Implementation of caching functionality for setup-go action (#228)

Add note about golang building process

.gitattributes

@@ -0,0 +1,2 @@
+* text=auto
+.licenses/** -diff linguist-generated=true

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,38 @@
+---
+name: Bug report
+about: Create a bug report
+title: ''
+labels: bug, needs triage
+assignees: ''
+
+---
+
+<!--- Please direct any generic questions related to actions to our support community forum at https://github.community/c/code-to-cloud/github-actions/41 --->
+<!--- Before opening up a new bug report, please make sure to check for similar existing issues -->
+
+**Description:**
+A clear and concise description of what the bug is.
+
+**Action version:**
+Specify the action version
+
+**Platform:**
+- [ ] Ubuntu
+- [ ] macOS
+- [ ] Windows
+
+**Runner type:**
+- [ ] Hosted
+- [ ] Self-hosted
+
+**Tools version:**
+<!--- Please specify go version -->
+
+**Repro steps:**  
+A description with steps to reproduce the issue. If your have a public example or repo to share, please provide the link.
+
+**Expected behavior:**
+A description of what you expected to happen.
+
+**Actual behavior:**
+A description of what is actually happening.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1 @@
+blank_issues_enabled: false

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,18 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: feature request, needs triage
+assignees: ''
+---
+<!--- Please direct any generic questions related to actions to our support community forum at https://github.community/c/code-to-cloud/github-actions/41 --->
+<!--- Before opening up a new feature request, please make sure to check for similar existing issues and pull requests -->
+
+**Description:**
+Describe your proposal.
+
+**Justification:**
+Justification or a use case for your proposal.
+
+**Are you willing to submit a PR?**
+<!--- We accept contributions! -->

.github/pull_request_template.md

@@ -0,0 +1,9 @@
+**Description:**
+Describe your changes.
+
+**Related issue:**
+Add link to the related issue.
+
+**Check list:**
+- [ ] Mark if documentation changes are required.
+- [ ] Mark if tests were added or updated to cover the changes.

.github/workflows/check-dist.yml

@@ -0,0 +1,51 @@
+# `dist/index.js` is a special file in Actions.
+# When you reference an action with `uses:` in a workflow,
+# `index.js` is the code that will run.
+# For our project, we generate this file through a build process from other source files.
+# We need to make sure the checked-in `index.js` actually matches what we expect it to be.
+name: Check dist/
+
+on:
+  push:
+    branches:
+      - main
+    paths-ignore:
+      - '**.md'
+  pull_request:
+    paths-ignore:
+      - '**.md'
+  workflow_dispatch:
+
+jobs:
+  check-dist:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Set Node.js 16.x
+        uses: actions/setup-node@v3
+        with:
+          node-version: 16.x
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Rebuild the dist/ directory
+        run: npm run build
+
+      - name: Compare the expected and actual dist/ directories
+        run: |
+          if [ "$(git diff --ignore-space-at-eol dist/ | wc -l)" -gt "0" ]; then
+            echo "Detected uncommitted changes after build.  See status below:"
+            git diff
+            exit 1
+          fi
+        id: diff
+
+      # If index.js was different than expected, upload the expected version as an artifact
+      - uses: actions/upload-artifact@v3
+        if: ${{ failure() && steps.diff.conclusion == 'failure' }}
+        with:
+          name: dist
+          path: dist/

.github/workflows/licensed.yml

@@ -0,0 +1,28 @@
+name: Licensed
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    name: Check licenses
+    steps:
+      - uses: actions/checkout@v3
+      - name: Set Node.js 16.x
+        uses: actions/setup-node@v3
+        with:
+          node-version: 16.x
+      - run: npm ci
+      - name: Install licensed
+        run: |
+          cd $RUNNER_TEMP
+          curl -Lfs -o licensed.tar.gz https://github.com/github/licensed/releases/download/3.4.4/licensed-3.4.4-linux-x64.tar.gz
+          sudo tar -xzf licensed.tar.gz
+          sudo mv licensed /usr/local/bin/licensed
+      - run: licensed status

.github/workflows/release-new-action-version.yml

@@ -0,0 +1,27 @@
+name: Release new action version
+on:
+  release:
+    types: [released]
+  workflow_dispatch:
+    inputs:
+      TAG_NAME:
+        description: 'Tag name that the major tag will point to'
+        required: true
+
+env:
+  TAG_NAME: ${{ github.event.inputs.TAG_NAME || github.event.release.tag_name }}
+permissions:
+  contents: write
+
+jobs:
+  update_tag:
+    name: Update the major tag to include the ${{ github.event.inputs.TAG_NAME || github.event.release.tag_name }} changes
+    environment:
+      name: releaseNewActionVersion
+    runs-on: ubuntu-latest
+    steps:
+      - name: Update the ${{ env.TAG_NAME }} tag
+        uses: actions/publish-action@v0.1.0
+        with:
+          source-tag: ${{ env.TAG_NAME }}
+          slack-webhook: ${{ secrets.SLACK_WEBHOOK }}

.github/workflows/versions.yml

@@ -1,51 +1,109 @@
-name: go-versions
+name: Validate 'setup-go'
 on:
-    push:
+  push:
-      branches:
+    branches:
-        - master
+      - main
-      paths-ignore:
+    paths-ignore:
-        - '**.md'
+      - '**.md'
-    pull_request:
+  pull_request:
-      paths-ignore:
+    paths-ignore:
-        - '**.md'
+      - '**.md'
+  schedule:
+    - cron: 0 0 * * *
+
 jobs:
-  run:
+  local-cache:
-    name: Go
+    name: Setup local-cache version
-    runs-on: ${{ matrix.operating-system }}
+    runs-on: ${{ matrix.os }}
     strategy:
+      fail-fast: false
       matrix:
-        operating-system: [ubuntu-latest, windows-latest, macos-latest]
+        os: [macos-latest, windows-latest, ubuntu-latest]
+        go: [1.12, 1.13, 1.14]
     steps:
-    - name: Checkout
+      - name: Checkout
-      uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
-    - name: setup-go ^1.13.6
+      - name: setup-go ${{ matrix.go }}
-      uses: ./
+        uses: ./
-      with:
+        with:
-        go-version: ^1.13.6
+          go-version: ${{ matrix.go }}
 
-    - name: validate version 
+      - name: verify go
-      run: go version | grep "go1."
+        run: __tests__/verify-go.sh ${{ matrix.go }}
+        shell: bash
 
-    - name: setup-go 1.13
+  check-latest:
-      uses: ./
+    runs-on: ${{ matrix.os }}
-      with:
+    strategy:
-        go-version: 1.13
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+        go-version: [1.16, 1.17]
+    steps:
+      - uses: actions/checkout@v3
+      - name: Setup Go and check latest
+        uses: ./
+        with:
+          go-version: ${{ matrix.go-version }}
+          check-latest: true
+      - name: Verify Go
+        run: go version
 
-    - name: validate version 
+  go-version-file:
-      run: go version | grep "go1.13."      
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+    steps:
+      - uses: actions/checkout@v3
+      - name: Setup Go and check latest
+        uses: ./
+        with:
+          go-version-file: __tests__/data/go.mod
+      - name: verify go
+        run: __tests__/verify-go.sh 1.14
+        shell: bash
 
-    - name: setup-go 1.12.9
+  setup-versions-from-manifest:
-      uses: ./
+    name: Setup ${{ matrix.go }} ${{ matrix.os }}
-      with:
+    runs-on: ${{ matrix.os }}
-        go-version: 1.12.9
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-latest, windows-latest, ubuntu-latest]
+        go: [1.12.16, 1.13.11, 1.14.3]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
 
-    - name: validate version 
+      - name: setup-go ${{ matrix.go }}
-      run: go version | grep "go1.12.9"
+        uses: ./
+        with:
+          go-version: ${{ matrix.go }}
 
-    - name: dump env
+      - name: verify go
-      shell: bash
+        run: __tests__/verify-go.sh ${{ matrix.go }}
-      run: |
+        shell: bash
-        echo $PATH
+
-        echo go versions in tool cache: 
+  setup-versions-from-dist:
-        echo $(ls $RUNNER_TOOL_CACHE/go)       
+    name: Setup ${{ matrix.go }} ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-latest, windows-latest, ubuntu-latest]
+        go: [1.9, 1.8.6]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: setup-go ${{ matrix.go }}
+        uses: ./
+        with:
+          go-version: ${{ matrix.go }}
+
+      - name: verify go
+        run: __tests__/verify-go.sh ${{ matrix.go }}
+        shell: bash

.github/workflows/workflow.yml

@@ -2,7 +2,7 @@ name: build-test
 on:
   push:
     branches:
-      - master
+      - main
     paths-ignore:
       - '**.md'
   pull_request:
@@ -16,23 +16,24 @@ jobs:
       matrix:
         operating-system: [ubuntu-latest, windows-latest]
     steps:
-    - name: Checkout
+      - name: Checkout
-      uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
-    - name: Setup node 12
+      - name: Setup node 16
-      uses: actions/setup-node@v1
+        uses: actions/setup-node@v3
-      with:
+        with:
-        node-version: 12
+          node-version: 16
+          cache: npm
 
-    - name: npm install
+      - name: npm ci
-      run: npm install
+        run: npm ci
 
-    - name: Lint
+      - name: Lint
-      run: npm run format-check
+        run: npm run format-check
 
-    - name: npm test
+      - name: npm test
-      run: npm test
+        run: npm test
 
-    - name: audit packages
+      - name: audit packages
-      run: npm audit --audit-level=high
+        run: npm audit --audit-level=high
-      if: matrix.operating-system == 'ubuntu-latest'
+        if: matrix.operating-system == 'ubuntu-latest'

.licensed.yml

@@ -0,0 +1,15 @@
+sources:
+  npm: true
+
+allowed:
+  - apache-2.0
+  - bsd-2-clause
+  - bsd-3-clause
+  - isc
+  - mit
+  - cc0-1.0
+  - unlicense
+  - 0bsd
+
+reviewed:
+  npm:

CODEOWNERS

@@ -0,0 +1 @@
+* @actions/actions-service

CODE_OF_CONDUCT.md

@@ -55,7 +55,7 @@ a project may be further defined and clarified by project maintainers.
 ## Enforcement
 
 Instances of abusive, harassing, or otherwise unacceptable behavior may be
-reported by contacting the project team at opensource@github.com. All
+reported by contacting the project team at opensource+actions/setup-go@github.com. All
 complaints will be reviewed and investigated and will result in a response that
 is deemed necessary and appropriate to the circumstances. The project team is
 obligated to maintain confidentiality with regard to the reporter of an incident.

