gradle-build-action/README.md

Execute Gradle builds in GitHub Actions workflows

This GitHub Action can be used to execute a Gradle build on any platform supported by GitHub Actions.

Usage

The following workflow will run ./gradlew build using the wrapper from the repository on ubuntu, macos and windows. The only prerequisite is to have Java installed: you define the version of Java you need to run the build using the actions/setup-java action.

# .github/workflows/gradle-build-pr.yml
name: Run Gradle on PRs
on: pull_request
jobs:
  gradle:
    strategy:
      matrix:
        os: [ubuntu-latest, macos-latest, windows-latest]
    runs-on: ${{ matrix.os }}
    steps:
    - uses: actions/checkout@v2
    - uses: actions/setup-java@v1
      with:
        java-version: 11
    - uses: gradle/gradle-build-action@v1
      with:
        arguments: build

Gradle arguments

The arguments input can used to pass arbitrary arguments to the gradle command line.

Here are some valid examples:

arguments: build
arguments: check --scan
arguments: some arbitrary tasks
arguments: build -PgradleProperty=foo
arguments: build -DsystemProperty=bar
....

See gradle --help for more information.

If you need to pass environment variables, simply use the GitHub Actions workflow syntax:

- uses: gradle/gradle-build-action@v1
  env:
    CI: true

Run a build from a different directory

- uses: gradle/gradle-build-action@v1
  with:
    build-root-directory: some/subdirectory

Use a specific gradle executable

 - uses: gradle/gradle-build-action@v1
   with:
     gradle-executable: path/to/gradle

Use a Gradle wrapper from a different directory

 - uses: gradle/gradle-build-action@v1
   with:
     gradle-executable: path/to/gradlew

NOTE: The wrapper-directory input has been deprecated. Use gradle-executable instead.

Setup and use a declared Gradle version

 - uses: gradle/gradle-build-action@v1
   with:
     gradle-version: 6.5

gradle-version can be set to any valid Gradle version.

Moreover, you can use the following aliases:

Alias	Selects
wrapper	The Gradle wrapper's version (default, useful for matrix builds)
current	The current stable release
release-candidate	The current release candidate if any, otherwise fallback to current
nightly	The latest nightly, fails if none.
release-nightly	The latest release nightly, fails if none.

This can be handy to, for example, automatically test your build with the next Gradle version once a release candidate is out:

# .github/workflows/test-gradle-rc.yml
name: Test latest Gradle RC
on:
  schedule:
    - cron: 0 0 * * * # daily
jobs:
  gradle-rc:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2
    - uses: actions/setup-java@v1
      with:
        java-version: 11
    - uses: gradle/gradle-build-action@v1
      with:
        gradle-version: release-candidate
        arguments: build --dry-run # just test build configuration

Caching

This action provides 3 levels of caching to help speed up your GitHub Actions:

• distributions caches any downloaded Gradle zips, including any downloaded wrapper versions, saving time downloading Gradle distributions ;
• dependencies caches the dependencies, saving time downloading dependencies ;
• configuration caches the build configuration, saving time configuring the build.

Only the first one, caching downloaded distributions, is enabled by default. Future versions of this action will enable all caching by default.

You can control which level is enabled as follows:

distributions-cache-enabled: true
dependencies-cache-enabled: true
configuration-cache-enabled: true

NOTE: The wrapper-cache-enabled flag has been deprecated, replaced by distributions-cache-enabled which enables caching for all downloaded distributions, including Gradle wrapper downloads.

The distributions cache is simple and can't be configured further.

The dependencies and configuration cache will compute a cache key in a best effort manner. Keep reading to learn how to better control how they work.

Note that enabling configuration cache without thee dependencies cache is not permitted, since a hit in the configuration cache assumes that dependencies are already present in the local dependencies cache.

Configuring the dependencies and configuration caches

Both the dependencies and configuration caches use the same default configuration:

They use the following inputs to calculate the cache key:

**/*.gradle
**/*.gradle.kts
**/gradle.properties
gradle/**

This is a good enough approximation. They restore cached state even if there isn't an exact match.

If the defaults don't suit your needs you can override them with the following inputs:

dependencies-cache-key: |
  **/gradle.properties
  gradle/dependency-locks/**  
dependencies-cache-exact: true
configuration-cache-key: |
  **/gradle.properties
  gradle/dependency-locks/**  
configuration-cache-exact: true

Coming up with a good cache key isn't trivial and depends on your build. The above example isn't realistic. Stick to the defaults unless you know what you are doing.

If you happen to use Gradle dependency locking you can make the dependencies cache more precise with the following configuration:

dependencies-cache-enabled: true
dependencies-cache-key: gradle/dependency-locks/**
dependencies-cache-exact: true

Using the caches read-only

Cache storage space is limited for GitHub actions, and writing new cache entries can trigger the deletion of exising entries. In some circumstances, it makes sense for a Gradle invocation to use any existing cache entries but not to write and changes back. For example, you may want to write cache entries for builds on your main branch, but not for any PR build invocations.

Use the following configuration to avoid writing cache entries for the action invocation:

cache-read-only: true

Build scans

If your build publishes a build scan the gradle-build-action action will emit the link to the published build scan as an output named build-scan-url.

You can then use that link in subsequent actions of your workflow.

For example:

# .github/workflows/gradle-build-pr.yml
name: Run Gradle on PRs
on: pull_request
jobs:
  gradle:
    strategy:
      matrix:
        os: [ubuntu-latest, macos-latest, windows-latest]
    runs-on: ${{ matrix.os }}
    steps:
    - uses: actions/checkout@v2
    - uses: actions/setup-java@v1
      with:
        java-version: 11
    - uses: gradle/gradle-build-action@v1
      with:
        arguments: build
      id: gradle
    - name: "Comment build scan url"
      uses: actions/github-script@v3
      if: github.event_name == 'pull_request' && failure()
      with:
        github-token: ${{secrets.GITHUB_TOKEN}}
        script: |
          github.issues.createComment({
            issue_number: context.issue.number,
            owner: context.repo.owner,
            repo: context.repo.repo,
            body: '❌ ${{ github.workflow }} failed: ${{ steps.gradle.outputs.build-scan-url }}'
          })