setup-go

The action resolves the requested version using the following priority order:

1. Local cache: Checks the local tool cache for a matching semver version.
2. go-versions repository: If not in the local cache, it pulls the version manifest from the main branch of the actions/go-versions repository.
3. Direct download: If the lookup fails, it falls back to downloading directly from the official Go distribution site.

Note: The action uses executable binaries built by the Go team and does not build Go binaries from source code.

The action provides built-in caching for Go modules and build outputs using toolkit/cache. Caching is enabled by default (cache: true).

• Default behavior: The action looks for go.mod in the repository root and uses its hash as part of the cache key.
• Custom dependency path: If you have multiple dependency files or they are in subdirectories, use the cache-dependency-path input. This input supports glob patterns.
• Disabling cache: Set cache: false to disable caching.

If caching fails, the action logs a warning and continues the workflow execution.

- uses: actions/setup-go@v7
  with:
    cache: true
    cache-dependency-path: 'go.sum'

To avoid reusing caches across incompatible builds (e.g., different OS or architecture), include files that capture build settings like GOOS or GOARCH in the cache-dependency-path. This ensures separate caches per target platform.

env:
  GOOS: ...
  GOARCH: ...

steps:
  - run: echo "$GOOS $GOARCH" > env.txt

  - uses: actions/checkout@v7
  - uses: actions/setup-go@v7
    with:
      go-version: '1.25'
      cache-dependency-path: |
        go.sum
        env.txt
  - run: go run hello.go    

Reviewing pull requests is a way to help maintain quality and support contributors.

How to review:

• Navigate to the pull requests tab.
• Ensure you are familiar with the code or documentation being updated (except for minor changes like spelling).
• Use GitHub's review functionality to ask clarifying questions, point out errors, or suggest alternatives.
• Submit your review as a comment, an approval, or a request for changes.
• Be respectful and kind to contributors. Distinguish between "nitpicks" (minor suggestions) and actual blockers to merging.

To ensure proper functionality (such as checking out code and installing dependencies), it is recommended to set the following permissions in your workflow:

permissions:
  contents: read

You can contribute by helping users resolve questions in the issue tracker.

Best Practices:

• Only respond to issues you are confident you can answer accurately.
• Refer to past issues with accepted answers and link to them in your replies.
• Be kind and patient with users.
• Once a discussion is resolved, ask the original filer or a maintainer to close the issue.
• If a user violates the Code of Conduct, follow the Enforcement section of the Code of Conduct.

Use actions/setup-go@v7 to set up a Go environment. This action can download and cache a specific Go version, add it to the PATH, cache Go modules and build outputs, and register problem matchers for error output.

Basic Usage:

steps:
  - uses: actions/checkout@v7
  - uses: actions/setup-go@v7
    with:
      go-version: '1.25'
  - run: go run hello.go

You can use aliases to resolve Go versions:

• stable: Resolves to the latest stable version from the go-versions manifest.
• oldstable: Resolves to the latest patch release of the previous stable Go minor version (e.g., if 1.25.x is stable, oldstable resolves to 1.24.x).

Note: Using these aliases is equivalent to setting check-latest: true with the corresponding minor version.

# Use latest stable
steps:
  - uses: actions/checkout@v7
  - uses: actions/setup-go@v7
    with:
      go-version: 'stable'
  - run: go run hello.go

# Use latest oldstable
steps:
  - uses: actions/checkout@v7
  - uses: actions/setup-go@v7
    with:
      go-version: 'oldstable'
  - run: go run hello.go

To reduce cache writes and avoid race conditions during parallel builds, you can disable automatic caching in setup-go and use actions/cache/restore manually. This allows you to create the cache in one specific build and simply restore it in others.

jobs:
  build:
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        os: [ubuntu-latest, macos-latest, windows-latest]
    steps:
      - uses: actions/checkout@v7
      - name: Setup go
        id: setup-go
        uses: actions/setup-go@v7
        with:
          go-version: '1.25.5'
          cache: false
      # ... (manual steps to set env vars and restore via actions/cache/restore@v5) ...

Use the go-version input to define which Go version to install. You can provide an exact version for repeatable builds, a major/minor version to use the latest patch, or pre-release versions (beta/RC).

Note: Specifying an exact patch version (e.g., 1.25.5) may increase setup time if that specific version is not already pre-installed on the runner. Using just a major/minor version (e.g., 1.25) is faster as it leverages pre-installed versions on the runner.

# Exact version for repeatable builds
steps:
  - uses: actions/checkout@v7
  - uses: actions/setup-go@v7
    with:
      go-version: '1.25.5'
  - run: go run hello.go

# Major/minor version (uses latest patch)
steps:
  - uses: actions/checkout@v7
  - uses: actions/setup-go@v7
    with:
      go-version: '1.25'
  - run: go run hello.go