README.md

@@ -1,84 +1,182 @@
 # setup-go
 
-<p align="left">
+[![build-test](https://github.com/actions/setup-go/actions/workflows/workflow.yml/badge.svg)](https://github.com/actions/setup-go/actions/workflows/workflow.yml)
-  <a href="https://github.com/actions/setup-go/actions"><img alt="GitHub Actions status" src="https://github.com/actions/setup-go/workflows/build-test/badge.svg"></a>
+[![Validate 'setup-go'](https://github.com/actions/setup-go/actions/workflows/versions.yml/badge.svg)](https://github.com/actions/setup-go/actions/workflows/versions.yml)
-
-  <a href="https://github.com/actions/setup-go/actions"><img alt="versions status" src="https://github.com/actions/setup-go/workflows/go-versions/badge.svg"></a>  
-</p>
 
 This action sets up a go environment for use in actions by:
 
-- optionally downloading and caching a version of Go by version and adding to PATH
+- Optionally downloading and caching a version of Go by version and adding to `PATH`.
-- registering problem matchers for error output
+- Registering problem matchers for error output.
 
-# V2 Beta
+# V3
 
-The V2 beta offers:
+The V3 edition of the action offers:
-- Proxy Support
+
-- stable input 
+- Adds `GOBIN` to the `PATH`
+- Proxy support
+- Check latest version
+- Caching packages dependencies
 - Bug Fixes (including issues around version matching and semver)
 
-Matching by semver spec:
+The action will first check the local cache for a version match. If a version is not found locally, it will pull it from the `main` branch of the [go-versions](https://github.com/actions/go-versions/blob/main/versions-manifest.json) repository. On miss or failure, it will fall back to downloading directly from [go dist](https://storage.googleapis.com/golang). To change the default behavior, please use the [check-latest input](#check-latest-version).
+
+**Note:** The `setup-go` action uses executable binaries which are built by Golang side. The action does not build golang from source code.
+
+Matching by [semver spec](https://github.com/npm/node-semver):
+
 ```yaml
 steps:
-- uses: actions/checkout@v2
+  - uses: actions/checkout@v3
-- uses: actions/setup-go@v2-beta
+  - uses: actions/setup-go@v3
-  with:
+    with:
-    go-version: '^1.13.1' # The Go version to download (if necessary) and use.
+      go-version: '^1.13.1' # The Go version to download (if necessary) and use.
-- run: go version
+  - run: go version
+```
+
+```yaml
+steps:
+  - uses: actions/checkout@v3
+  - uses: actions/setup-go@v3
+    with:
+      go-version: '>=1.17.0'
+  - run: go version
 ```
 
 Matching an unstable pre-release:
+
 ```yaml
 steps:
-- uses: actions/checkout@v2
+  - uses: actions/checkout@v3
-- uses: actions/setup-go@v2-beta
+  - uses: actions/setup-go@v3
-  with:
+    with:
-    stable: 'false'
+      go-version: '1.18.0-rc.1' # The Go version to download (if necessary) and use.
-    go-version: '1.14.0-rc1' # The Go version to download (if necessary) and use.
+  - run: go version
-- run: go version
+```
+
+```yaml
+steps:
+  - uses: actions/checkout@v3
+  - uses: actions/setup-go@v3
+    with:
+      go-version: '1.16.0-beta.1' # The Go version to download (if necessary) and use.
+  - run: go version
 ```
 
 # Usage
 
 See [action.yml](action.yml)
 
-Basic:
+## Basic
+
 ```yaml
 steps:
-- uses: actions/checkout@master
+  - uses: actions/checkout@v3
-- uses: actions/setup-go@v1
+  - uses: actions/setup-go@v3
-  with:
+    with:
-    go-version: '1.9.3' # The Go version to download (if necessary) and use.
+      go-version: '1.16.1' # The Go version to download (if necessary) and use.
-- run: go run hello.go
+  - run: go run hello.go
 ```
 
