows actions/cache)

Some environment variables may be necessary for your particular case or to improve logging. Some examples are listed below, but the full list with complete details can be found here: https://docs.microsoft.com/en-us/dotnet/core/tools/dotnet-environment-variables

The default values of the DOTNET_INSTALL_DIR and NUGET_PACKAGES environment variables depend on the operation system which is used on a runner:

Example usage of environment variable:

build:
  runs-on: ubuntu-latest
  env:
    DOTNET_INSTALL_DIR: "path/to/directory"
    NUGET_PACKAGES: ${{ github.workspace }}/.nuget/packages
  steps:
    - uses: actions/checkout@main
    - uses: actions/setup-dotnet@v4
      with:
        dotnet-version: '3.1.x'
        cache: true

The scripts and documentation in this project are released under the MIT License

Contributions are welcome! See Contributor's Guide