-Matrix Testing:
+
+## Check latest version
+
+The `check-latest` flag defaults to `false`. Use the default or set `check-latest` to `false` if you prefer stability and if you want to ensure a specific Go version is always used.
+
+If `check-latest` is set to `true`, the action first checks if the cached version is the latest one. If the locally cached version is not the most up-to-date, a Go version will then be downloaded. Set `check-latest` to `true` if you want the most up-to-date Go version to always be used.
+
+> Setting `check-latest` to `true` has performance implications as downloading Go versions is slower than using cached versions.
+
+```yaml
+steps:
+  - uses: actions/checkout@v3
+  - uses: actions/setup-go@v3
+    with:
+      go-version: '1.14'
+      check-latest: true
+  - run: go run hello.go
+```
+## Caching dependency files and build outputs:
+
+The action has a built-in functionality for caching and restoring go modules and build outputs. It uses [actions/cache](https://github.com/actions/cache) under the hood but requires less configuration settings. The `cache` input is optional, and caching is turned off by default.
+
+The action defaults to search for the dependency file - go.sum in the repository root, and uses its hash as a part of the cache key. Use `cache-dependency-path` input for cases when multiple dependency files are used, or they are located in different subdirectories.
+
+**Caching without specifying dependency file path**
+```yaml
+steps:
+  - uses: actions/checkout@v3
+  - uses: actions/setup-go@v3
+    with:
+      go-version: '1.17'
+      check-latest: true
+      cache: true
+  - run: go run hello.go
+```
+
+**Caching in monorepos**
+```yaml
+steps:
+  - uses: actions/checkout@v3
+  - uses: actions/setup-go@v3
+    with:
+      go-version: '1.17'
+      check-latest: true
+      cache: true
+      cache-dependency-path: subdir/go.sum
+  - run: go run hello.go
+  ```
+## Getting go version from the go.mod file
+
+The `go-version-file` input accepts a path to a `go.mod` file containing the version of Go to be used by a project. As the `go.mod` file contains only major and minor (e.g. 1.18) tags, the action will search for the latest available patch version sequentially in the runner's directory with the cached tools, in the [version-manifest.json](https://github.com/actions/go-versions/blob/main/versions-manifest.json) file or at the go servers.
+
+If both the `go-version` and the `go-version-file` inputs are provided then the `go-version` input is used.
+> The action will search for the `go.mod` file relative to the repository root
+
+```yaml
+steps:
+- uses: actions/checkout@v3
+- uses: actions/setup-go@v3
+  with:
+    go-version-file: 'path/to/go.mod'
+- run: go version
+```
+
+## Matrix testing
+
 ```yaml
 jobs:
   build:
-    runs-on: ubuntu-16.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
-        go: [ '1.13', '1.12' ]
+        go: [ '1.14', '1.13' ]
     name: Go ${{ matrix.go }} sample
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - name: Setup go
-        uses: actions/setup-go@v1
+        uses: actions/setup-go@v3
         with:
           go-version: ${{ matrix.go }}
       - run: go run hello.go
 ```
 
+### Supported version syntax
+
+The `go-version` input supports the following syntax:
+
+- Specific versions: `1.15`, `1.16.1`, `1.17.0-rc.2`, `1.16.0-beta.1`
+- SemVer's version range syntax: `^1.13.1`, `>=1.18.0-rc.1`
+
+For more information about semantic versioning, please refer to [semver](https://github.com/npm/node-semver) documentation.
+
 # License
 
 The scripts and documentation in this project are released under the [MIT License](LICENSE)
 
 # Contributions
 
-Contributions are welcome!  See [Contributor's Guide](docs/contributors.md)
+Contributions are welcome! See [Contributor's Guide](docs/contributors.md)
 
 ## Code of Conduct
 
-:wave: Be nice.  See [our code of conduct](CONDUCT)
+:wave: Be nice. See [our code of conduct](CONDUCT)

__tests__/cache-restore.test.ts

@@ -0,0 +1,86 @@
+import * as cache from '@actions/cache';
+import * as core from '@actions/core';
+import * as glob from '@actions/glob';
+
+import * as cacheRestore from '../src/cache-restore';
+import * as cacheUtils from '../src/cache-utils';
+import {PackageManagerInfo} from '../src/package-managers';
+
+describe('restoreCache', () => {
+  //Arrange
+  let hashFilesSpy = jest.spyOn(glob, 'hashFiles');
+  let getCacheDirectoryPathSpy = jest.spyOn(
+    cacheUtils,
+    'getCacheDirectoryPath'
+  );
+  let restoreCacheSpy = jest.spyOn(cache, 'restoreCache');
+  let infoSpy = jest.spyOn(core, 'info');
+  let setOutputSpy = jest.spyOn(core, 'setOutput');
+
+  const packageManager = 'default';
+  const cacheDependencyPath = 'path';
+
+  beforeEach(() => {
+    getCacheDirectoryPathSpy.mockImplementation(
+      (PackageManager: PackageManagerInfo) => {
+        return new Promise<string[]>(resolve => {
+          resolve(['cache_directory_path', 'cache_directory_path']);
+        });
+      }
+    );
+  });
+
+  it('should throw if dependency file path is not valid', async () => {
+    //Arrange
+    hashFilesSpy.mockImplementation((somePath: string) => {
+      return new Promise<string>(resolve => {
+        resolve('');
+      });
+    });
+
+    //Act + Assert
+    expect(async () => {
+      await cacheRestore.restoreCache(packageManager, cacheDependencyPath);
+    }).rejects.toThrowError(
+      'Some specified paths were not resolved, unable to cache dependencies.'
+    );
+  });
+
+  it('should inform if cache hit is not occured', async () => {
+    //Arrange
+    hashFilesSpy.mockImplementation((somePath: string) => {
+      return new Promise<string>(resolve => {
+        resolve('file_hash');
+      });
+    });
+
+    restoreCacheSpy.mockImplementation(() => {
+      return new Promise<string>(resolve => {
+        resolve('');
+      });
+    });
+
+    //Act + Assert
+    await cacheRestore.restoreCache(packageManager, cacheDependencyPath);
+    expect(infoSpy).toBeCalledWith(`Cache is not found`);
+  });
+
+  it('should set output if cache hit is occured', async () => {
+    //Arrange
+    hashFilesSpy.mockImplementation((somePath: string) => {
+      return new Promise<string>(resolve => {
+        resolve('file_hash');
+      });
+    });
+
+    restoreCacheSpy.mockImplementation(() => {
+      return new Promise<string>(resolve => {
+        resolve('cache_key');
+      });
+    });
+
+    //Act + Assert
+    await cacheRestore.restoreCache(packageManager, cacheDependencyPath);
+    expect(setOutputSpy).toBeCalledWith('cache-hit', true);
+  });
+});

__tests__/cache-utils.test.ts

@@ -0,0 +1,179 @@
+import * as exec from '@actions/exec';
+import * as cache from '@actions/cache';
+import * as core from '@actions/core';
+import * as cacheUtils from '../src/cache-utils';
+import {PackageManagerInfo} from '../src/package-managers';
+
+describe('getCommandOutput', () => {
+  //Arrange
+  let getExecOutputSpy = jest.spyOn(exec, 'getExecOutput');
+
+  it('should return trimmed stdout in case of successful exit code', async () => {
+    //Arrange
+    const stdoutResult = ' stdout ';
+    const trimmedStdout = stdoutResult.trim();
+
+    getExecOutputSpy.mockImplementation((commandLine: string) => {
+      return new Promise<exec.ExecOutput>(resolve => {
+        resolve({exitCode: 0, stdout: stdoutResult, stderr: ''});
+      });
+    });
+
+    //Act + Assert
+    return cacheUtils
+      .getCommandOutput('command')
+      .then(data => expect(data).toBe(trimmedStdout));
+  });
+
+  it('should return error in case of unsuccessful exit code', async () => {
+    //Arrange
+    const stderrResult = 'error message';
+
+    getExecOutputSpy.mockImplementation((commandLine: string) => {
+      return new Promise<exec.ExecOutput>(resolve => {
+        resolve({exitCode: 10, stdout: '', stderr: stderrResult});
+      });
+    });
+
+    //Act + Assert
+    expect(async () => {
+      await cacheUtils.getCommandOutput('command');
+    }).rejects.toThrow();
+  });
+});
+
+describe('getPackageManagerInfo', () => {
+  it('should return package manager info in case of valid package manager name', async () => {
+    //Arrange
+    const packageManagerName = 'default';
+    const expectedResult = {
+      dependencyFilePattern: 'go.sum',
+      cacheFolderCommandList: ['go env GOMODCACHE', 'go env GOCACHE']
+    };
+
+    //Act + Assert
+    return cacheUtils
+      .getPackageManagerInfo(packageManagerName)
+      .then(data => expect(data).toEqual(expectedResult));
+  });
+
+  it('should throw the error in case of invalid package manager name', async () => {
+    //Arrange
+    const packageManagerName = 'invalidName';
+
+    //Act + Assert
+    expect(async () => {
+      await cacheUtils.getPackageManagerInfo(packageManagerName);
+    }).rejects.toThrow();
+  });
+});
+
+describe('getCacheDirectoryPath', () => {
+  //Arrange
+  let getExecOutputSpy = jest.spyOn(exec, 'getExecOutput');
+
+  const validPackageManager: PackageManagerInfo = {
+    dependencyFilePattern: 'go.sum',
+    cacheFolderCommandList: ['go env GOMODCACHE', 'go env GOCACHE']
+  };
+
+  it('should return path to the cache folders which specified package manager uses', async () => {
+    //Arrange
+    getExecOutputSpy.mockImplementation((commandLine: string) => {
+      return new Promise<exec.ExecOutput>(resolve => {
+        resolve({exitCode: 0, stdout: 'path/to/cache/folder', stderr: ''});
+      });
+    });
+
+    const expectedResult = ['path/to/cache/folder', 'path/to/cache/folder'];
+
+    //Act + Assert
+    return cacheUtils
+      .getCacheDirectoryPath(validPackageManager)
+      .then(data => expect(data).toEqual(expectedResult));
+  });
+
+  it('should throw if the specified package name is invalid', async () => {
+    getExecOutputSpy.mockImplementation((commandLine: string) => {
+      return new Promise<exec.ExecOutput>(resolve => {
+        resolve({exitCode: 10, stdout: '', stderr: 'Error message'});
+      });
+    });
+
+    //Act + Assert
+    expect(async () => {
+      await cacheUtils.getCacheDirectoryPath(validPackageManager);
+    }).rejects.toThrow();
+  });
+});
+
+describe('isCacheFeatureAvailable', () => {
+  //Arrange
+  let isFeatureAvailableSpy = jest.spyOn(cache, 'isFeatureAvailable');
+  let warningSpy = jest.spyOn(core, 'warning');
+
+  it('should return true when cache feature is available', () => {
+    //Arrange
+    isFeatureAvailableSpy.mockImplementation(() => {
+      return true;
+    });
+
+    let functionResult;
+
+    //Act
+    functionResult = cacheUtils.isCacheFeatureAvailable();
+
+    //Assert
+    expect(functionResult).toBeTruthy();
+  });
+
+  it('should warn when cache feature is unavailable and GHES is not used ', () => {
+    //Arrange
+    isFeatureAvailableSpy.mockImplementation(() => {
+      return false;
+    });
+
+    process.env['GITHUB_SERVER_URL'] = 'https://github.com';
+
+    let warningMessage =
+      'The runner was not able to contact the cache service. Caching will be skipped';
+
+    //Act
+    cacheUtils.isCacheFeatureAvailable();
+
+    //Assert
+    expect(warningSpy).toHaveBeenCalledWith(warningMessage);
+  });
+
+  it('should return false when cache feature is unavailable', () => {
+    //Arrange
+    isFeatureAvailableSpy.mockImplementation(() => {
+      return false;
+    });
+
+    process.env['GITHUB_SERVER_URL'] = 'https://github.com';
+
+    let functionResult;
+
+    //Act
+    functionResult = cacheUtils.isCacheFeatureAvailable();
+
+    //Assert
+    expect(functionResult).toBeFalsy();
+  });
+
+  it('should throw when cache feature is unavailable and GHES is used', () => {
+    //Arrange
+    isFeatureAvailableSpy.mockImplementation(() => {
+      return false;
+    });
+
+    process.env['GITHUB_SERVER_URL'] = 'https://nongithub.com';
+
+    let errorMessage =
+      'Cache action is only supported on GHES version >= 3.5. If you are on version >=3.5 Please check with GHES admin if Actions cache service is enabled or not.';
+
+    //Act + Assert
+    expect(() => cacheUtils.isCacheFeatureAvailable()).toThrow(errorMessage);
+  });
+});

__tests__/data/go.mod

@@ -0,0 +1,12 @@
+module example.com/mymodule
+
+go 1.14
+
+require (
+	example.com/othermodule v1.2.3
+	example.com/thismodule v1.2.3
+	example.com/thatmodule v1.2.3
+)
+
+replace example.com/thatmodule => ../thatmodule
+exclude example.com/thismodule v1.3.0

__tests__/data/versions-manifest.json

@@ -0,0 +1,102 @@
+[
+    {
+      "version": "1.17.6",
+      "stable": true,
+      "release_url": "https://github.com/actions/go-versions/releases/tag/1.17.6-1668090892",
+      "files": [
+        {
+          "filename": "go-1.17.6-darwin-x64.tar.gz",
+          "arch": "x64",
+          "platform": "darwin",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.17.6-1668090892/go-1.17.6-darwin-x64.tar.gz"
+        },
+        {
+          "filename": "go-1.17.6-linux-x64.tar.gz",
+          "arch": "x64",
+          "platform": "linux",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.17.6-1668090892/go-1.17.6-linux-x64.tar.gz"
+        },
+        {
+          "filename": "go-1.17.6-win32-x64.zip",
+          "arch": "x64",
+          "platform": "win32",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.17.6-1668090892/go-1.17.6-win32-x64.zip"
+        }
+      ]
+    },
+    {
+      "version": "1.12.17",
+      "stable": true,
+      "release_url": "https://github.com/actions/go-versions/releases/tag/1.12.17-20200616.21",
+      "files": [
+        {
+          "filename": "go-1.12.17-darwin-x64.tar.gz",
+          "arch": "x64",
+          "platform": "darwin",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.12.17-20200616.21/go-1.12.17-darwin-x64.tar.gz"
+        },
+        {
+          "filename": "go-1.12.17-linux-x64.tar.gz",
+          "arch": "x64",
+          "platform": "linux",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.12.17-20200616.21/go-1.12.17-linux-x64.tar.gz"
+        },
+        {
+          "filename": "go-1.12.17-win32-x64.zip",
+          "arch": "x64",
+          "platform": "win32",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.12.17-20200616.21/go-1.12.17-win32-x64.zip"
+        }
+      ]
+    },
+    {
+      "version": "1.12.16",
+      "stable": true,
+      "release_url": "https://github.com/actions/go-versions/releases/tag/1.12.16-20200616.20",
+      "files": [
+        {
+          "filename": "go-1.12.16-darwin-x64.tar.gz",
+          "arch": "x64",
+          "platform": "darwin",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.12.16-20200616.20/go-1.12.16-darwin-x64.tar.gz"
+        },
+        {
+          "filename": "go-1.12.16-linux-x64.tar.gz",
+          "arch": "x64",
+          "platform": "linux",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.12.16-20200616.20/go-1.12.16-linux-x64.tar.gz"
+        },
+        {
+          "filename": "go-1.12.16-win32-x64.zip",
+          "arch": "x64",
+          "platform": "win32",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.12.16-20200616.20/go-1.12.16-win32-x64.zip"
+        }
+      ]
+    },
+    {
+      "version": "1.9.7",
+      "stable": true,
+      "release_url": "https://github.com/actions/go-versions/releases/tag/1.9.7-20200616.1",
+      "files": [
+        {
+          "filename": "go-1.9.7-darwin-x64.tar.gz",
+          "arch": "x64",
+          "platform": "darwin",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.9.7/go-1.9.7-darwin-x64.tar.gz"
+        },
+        {
+          "filename": "go-1.9.7-linux-x64.tar.gz",
+          "arch": "x64",
+          "platform": "linux",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.9.7/go-1.9.7-linux-x64.tar.gz"
+        },
+        {
+          "filename": "go-1.9.7-win32-x64.zip",
+          "arch": "x64",
+          "platform": "win32",
+          "download_url": "https://github.com/actions/go-versions/releases/download/1.9.7/go-1.9.7-win32-x64.zip"
+        }
+      ]
+    }
+  ]

__tests__/setup-go.test.ts

@@ -3,13 +3,14 @@ import * as io from '@actions/io';
 import * as tc from '@actions/tool-cache';
 import fs from 'fs';
 import cp from 'child_process';
-import osm = require('os');
+import osm from 'os';
 import path from 'path';
 import * as main from '../src/main';
 import * as im from '../src/installer';
 
 let goJsonData = require('./data/golang-dl.json');
 let matchers = require('../matchers.json');
+let goTestManifest = require('./data/versions-manifest.json');
 let matcherPattern = matchers.problemMatcher[0].pattern[0];
 let matcherRegExp = new RegExp(matcherPattern.regexp);
 
@@ -18,6 +19,8 @@ describe('setup-go', () => {
   let os = {} as any;
 
   let inSpy: jest.SpyInstance;
+  let getBooleanInputSpy: jest.SpyInstance;
+  let exportVarSpy: jest.SpyInstance;
   let findSpy: jest.SpyInstance;
   let cnSpy: jest.SpyInstance;
   let logSpy: jest.SpyInstance;
@@ -25,19 +28,30 @@ describe('setup-go', () => {
   let platSpy: jest.SpyInstance;
   let archSpy: jest.SpyInstance;
   let dlSpy: jest.SpyInstance;
-  let exSpy: jest.SpyInstance;
+  let extractTarSpy: jest.SpyInstance;
   let cacheSpy: jest.SpyInstance;
   let dbgSpy: jest.SpyInstance;
   let whichSpy: jest.SpyInstance;
   let existsSpy: jest.SpyInstance;
+  let readFileSpy: jest.SpyInstance;
   let mkdirpSpy: jest.SpyInstance;
   let execSpy: jest.SpyInstance;
+  let getManifestSpy: jest.SpyInstance;
+
+  beforeAll(async () => {
+    process.env['GITHUB_ENV'] = ''; // Stub out Environment file functionality so we can verify it writes to standard out (toolkit is backwards compatible)
+  }, 100000);
 
   beforeEach(() => {
+    process.env['GITHUB_PATH'] = ''; // Stub out ENV file functionality so we can verify it writes to standard out
+
     // @actions/core
     inputs = {};
     inSpy = jest.spyOn(core, 'getInput');
     inSpy.mockImplementation(name => inputs[name]);
+    getBooleanInputSpy = jest.spyOn(core, 'getBooleanInput');
+    getBooleanInputSpy.mockImplementation(name => inputs[name]);
+    exportVarSpy = jest.spyOn(core, 'exportVariable');
 
     // node
     os = {};
@@ -50,27 +64,32 @@ describe('setup-go', () => {
     // @actions/tool-cache
     findSpy = jest.spyOn(tc, 'find');
     dlSpy = jest.spyOn(tc, 'downloadTool');
-    exSpy = jest.spyOn(tc, 'extractTar');
+    extractTarSpy = jest.spyOn(tc, 'extractTar');
     cacheSpy = jest.spyOn(tc, 'cacheDir');
-    getSpy = jest.spyOn(im, 'getVersions');
+    getSpy = jest.spyOn(im, 'getVersionsDist');
+    getManifestSpy = jest.spyOn(tc, 'getManifestFromRepo');
 
     // io
     whichSpy = jest.spyOn(io, 'which');
     existsSpy = jest.spyOn(fs, 'existsSync');
+    readFileSpy = jest.spyOn(fs, 'readFileSync');
     mkdirpSpy = jest.spyOn(io, 'mkdirP');
 
+    // gets
+    getManifestSpy.mockImplementation(() => <tc.IToolRelease[]>goTestManifest);
+
     // writes
     cnSpy = jest.spyOn(process.stdout, 'write');
-    logSpy = jest.spyOn(console, 'log');
+    logSpy = jest.spyOn(core, 'info');
-    dbgSpy = jest.spyOn(main, '_debug');
+    dbgSpy = jest.spyOn(core, 'debug');
-    getSpy.mockImplementation(() => <im.IGoVersion[]>goJsonData);
+    getSpy.mockImplementation(() => <im.IGoVersion[] | null>goJsonData);
     cnSpy.mockImplementation(line => {
       // uncomment to debug
       // process.stderr.write('write:' + line + '\n');
     });
     logSpy.mockImplementation(line => {
       // uncomment to debug
-      // process.stderr.write('log:' + line + '\n');
+      //process.stderr.write('log:' + line + '\n');
     });
     dbgSpy.mockImplementation(msg => {
       // uncomment to see debug output
@@ -79,34 +98,57 @@ describe('setup-go', () => {
   });
 
   afterEach(() => {
-    jest.resetAllMocks();
+    //jest.resetAllMocks();
     jest.clearAllMocks();
     //jest.restoreAllMocks();
   });
 
-  afterAll(async () => {}, 100000);
+  afterAll(async () => {
+    jest.restoreAllMocks();
+  }, 100000);
 
-  it('can query versions', async () => {
+  it('can extract the major.minor.patch version from a given Go version string', async () => {
-    let versions: im.IGoVersion[] | null = await im.getVersions(
+    const goVersionOutput = 'go version go1.16.6 darwin/amd64';
-      'https://non.existant.com/path'
+    expect(main.parseGoVersion(goVersionOutput)).toBe('1.16.6');
-    );
-    expect(versions).toBeDefined();
-    let l: number = versions ? versions.length : 0;
-    expect(l).toBe(91);
   });
 
-  it('finds stable match for exact version', async () => {
+  it('can find 1.9.7 from manifest on osx', async () => {
+    os.platform = 'darwin';
+    os.arch = 'x64';
+
+    let match = await im.getInfoFromManifest('1.9.7', true, 'mocktoken');
+    expect(match).toBeDefined();
+    expect(match!.resolvedVersion).toBe('1.9.7');
+    expect(match!.type).toBe('manifest');
+    expect(match!.downloadUrl).toBe(
+      'https://github.com/actions/go-versions/releases/download/1.9.7/go-1.9.7-darwin-x64.tar.gz'
+    );
+  });
+
+  it('can find 1.9 from manifest on linux', async () => {
+    os.platform = 'linux';
+    os.arch = 'x64';
+
+    let match = await im.getInfoFromManifest('1.9.7', true, 'mocktoken');
+    expect(match).toBeDefined();
+    expect(match!.resolvedVersion).toBe('1.9.7');
+    expect(match!.type).toBe('manifest');
+    expect(match!.downloadUrl).toBe(
+      'https://github.com/actions/go-versions/releases/download/1.9.7/go-1.9.7-linux-x64.tar.gz'
+    );
+  });
+
+  it('can find 1.9 from manifest on windows', async () => {
     os.platform = 'win32';
     os.arch = 'x64';
 
-    // get request is already mocked
+    let match = await im.getInfoFromManifest('1.9.7', true, 'mocktoken');
-    // spec: 1.13.7 => 1.13.7 (exact)
-    let match: im.IGoVersion | undefined = await im.findMatch('1.13.7', true);
     expect(match).toBeDefined();
-    let version: string = match ? match.version : '';
+    expect(match!.resolvedVersion).toBe('1.9.7');
-    expect(version).toBe('go1.13.7');
+    expect(match!.type).toBe('manifest');
-    let fileName = match ? match.files[0].filename : '';
+    expect(match!.downloadUrl).toBe(
-    expect(fileName).toBe('go1.13.7.windows-amd64.zip');
+      'https://github.com/actions/go-versions/releases/download/1.9.7/go-1.9.7-win32-x64.zip'
+    );
   });
 
   it('finds stable match for exact dot zero version', async () => {
@@ -114,7 +156,7 @@ describe('setup-go', () => {
     os.arch = 'x64';
 
     // spec: 1.13.0 => 1.13
-    let match: im.IGoVersion | undefined = await im.findMatch('1.13.0', true);
+    let match: im.IGoVersion | undefined = await im.findMatch('1.13.0');
     expect(match).toBeDefined();
     let version: string = match ? match.version : '';
     expect(version).toBe('go1.13');
@@ -127,7 +169,7 @@ describe('setup-go', () => {
     os.arch = 'x64';
 
     // spec: 1.13 => 1.13.7 (latest)
-    let match: im.IGoVersion | undefined = await im.findMatch('1.13', true);
+    let match: im.IGoVersion | undefined = await im.findMatch('1.13');
     expect(match).toBeDefined();
     let version: string = match ? match.version : '';
     expect(version).toBe('go1.13.7');
@@ -140,7 +182,7 @@ describe('setup-go', () => {
     os.arch = 'x64';
 
     // spec: ^1.13.6 => 1.13.7
-    let match: im.IGoVersion | undefined = await im.findMatch('^1.13.6', true);
+    let match: im.IGoVersion | undefined = await im.findMatch('^1.13.6');
     expect(match).toBeDefined();
     let version: string = match ? match.version : '';
     expect(version).toBe('go1.13.7');
@@ -153,7 +195,7 @@ describe('setup-go', () => {
     os.arch = 'x32';
 
     // spec: 1 => 1.13.7 (latest)
-    let match: im.IGoVersion | undefined = await im.findMatch('1', true);
+    let match: im.IGoVersion | undefined = await im.findMatch('1');
     expect(match).toBeDefined();
     let version: string = match ? match.version : '';
     expect(version).toBe('go1.13.7');
@@ -166,10 +208,7 @@ describe('setup-go', () => {
     os.arch = 'x64';
 
     // spec: 1.14, stable=false => go1.14rc1
-    let match: im.IGoVersion | undefined = await im.findMatch(
+    let match: im.IGoVersion | undefined = await im.findMatch('1.14.0-rc.1');
-      '1.14.0-rc1',
-      false
-    );
     expect(match).toBeDefined();
     let version: string = match ? match.version : '';
     expect(version).toBe('go1.14rc1');
@@ -185,7 +224,7 @@ describe('setup-go', () => {
     findSpy.mockImplementation(() => toolPath);
     await main.run();
 
-    expect(logSpy).toHaveBeenCalledWith(`Setup go stable version spec 1.13.0`);
+    expect(logSpy).toHaveBeenCalledWith(`Setup go version spec 1.13.0`);
   });
 
   it('evaluates to stable with no input', async () => {
@@ -197,7 +236,41 @@ describe('setup-go', () => {
     findSpy.mockImplementation(() => toolPath);
     await main.run();
 
-    expect(logSpy).toHaveBeenCalledWith(`Setup go stable version spec 1.13.0`);
+    expect(logSpy).toHaveBeenCalledWith(`Setup go version spec 1.13.0`);
+  });
+
+  it('does not export any variables for Go versions >=1.9', async () => {
+    inputs['go-version'] = '1.13.0';
+    inSpy.mockImplementation(name => inputs[name]);
+
+    let toolPath = path.normalize('/cache/go/1.13.0/x64');
+    findSpy.mockImplementation(() => toolPath);
+
+    let vars: {[key: string]: string} = {};
+    exportVarSpy.mockImplementation((name: string, val: string) => {
+      vars[name] = val;
+    });
+
+    await main.run();
+    expect(vars).toStrictEqual({});
+  });
+
+  it('exports GOROOT for Go versions <1.9', async () => {
+    inputs['go-version'] = '1.8';
+    inSpy.mockImplementation(name => inputs[name]);
+
+    let toolPath = path.normalize('/cache/go/1.8.0/x64');
+    findSpy.mockImplementation(() => toolPath);
+
+    let vars: {[key: string]: string} = {};
+    exportVarSpy.mockImplementation((name: string, val: string) => {
+      vars[name] = val;
+    });
+
+    await main.run();
+    expect(vars).toStrictEqual({
+      GOROOT: toolPath
+    });
   });
 
   it('finds a version of go already in the cache', async () => {
@@ -208,6 +281,7 @@ describe('setup-go', () => {
     await main.run();
 
     let expPath = path.join(toolPath, 'bin');
+    expect(logSpy).toHaveBeenCalledWith(`Found in cache @ ${toolPath}`);
   });
 
   it('finds a version in the cache and adds it to the path', async () => {
@@ -240,14 +314,14 @@ describe('setup-go', () => {
     findSpy.mockImplementation(() => '');
     dlSpy.mockImplementation(() => '/some/temp/path');
     let toolPath = path.normalize('/cache/go/1.13.0/x64');
-    exSpy.mockImplementation(() => '/some/other/temp/path');
+    extractTarSpy.mockImplementation(() => '/some/other/temp/path');
     cacheSpy.mockImplementation(() => toolPath);
     await main.run();
 
     let expPath = path.join(toolPath, 'bin');
 
     expect(dlSpy).toHaveBeenCalled();
-    expect(exSpy).toHaveBeenCalled();
+    expect(extractTarSpy).toHaveBeenCalled();
     expect(cnSpy).toHaveBeenCalledWith(`::add-path::${expPath}${osm.EOL}`);
   });
 
@@ -261,10 +335,121 @@ describe('setup-go', () => {
     await main.run();
 
     expect(cnSpy).toHaveBeenCalledWith(
-      `::error::Could not find a version that satisfied version spec: 9.99.9${osm.EOL}`
+      `::error::Unable to find Go version '9.99.9' for platform linux and architecture x64.${osm.EOL}`
     );
   });
 
+  it('downloads a version from a manifest match', async () => {
+    os.platform = 'linux';
+    os.arch = 'x64';
+
+    let versionSpec = '1.12.16';
+
+    inputs['go-version'] = versionSpec;
+    inputs['token'] = 'faketoken';
+
+    let expectedUrl =
+      'https://github.com/actions/go-versions/releases/download/1.12.16-20200616.20/go-1.12.16-linux-x64.tar.gz';
+
+    // ... but not in the local cache
+    findSpy.mockImplementation(() => '');
+
+    dlSpy.mockImplementation(async () => '/some/temp/path');
+    let toolPath = path.normalize('/cache/go/1.12.16/x64');
+    extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+    cacheSpy.mockImplementation(async () => toolPath);
+
+    await main.run();
+
+    let expPath = path.join(toolPath, 'bin');
+
+    expect(dlSpy).toHaveBeenCalled();
+    expect(extractTarSpy).toHaveBeenCalled();
+    expect(logSpy).not.toHaveBeenCalledWith(
+      'Not found in manifest.  Falling back to download directly from Go'
+    );
+    expect(logSpy).toHaveBeenCalledWith(
+      `Acquiring 1.12.16 from ${expectedUrl}`
+    );
+
+    expect(logSpy).toHaveBeenCalledWith(`Added go to the path`);
+    expect(cnSpy).toHaveBeenCalledWith(`::add-path::${expPath}${osm.EOL}`);
+  });
+
+  it('downloads a major and minor from a manifest match', async () => {
+    os.platform = 'linux';
+    os.arch = 'x64';
+
+    let versionSpec = '1.12';
+
+    inputs['go-version'] = versionSpec;
+    inputs['token'] = 'faketoken';
+
+    let expectedUrl =
+      'https://github.com/actions/go-versions/releases/download/1.12.17-20200616.21/go-1.12.17-linux-x64.tar.gz';
+
+    // ... but not in the local cache
+    findSpy.mockImplementation(() => '');
+
+    dlSpy.mockImplementation(async () => '/some/temp/path');
+    let toolPath = path.normalize('/cache/go/1.12.17/x64');
+    extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+    cacheSpy.mockImplementation(async () => toolPath);
+
+    await main.run();
+
+    let expPath = path.join(toolPath, 'bin');
+
+    expect(dlSpy).toHaveBeenCalled();
+    expect(extractTarSpy).toHaveBeenCalled();
+    expect(logSpy).not.toHaveBeenCalledWith(
+      'Not found in manifest.  Falling back to download directly from Go'
+    );
+    expect(logSpy).toHaveBeenCalledWith(
+      `Acquiring 1.12.17 from ${expectedUrl}`
+    );
+
+    expect(logSpy).toHaveBeenCalledWith(`Added go to the path`);
+    expect(cnSpy).toHaveBeenCalledWith(`::add-path::${expPath}${osm.EOL}`);
+  });
+
+  it('falls back to a version from node dist', async () => {
+    os.platform = 'linux';
+    os.arch = 'x64';
+
+    let versionSpec = '1.12.14';
+
+    inputs['go-version'] = versionSpec;
+    inputs['token'] = 'faketoken';
+
+    let expectedUrl =
+      'https://github.com/actions/go-versions/releases/download/1.12.14-20200616.18/go-1.12.14-linux-x64.tar.gz';
+
+    // ... but not in the local cache
+    findSpy.mockImplementation(() => '');
+
+    dlSpy.mockImplementation(async () => '/some/temp/path');
+    let toolPath = path.normalize('/cache/go/1.12.14/x64');
+    extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+    cacheSpy.mockImplementation(async () => toolPath);
+
+    await main.run();
+
+    let expPath = path.join(toolPath, 'bin');
+    expect(logSpy).toHaveBeenCalledWith('Setup go version spec 1.12.14');
+    expect(findSpy).toHaveBeenCalled();
+    expect(logSpy).toHaveBeenCalledWith('Attempting to download 1.12.14...');
+    expect(dlSpy).toHaveBeenCalled();
+    expect(logSpy).toHaveBeenCalledWith('matching 1.12.14...');
+    expect(extractTarSpy).toHaveBeenCalled();
+    expect(logSpy).toHaveBeenCalledWith(
+      'Not found in manifest.  Falling back to download directly from Go'
+    );
+    expect(logSpy).toHaveBeenCalledWith(`Install from dist`);
+    expect(logSpy).toHaveBeenCalledWith(`Added go to the path`);
+    expect(cnSpy).toHaveBeenCalledWith(`::add-path::${expPath}${osm.EOL}`);
+  });
+
   it('reports a failed download', async () => {
     let errMsg = 'unhandled download message';
     os.platform = 'linux';
@@ -283,22 +468,6 @@ describe('setup-go', () => {
     );
   });
 
-  it('reports empty query results', async () => {
-    let errMsg = 'unhandled download message';
-    os.platform = 'linux';
-    os.arch = 'x64';
-
-    inputs['go-version'] = '1.13.1';
-
-    findSpy.mockImplementation(() => '');
-    getSpy.mockImplementation(() => null);
-    await main.run();
-
-    expect(cnSpy).toHaveBeenCalledWith(
-      `::error::Failed to download version 1.13.1: Error: golang download url did not return results${osm.EOL}`
-    );
-  });
-
   it('does not add BIN if go is not in path', async () => {
     whichSpy.mockImplementation(async () => {
       return '';
@@ -369,6 +538,16 @@ describe('setup-go', () => {
     expect(annotation.message).toBe('undefined: fmt.Printl');
   });
 
+  it('matches on unix path down the tree', async () => {
+    let line = 'foo/main.go:13:2: undefined: fmt.Printl';
+    let annotation = testMatch(line);
+    expect(annotation).toBeDefined();
+    expect(annotation.line).toBe(13);
+    expect(annotation.column).toBe(2);
+    expect(annotation.file).toBe('foo/main.go');
+    expect(annotation.message).toBe('undefined: fmt.Printl');
+  });
+
   it('matches on rooted unix path', async () => {
     let line = '/assert.go:4:1: missing return at end of function';
     let annotation = testMatch(line);
@@ -421,11 +600,11 @@ describe('setup-go', () => {
 
   // 1.13.1 => 1.13.1
   // 1.13 => 1.13.0
-  // 1.10beta1 => 1.10.0-beta1, 1.10rc1 => 1.10.0-rc1
+  // 1.10beta1 => 1.10.0-beta.1, 1.10rc1 => 1.10.0-rc.1
-  // 1.8.5beta1 => 1.8.5-beta1, 1.8.5rc1 => 1.8.5-rc1
+  // 1.8.5beta1 => 1.8.5-beta.1, 1.8.5rc1 => 1.8.5-rc.1
   it('converts prerelease versions', async () => {
-    expect(im.makeSemver('1.10beta1')).toBe('1.10.0-beta1');
+    expect(im.makeSemver('1.10beta1')).toBe('1.10.0-beta.1');
-    expect(im.makeSemver('1.10rc1')).toBe('1.10.0-rc1');
+    expect(im.makeSemver('1.10rc1')).toBe('1.10.0-rc.1');
   });
 
   it('converts dot zero versions', async () => {
@@ -435,4 +614,230 @@ describe('setup-go', () => {
   it('does not convert exact versions', async () => {
     expect(im.makeSemver('1.13.1')).toBe('1.13.1');
   });
+
+  describe('check-latest flag', () => {
+    it("use local version and don't check manifest if check-latest is not specified", async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      inputs['go-version'] = '1.16';
+      inputs['check-latest'] = false;
+
+      const toolPath = path.normalize('/cache/go/1.16.1/x64');
+      findSpy.mockReturnValue(toolPath);
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith(`Found in cache @ ${toolPath}`);
+      expect(logSpy).not.toHaveBeenCalledWith(
+        'Attempting to resolve the latest version from the manifest...'
+      );
+    });
+
+    it('check latest version and resolve it from local cache', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      inputs['go-version'] = '1.16';
+      inputs['check-latest'] = true;
+
+      const toolPath = path.normalize('/cache/go/1.16.1/x64');
+      findSpy.mockReturnValue(toolPath);
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith('Setup go version spec 1.16');
+      expect(logSpy).toHaveBeenCalledWith(`Found in cache @ ${toolPath}`);
+    });
+
+    it('check latest version and install it from manifest', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.17';
+      const patchVersion = '1.17.6';
+      inputs['go-version'] = versionSpec;
+      inputs['stable'] = 'true';
+      inputs['check-latest'] = true;
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      const toolPath = path.normalize('/cache/go/1.17.5/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+      const expectedUrl =
+        'https://github.com/actions/go-versions/releases/download/1.17.6-1668090892/go-1.17.6-darwin-x64.tar.gz';
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith(
+        `Setup go version spec ${versionSpec}`
+      );
+      expect(logSpy).toHaveBeenCalledWith(
+        'Attempting to resolve the latest version from the manifest...'
+      );
+      expect(logSpy).toHaveBeenCalledWith(`Resolved as '${patchVersion}'`);
+      expect(logSpy).toHaveBeenCalledWith(
+        `Attempting to download ${patchVersion}...`
+      );
+      expect(logSpy).toHaveBeenCalledWith('Extracting Go...');
+      expect(logSpy).toHaveBeenCalledWith('Adding to the cache ...');
+      expect(logSpy).toHaveBeenCalledWith('Added go to the path');
+      expect(logSpy).toHaveBeenCalledWith(
+        `Successfully set up Go version ${versionSpec}`
+      );
+    });
+
+    it('fallback to dist if version is not found in manifest', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      let versionSpec = '1.13';
+
+      inputs['go-version'] = versionSpec;
+      inputs['check-latest'] = true;
+      inputs['always-auth'] = false;
+      inputs['token'] = 'faketoken';
+
+      // ... but not in the local cache
+      findSpy.mockImplementation(() => '');
+
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      let toolPath = path.normalize('/cache/go/1.13.7/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      let expPath = path.join(toolPath, 'bin');
+
+      expect(dlSpy).toHaveBeenCalled();
+      expect(extractTarSpy).toHaveBeenCalled();
+      expect(logSpy).toHaveBeenCalledWith(
+        'Attempting to resolve the latest version from the manifest...'
+      );
+      expect(logSpy).toHaveBeenCalledWith(
+        `Failed to resolve version ${versionSpec} from manifest`
+      );
+      expect(logSpy).toHaveBeenCalledWith(
+        `Attempting to download ${versionSpec}...`
+      );
+      expect(cnSpy).toHaveBeenCalledWith(`::add-path::${expPath}${osm.EOL}`);
+    });
+
+    it('fallback to dist if manifest is not available', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      let versionSpec = '1.13';
+
+      process.env['GITHUB_PATH'] = '';
+
+      inputs['go-version'] = versionSpec;
+      inputs['check-latest'] = true;
+      inputs['always-auth'] = false;
+      inputs['token'] = 'faketoken';
+
+      // ... but not in the local cache
+      findSpy.mockImplementation(() => '');
+      getManifestSpy.mockImplementation(() => {
+        throw new Error('Unable to download manifest');
+      });
+
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      let toolPath = path.normalize('/cache/go/1.13.7/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      let expPath = path.join(toolPath, 'bin');
+
+      expect(logSpy).toHaveBeenCalledWith(
+        `Failed to resolve version ${versionSpec} from manifest`
+      );
+      expect(dlSpy).toHaveBeenCalled();
+      expect(extractTarSpy).toHaveBeenCalled();
+      expect(logSpy).toHaveBeenCalledWith(
+        'Attempting to resolve the latest version from the manifest...'
+      );
+      expect(logSpy).toHaveBeenCalledWith(
+        'Unable to resolve a version from the manifest...'
+      );
+      expect(logSpy).toHaveBeenCalledWith(
+        `Failed to resolve version ${versionSpec} from manifest`
+      );
+      expect(logSpy).toHaveBeenCalledWith(
+        `Attempting to download ${versionSpec}...`
+      );
+
+      expect(cnSpy).toHaveBeenCalledWith(`::add-path::${expPath}${osm.EOL}`);
+    });
+  });
+
+  describe('go-version-file', () => {
+    const goModContents = `module example.com/mymodule
+
+go 1.14
+
+require (
+	example.com/othermodule v1.2.3
+	example.com/thismodule v1.2.3
+	example.com/thatmodule v1.2.3
+)
+
+replace example.com/thatmodule => ../thatmodule
+exclude example.com/thismodule v1.3.0
+`;
+
+    it('reads version from go.mod', async () => {
+      inputs['go-version-file'] = 'go.mod';
+      existsSpy.mockImplementation(path => true);
+      readFileSpy.mockImplementation(() => Buffer.from(goModContents));
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith('Setup go version spec 1.14');
+      expect(logSpy).toHaveBeenCalledWith('Attempting to download 1.14...');
+      expect(logSpy).toHaveBeenCalledWith('matching 1.14...');
+    });
+
+    it('reads version from .go-version', async () => {
+      inputs['go-version-file'] = '.go-version';
+      existsSpy.mockImplementation(path => true);
+      readFileSpy.mockImplementation(() => Buffer.from(`1.13.0${osm.EOL}`));
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith('Setup go version spec 1.13.0');
+      expect(logSpy).toHaveBeenCalledWith('Attempting to download 1.13.0...');
+      expect(logSpy).toHaveBeenCalledWith('matching 1.13.0...');
+    });
+
+    it('is overwritten by go-version', async () => {
+      inputs['go-version'] = '1.13.1';
+      inputs['go-version-file'] = 'go.mod';
+      existsSpy.mockImplementation(path => true);
+      readFileSpy.mockImplementation(() => Buffer.from(goModContents));
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith('Setup go version spec 1.13.1');
+      expect(logSpy).toHaveBeenCalledWith('Attempting to download 1.13.1...');
+      expect(logSpy).toHaveBeenCalledWith('matching 1.13.1...');
+    });
+
+    it('reports a read failure', async () => {
+      inputs['go-version-file'] = 'go.mod';
+      existsSpy.mockImplementation(path => false);
+
+      await main.run();
+
+      expect(cnSpy).toHaveBeenCalledWith(
+        `::error::The specified go version file at: go.mod does not exist${osm.EOL}`
+      );
+    });
+  });
 });

__tests__/verify-go.sh

@@ -0,0 +1,14 @@
+  
+#!/bin/sh
+
+if [ -z "$1" ]; then
+  echo "Must supply go version argument"
+  exit 1
+fi
+
+go_version="$(go version)"
+echo "Found go version '$go_version'"
+if [ -z "$(echo $go_version | grep $1)" ]; then
+  echo "Unexpected version"
+  exit 1
+fi

action.yml

@@ -4,9 +4,26 @@ author: 'GitHub'
 inputs:
   go-version:
     description: 'The Go version to download (if necessary) and use. Supports semver spec and ranges.'
-  stable:
+  go-version-file:
-    description: 'Whether to download only stable versions'
+    description: 'Path to the go.mod file.'
-    default: 'true'
+  check-latest:
+    description: 'Set this option to true if you want the action to always check for the latest available version that satisfies the version spec'
+    default: false
+  token:
+    description: Used to pull node distributions from go-versions.  Since there's a default, this is typically not supplied by the user.
+    default: ${{ github.token }}
+  cache:
+    description: Used to specify whether caching is needed. Set to true, if you'd like to enable caching.
+    default: false
+  cache-dependency-path:
+    description: 'Used to specify the path to a dependency file - go.sum'
+outputs:
+  go-version:
+    description: 'The installed Go version. Useful when given a version range as input.'  
+  cache-hit: 
+    description: 'A boolean value to indicate if a cache was hit'
 runs:
-  using: 'node12'
+  using: 'node16'
-  main: 'dist/index.js'
+  main: 'dist/setup/index.js'
+  post: 'dist/cache-save/index.js'
+  post-if: success()

docs/adrs/0000-caching-dependencies.md

@@ -0,0 +1,69 @@
+# 0. Caching dependencies
+Date: 2022-04-13
+
+Status: Accepted
+
+# Context
+`actions/setup-go` is the one of the most popular action related to Golang in GitHub Actions. Many customers use it in conjunction with [actions/cache](https://github.com/actions/cache) to speed up dependency installation process.  
+See more examples on proper usage in [actions/cache documentation](https://github.com/actions/cache/blob/main/examples.md#go---modules).
+
+# Goals & Anti-Goals
+Integration of caching functionality into `actions/setup-go` action will bring the following benefits for action users:
+- Decrease the entry threshold for using the cache for Go dependencies and simplify initial configuration
+- Simplify YAML pipelines because there will be no need for additional steps to enable caching
+- More users will use cache for Go so more customers will have fast builds!
+
+We don't pursue the goal to provide wide customization of caching in scope of `actions/setup-go` action. The purpose of this integration is covering ~90% of basic use-cases. If user needs flexible customization, we should advice them to use `actions/cache` directly.
+
+# Decision
+- Add `cache` input parameter to `actions/setup-go`. For now, input will accept the following values: 
+  - `true` - enable caching for go dependencies
+  - `false`- disable caching for go dependencies. This value will be set as default value
+- Cache feature will be disabled by default to make sure that we don't break existing customers. We will consider enabling cache by default in next major releases
+- Action will try to search a go.sum files in the repository and throw error in the scenario that it was not found
+- The hash of found file will be used as cache key (the same approach like [actions/cache](https://github.com/actions/cache/blob/main/examples.md#go---modules) recommends)
+- The following key cache will be used `${{ runner.os }}-go${{ go-version }}-${{ hashFiles('<go.sum-path>') }}`
+- Action will cache global cache from the `go env GOMODCACHE` and `go env GOCACHE` commands.
+- Add a `cache-dependency-path` input parameter to `actions/setup-go`. The new input will accept an array or regex of dependency files. The field will accept a path (relative to the repository root) to dependency files. If the provided path contains wildcards, the action will search all matching files and calculate a common hash like the ${{ hashFiles('**/go.sum') }} YAML construction does.
+
+# Example of real use-cases
+
+ - With cache
+
+```yml
+steps:
+- uses: actions/checkout@v3
+- uses: actions/setup-go@v3
+  with:
+    go-version: '18'
+    cache: true
+```
+
+ - With cache-dependency-path
+
+ ```yml
+steps:
+- uses: actions/checkout@v3
+- uses: actions/setup-go@v3
+  with:
+    go-version: '18'
+    cache: true
+    cache-dependency-path: **/go.sum
+```
+
+ ```yml
+steps:
+- uses: actions/checkout@v3
+- uses: actions/setup-go@v3
+  with:
+    go-version: '18'
+    cache: true
+    cache-dependency-path: |
+        **/go.sum
+        **/go.mod
+```
+
+# Release process
+
+As soon as functionality is implemented, we will release minor update of action. No need to bump major version since there are no breaking changes for existing users.
+After that, we will update [starter-workflows](https://github.com/actions/starter-workflows/blob/main/ci/go.yml)

matchers.json

@@ -4,7 +4,7 @@
             "owner": "go",
             "pattern": [
                 {
-                    "regexp": "^\\s*(\\.{0,2}[\\/\\\\].+\\.go):(?:(\\d+):(\\d+):)? (.*)",
+                    "regexp": "^\\s*(.+\\.go):(?:(\\d+):(\\d+):)? (.*)",
                     "file": 1,
                     "line": 2,
                     "column": 3,

package.json

@@ -5,7 +5,7 @@
   "description": "setup go action",
   "main": "lib/setup-go.js",
   "scripts": {
-    "build": "tsc && ncc build",
+    "build": "tsc && ncc build -o dist/setup src/setup-go.ts && ncc build -o dist/cache-save src/cache-save.ts",
     "format": "prettier --write **/*.ts",
     "format-check": "prettier --check **/*.ts",
     "test": "jest --coverage",
@@ -23,22 +23,25 @@
   "author": "GitHub",
   "license": "MIT",
   "dependencies": {
-    "@actions/core": "^1.2.2",
+    "@actions/cache": "^2.0.2",
+    "@actions/core": "^1.6.0",
+    "@actions/exec": "^1.1.0",
+    "@actions/glob": "^0.2.0",
     "@actions/http-client": "^1.0.6",
     "@actions/io": "^1.0.2",
-    "@actions/tool-cache": "^1.3.3",
+    "@actions/tool-cache": "^1.5.5",
     "semver": "^6.1.1"
   },
   "devDependencies": {
-    "@types/jest": "^24.0.13",
+    "@types/jest": "^27.0.2",
-    "@types/node": "^12.0.4",
+    "@types/node": "^16.11.25",
     "@types/semver": "^6.0.0",
-    "@zeit/ncc": "^0.21.0",
+    "@vercel/ncc": "^0.33.4",
-    "jest": "^25.2.1",
+    "jest": "^27.2.5",
-    "jest-circus": "^24.7.1",
+    "jest-circus": "^27.2.5",
     "nock": "^10.0.6",
     "prettier": "^1.17.1",
-    "ts-jest": "^24.0.2",
+    "ts-jest": "^27.0.5",
-    "typescript": "^3.5.1"
+    "typescript": "^3.8.3"
   }
 }

src/cache-restore.ts

@@ -0,0 +1,62 @@
+import * as cache from '@actions/cache';
+import * as core from '@actions/core';
+import * as glob from '@actions/glob';
+import path from 'path';
+import fs from 'fs';
+
+import {State, Outputs} from './constants';
+import {PackageManagerInfo} from './package-managers';
+import {getCacheDirectoryPath, getPackageManagerInfo} from './cache-utils';
+
+export const restoreCache = async (
+  packageManager: string,
+  cacheDependencyPath?: string
+) => {
+  const packageManagerInfo = await getPackageManagerInfo(packageManager);
+  const platform = process.env.RUNNER_OS;
+  const versionSpec = core.getInput('go-version');
+
+  const cachePaths = await getCacheDirectoryPath(packageManagerInfo);
+
+  const dependencyFilePath = cacheDependencyPath
+    ? cacheDependencyPath
+    : findDependencyFile(packageManagerInfo);
+  const fileHash = await glob.hashFiles(dependencyFilePath);
+
+  if (!fileHash) {
+    throw new Error(
+      'Some specified paths were not resolved, unable to cache dependencies.'
+    );
+  }
+
+  const primaryKey = `setup-go-${platform}-go-${versionSpec}-${fileHash}`;
+  core.debug(`primary key is ${primaryKey}`);
+
+  core.saveState(State.CachePrimaryKey, primaryKey);
+
+  const cacheKey = await cache.restoreCache(cachePaths, primaryKey);
+  core.setOutput(Outputs.CacheHit, Boolean(cacheKey));
+
+  if (!cacheKey) {
+    core.info(`Cache is not found`);
+    return;
+  }
+
+  core.saveState(State.CacheMatchedKey, cacheKey);
+  core.info(`Cache restored from key: ${cacheKey}`);
+};
+
+const findDependencyFile = (packageManager: PackageManagerInfo) => {
+  let dependencyFile = packageManager.dependencyFilePattern;
+  const workspace = process.env.GITHUB_WORKSPACE!;
+  const rootContent = fs.readdirSync(workspace);
+
+  const goSumFileExists = rootContent.includes(dependencyFile);
+  if (!goSumFileExists) {
+    throw new Error(
+      `Dependencies file is not found in ${workspace}. Supported file pattern: ${dependencyFile}`
+    );
+  }
+
+  return path.join(workspace, dependencyFile);
+};

src/cache-save.ts

@@ -0,0 +1,80 @@
+import * as core from '@actions/core';
+import * as cache from '@actions/cache';
+import fs from 'fs';
+import {State} from './constants';
+import {getCacheDirectoryPath, getPackageManagerInfo} from './cache-utils';
+
+// Catch and log any unhandled exceptions.  These exceptions can leak out of the uploadChunk method in
+// @actions/toolkit when a failed upload closes the file descriptor causing any in-process reads to
+// throw an uncaught exception.  Instead of failing this action, just warn.
+process.on('uncaughtException', e => {
+  const warningPrefix = '[warning]';
+  core.info(`${warningPrefix}${e.message}`);
+});
+
+export async function run() {
+  try {
+    await cachePackages();
+  } catch (error) {
+    core.setFailed(error.message);
+  }
+}
+
+const cachePackages = async () => {
+  const cacheInput = core.getBooleanInput('cache');
+  if (!cacheInput) {
+    return;
+  }
+
+  const packageManager = 'default';
+
+  const state = core.getState(State.CacheMatchedKey);
+  const primaryKey = core.getState(State.CachePrimaryKey);
+
+  const packageManagerInfo = await getPackageManagerInfo(packageManager);
+
+  const cachePaths = await getCacheDirectoryPath(packageManagerInfo);
+
+  const nonExistingPaths = cachePaths.filter(
+    cachePath => !fs.existsSync(cachePath)
+  );
+
+  if (nonExistingPaths.length === cachePaths.length) {
+    throw new Error(`There are no cache folders on the disk`);
+  }
+
+  if (nonExistingPaths.length) {
+    logWarning(
+      `Cache folder path is retrieved but doesn't exist on disk: ${nonExistingPaths.join(
+        ', '
+      )}`
+    );
+  }
+
+  if (primaryKey === state) {
+    core.info(
+      `Cache hit occurred on the primary key ${primaryKey}, not saving cache.`
+    );
+    return;
+  }
+
+  try {
+    await cache.saveCache(cachePaths, primaryKey);
+    core.info(`Cache saved with the key: ${primaryKey}`);
+  } catch (error) {
+    if (error.name === cache.ValidationError.name) {
+      throw error;
+    } else if (error.name === cache.ReserveCacheError.name) {
+      core.info(error.message);
+    } else {
+      core.warning(`${error.message}`);
+    }
+  }
+};
+
+export function logWarning(message: string): void {
+  const warningPrefix = '[warning]';
+  core.info(`${warningPrefix}${message}`);
+}
+
+run();

src/cache-utils.ts

@@ -0,0 +1,75 @@
+import * as cache from '@actions/cache';
+import * as core from '@actions/core';
+import * as exec from '@actions/exec';
+import {supportedPackageManagers, PackageManagerInfo} from './package-managers';
+
+export const getCommandOutput = async (toolCommand: string) => {
+  let {stdout, stderr, exitCode} = await exec.getExecOutput(
+    toolCommand,
+    undefined,
+    {ignoreReturnCode: true}
+  );
+
+  if (exitCode) {
+    stderr = !stderr.trim()
+      ? `The '${toolCommand}' command failed with exit code: ${exitCode}`
+      : stderr;
+    throw new Error(stderr);
+  }
+
+  return stdout.trim();
+};
+
+export const getPackageManagerInfo = async (packageManager: string) => {
+  if (!supportedPackageManagers[packageManager]) {
+    throw new Error(
+      `It's not possible to use ${packageManager}, please, check correctness of the package manager name spelling.`
+    );
+  }
+  const obtainedPackageManager = supportedPackageManagers[packageManager];
+
+  return obtainedPackageManager;
+};
+
+export const getCacheDirectoryPath = async (
+  packageManagerInfo: PackageManagerInfo
+) => {
+  let pathList = await Promise.all(
+    packageManagerInfo.cacheFolderCommandList.map(command =>
+      getCommandOutput(command)
+    )
+  );
+
+  const emptyPaths = pathList.filter(item => !item);
+
+  if (emptyPaths.length) {
+    throw new Error(`Could not get cache folder paths.`);
+  }
+
+  return pathList;
+};
+
+export function isGhes(): boolean {
+  const ghUrl = new URL(
+    process.env['GITHUB_SERVER_URL'] || 'https://github.com'
+  );
+  return ghUrl.hostname.toUpperCase() !== 'GITHUB.COM';
+}
+
+export function isCacheFeatureAvailable(): boolean {
+  if (!cache.isFeatureAvailable()) {
+    if (isGhes()) {
+      throw new Error(
+        'Cache action is only supported on GHES version >= 3.5. If you are on version >=3.5 Please check with GHES admin if Actions cache service is enabled or not.'
+      );
+    } else {
+      core.warning(
+        'The runner was not able to contact the cache service. Caching will be skipped'
+      );
+    }
+
+    return false;
+  }
+
+  return true;
+}

src/constants.ts

@@ -0,0 +1,8 @@
+export enum State {
+  CachePrimaryKey = 'CACHE_KEY',
+  CacheMatchedKey = 'CACHE_RESULT'
+}
+
+export enum Outputs {
+  CacheHit = 'cache-hit'
+}

src/installer.ts

@@ -1,46 +1,13 @@
 import * as tc from '@actions/tool-cache';
+import * as core from '@actions/core';
 import * as path from 'path';
 import * as semver from 'semver';
 import * as httpm from '@actions/http-client';
 import * as sys from './system';
-import {debug} from '@actions/core';
+import fs from 'fs';
+import os from 'os';
 
-export async function downloadGo(
+type InstallationType = 'dist' | 'manifest';
-  versionSpec: string,
-  stable: boolean
-): Promise<string | undefined> {
-  let toolPath: string | undefined;
-
-  try {
-    let match: IGoVersion | undefined = await findMatch(versionSpec, stable);
-
-    if (match) {
-      // download
-      debug(`match ${match.version}`);
-      let downloadUrl: string = `https://storage.googleapis.com/golang/${match.files[0].filename}`;
-      console.log(`Downloading from ${downloadUrl}`);
-
-      let downloadPath: string = await tc.downloadTool(downloadUrl);
-      debug(`downloaded to ${downloadPath}`);
-
-      // extract
-      console.log('Extracting ...');
-      let extPath: string =
-        sys.getPlatform() == 'windows'
-          ? await tc.extractZip(downloadPath)
-          : await tc.extractTar(downloadPath);
-      debug(`extracted to ${extPath}`);
-
-      // extracts with a root folder that matches the fileName downloaded
-      const toolRoot = path.join(extPath, 'go');
-      toolPath = await tc.cacheDir(toolRoot, 'go', makeSemver(match.version));
-    }
-  } catch (error) {
-    throw new Error(`Failed to download version ${versionSpec}: ${error}`);
-  }
-
-  return toolPath;
-}
 
 export interface IGoVersionFile {
   filename: string;
@@ -55,9 +22,195 @@ export interface IGoVersion {
   files: IGoVersionFile[];
 }
 
-export async function findMatch(
+export interface IGoVersionInfo {
+  type: InstallationType;
+  downloadUrl: string;
+  resolvedVersion: string;
+  fileName: string;
+}
+
+export async function getGo(
   versionSpec: string,
-  stable: boolean
+  checkLatest: boolean,
+  auth: string | undefined
+) {
+  let osPlat: string = os.platform();
+  let osArch: string = os.arch();
+
+  if (checkLatest) {
+    core.info('Attempting to resolve the latest version from the manifest...');
+    const resolvedVersion = await resolveVersionFromManifest(
+      versionSpec,
+      true,
+      auth
+    );
+    if (resolvedVersion) {
+      versionSpec = resolvedVersion;
+      core.info(`Resolved as '${versionSpec}'`);
+    } else {
+      core.info(`Failed to resolve version ${versionSpec} from manifest`);
+    }
+  }
+
+  // check cache
+  let toolPath: string;
+  toolPath = tc.find('go', versionSpec);
+  // If not found in cache, download
+  if (toolPath) {
+    core.info(`Found in cache @ ${toolPath}`);
+    return toolPath;
+  }
+  core.info(`Attempting to download ${versionSpec}...`);
+  let downloadPath = '';
+  let info: IGoVersionInfo | null = null;
+
+  //
+  // Try download from internal distribution (popular versions only)
+  //
+  try {
+    info = await getInfoFromManifest(versionSpec, true, auth);
+    if (info) {
+      downloadPath = await installGoVersion(info, auth);
+    } else {
+      core.info(
+        'Not found in manifest.  Falling back to download directly from Go'
+      );
+    }
+  } catch (err) {
+    if (
+      err instanceof tc.HTTPError &&
+      (err.httpStatusCode === 403 || err.httpStatusCode === 429)
+    ) {
+      core.info(
+        `Received HTTP status code ${err.httpStatusCode}.  This usually indicates the rate limit has been exceeded`
+      );
+    } else {
+      core.info(err.message);
+    }
+    core.debug(err.stack);
+    core.info('Falling back to download directly from Go');
+  }
+
+  //
+  // Download from storage.googleapis.com
+  //
+  if (!downloadPath) {
+    info = await getInfoFromDist(versionSpec);
+    if (!info) {
+      throw new Error(
+        `Unable to find Go version '${versionSpec}' for platform ${osPlat} and architecture ${osArch}.`
+      );
+    }
+
+    try {
+      core.info('Install from dist');
+      downloadPath = await installGoVersion(info, undefined);
+    } catch (err) {
+      throw new Error(`Failed to download version ${versionSpec}: ${err}`);
+    }
+  }
+
+  return downloadPath;
+}
+
+async function resolveVersionFromManifest(
+  versionSpec: string,
+  stable: boolean,
+  auth: string | undefined
+): Promise<string | undefined> {
+  try {
+    const info = await getInfoFromManifest(versionSpec, stable, auth);
+    return info?.resolvedVersion;
+  } catch (err) {
+    core.info('Unable to resolve a version from the manifest...');
+    core.debug(err.message);
+  }
+}
+
+async function installGoVersion(
+  info: IGoVersionInfo,
+  auth: string | undefined
+): Promise<string> {
+  core.info(`Acquiring ${info.resolvedVersion} from ${info.downloadUrl}`);
+  const downloadPath = await tc.downloadTool(info.downloadUrl, undefined, auth);
+
+  core.info('Extracting Go...');
+  let extPath = await extractGoArchive(downloadPath);
+  core.info(`Successfully extracted go to ${extPath}`);
+  if (info.type === 'dist') {
+    extPath = path.join(extPath, 'go');
+  }
+
+  core.info('Adding to the cache ...');
+  const cachedDir = await tc.cacheDir(
+    extPath,
+    'go',
+    makeSemver(info.resolvedVersion)
+  );
+  core.info(`Successfully cached go to ${cachedDir}`);
+  return cachedDir;
+}
+
+export async function extractGoArchive(archivePath: string): Promise<string> {
+  const platform = os.platform();
+  let extPath: string;
+
+  if (platform === 'win32') {
+    extPath = await tc.extractZip(archivePath);
+  } else {
+    extPath = await tc.extractTar(archivePath);
+  }
+
+  return extPath;
+}
+
+export async function getInfoFromManifest(
+  versionSpec: string,
+  stable: boolean,
+  auth: string | undefined
+): Promise<IGoVersionInfo | null> {
+  let info: IGoVersionInfo | null = null;
+  const releases = await tc.getManifestFromRepo(
+    'actions',
+    'go-versions',
+    auth,
+    'main'
+  );
+  core.info(`matching ${versionSpec}...`);
+  const rel = await tc.findFromManifest(versionSpec, stable, releases);
+
+  if (rel && rel.files.length > 0) {
+    info = <IGoVersionInfo>{};
+    info.type = 'manifest';
+    info.resolvedVersion = rel.version;
+    info.downloadUrl = rel.files[0].download_url;
+    info.fileName = rel.files[0].filename;
+  }
+
+  return info;
+}
+
+async function getInfoFromDist(
+  versionSpec: string
+): Promise<IGoVersionInfo | null> {
+  let version: IGoVersion | undefined;
+  version = await findMatch(versionSpec);
+  if (!version) {
+    return null;
+  }
+
+  let downloadUrl: string = `https://storage.googleapis.com/golang/${version.files[0].filename}`;
+
+  return <IGoVersionInfo>{
+    type: 'dist',
+    downloadUrl: downloadUrl,
+    resolvedVersion: version.version,
+    fileName: version.files[0].filename
+  };
+}
+
+export async function findMatch(
+  versionSpec: string
 ): Promise<IGoVersion | undefined> {
   let archFilter = sys.getArch();
   let platFilter = sys.getPlatform();
@@ -66,7 +219,9 @@ export async function findMatch(
   let match: IGoVersion | undefined;
 
   const dlUrl: string = 'https://golang.org/dl/?mode=json&include=all';
-  let candidates: IGoVersion[] | null = await module.exports.getVersions(dlUrl);
+  let candidates: IGoVersion[] | null = await module.exports.getVersionsDist(
+    dlUrl
+  );
   if (!candidates) {
     throw new Error(`golang download url did not return results`);
   }
@@ -76,25 +231,17 @@ export async function findMatch(
     let candidate: IGoVersion = candidates[i];
     let version = makeSemver(candidate.version);
 
-    // 1.13.0 is advertised as 1.13 preventing being able to match exactly 1.13.0
+    core.debug(`check ${version} satisfies ${versionSpec}`);
-    // since a semver of 1.13 would match latest 1.13
+    if (semver.satisfies(version, versionSpec)) {
-    let parts: string[] = version.split('.');
-    if (parts.length == 2) {
-      version = version + '.0';
-    }
-
-    debug(`check ${version} satisfies ${versionSpec}`);
-    if (
-      semver.satisfies(version, versionSpec) &&
-      (!stable || candidate.stable === stable)
-    ) {
       goFile = candidate.files.find(file => {
-        debug(`${file.arch}===${archFilter} && ${file.os}===${platFilter}`);
+        core.debug(
+          `${file.arch}===${archFilter} && ${file.os}===${platFilter}`
+        );
         return file.arch === archFilter && file.os === platFilter;
       });
 
       if (goFile) {
-        debug(`matched ${candidate.version}`);
+        core.debug(`matched ${candidate.version}`);
         match = candidate;
         break;
       }
@@ -110,9 +257,14 @@ export async function findMatch(
   return result;
 }
 
-export async function getVersions(dlUrl: string): Promise<IGoVersion[] | null> {
+export async function getVersionsDist(
+  dlUrl: string
+): Promise<IGoVersion[] | null> {
   // this returns versions descending so latest is first
-  let http: httpm.HttpClient = new httpm.HttpClient('setup-go');
+  let http: httpm.HttpClient = new httpm.HttpClient('setup-go', [], {
+    allowRedirects: true,
+    maxRedirects: 3
+  });
   return (await http.getJson<IGoVersion[]>(dlUrl)).result;
 }
 
@@ -120,20 +272,41 @@ export async function getVersions(dlUrl: string): Promise<IGoVersion[] | null> {
 // Convert the go version syntax into semver for semver matching
 // 1.13.1 => 1.13.1
 // 1.13 => 1.13.0
-// 1.10beta1 => 1.10.0-beta1, 1.10rc1 => 1.10.0-rc1
+// 1.10beta1 => 1.10.0-beta.1, 1.10rc1 => 1.10.0-rc.1
-// 1.8.5beta1 => 1.8.5-beta1, 1.8.5rc1 => 1.8.5-rc1
+// 1.8.5beta1 => 1.8.5-beta.1, 1.8.5rc1 => 1.8.5-rc.1
 export function makeSemver(version: string): string {
   version = version.replace('go', '');
-  version = version.replace('beta', '-beta').replace('rc', '-rc');
+  version = version.replace('beta', '-beta.').replace('rc', '-rc.');
   let parts = version.split('-');
 
-  let verPart: string = parts[0];
+  let semVersion = semver.coerce(parts[0])?.version;
-  let prereleasePart = parts.length > 1 ? `-${parts[1]}` : '';
+  if (!semVersion) {
-
+    throw new Error(
-  let verParts: string[] = verPart.split('.');
+      `The version: ${version} can't be changed to SemVer notation`
-  if (verParts.length == 2) {
+    );
-    verPart += '.0';
   }
 
-  return `${verPart}${prereleasePart}`;
+  if (!parts[1]) {
+    return semVersion;
+  }
+
+  const fullVersion = semver.valid(`${semVersion}-${parts[1]}`);
+
+  if (!fullVersion) {
+    throw new Error(
+      `The version: ${version} can't be changed to SemVer notation`
+    );
+  }
+  return fullVersion;
+}
+
+export function parseGoVersionFile(versionFilePath: string): string {
+  const contents = fs.readFileSync(versionFilePath).toString();
+
+  if (path.basename(versionFilePath) === 'go.mod') {
+    const match = contents.match(/^go (\d+(\.\d+)*)/m);
+    return match ? match[1] : '';
+  }
+
+  return contents.trim();
 }

src/main.ts

@@ -1,8 +1,10 @@
 import * as core from '@actions/core';
 import * as io from '@actions/io';
-import * as tc from '@actions/tool-cache';
 import * as installer from './installer';
+import * as semver from 'semver';
 import path from 'path';
+import {restoreCache} from './cache-restore';
+import {isGhes, isCacheFeatureAvailable} from './cache-utils';
 import cp from 'child_process';
 import fs from 'fs';
 
@@ -12,50 +14,54 @@ export async function run() {
     // versionSpec is optional.  If supplied, install / use from the tool cache
     // If not supplied then problem matchers will still be setup.  Useful for self-hosted.
     //
-    let versionSpec = core.getInput('go-version');
+    const versionSpec = resolveVersionInput();
 
-    // stable will be true unless false is the exact input
+    const cache = core.getBooleanInput('cache');
-    // since getting unstable versions should be explicit
+    core.info(`Setup go version spec ${versionSpec}`);
-    let stable = (core.getInput('stable') || 'true').toUpperCase() === 'TRUE';
-
-    console.log(
-      `Setup go ${stable ? 'stable' : ''} version spec ${versionSpec}`
-    );
 
     if (versionSpec) {
-      let installDir: string | undefined = tc.find('go', versionSpec);
+      let token = core.getInput('token');
+      let auth = !token || isGhes() ? undefined : `token ${token}`;
 
-      if (!installDir) {
+      const checkLatest = core.getBooleanInput('check-latest');
-        console.log(
+      const installDir = await installer.getGo(versionSpec, checkLatest, auth);
-          `A version satisfying ${versionSpec} not found locally, attempting to download ...`
-        );
-        installDir = await installer.downloadGo(versionSpec, stable);
-        console.log('Installed');
-      }
 
-      if (installDir) {
+      core.addPath(path.join(installDir, 'bin'));
+      core.info('Added go to the path');
+
+      const version = installer.makeSemver(versionSpec);
+      // Go versions less than 1.9 require GOROOT to be set
+      if (semver.lt(version, '1.9.0')) {
+        core.info('Setting GOROOT for Go version < 1.9');
         core.exportVariable('GOROOT', installDir);
-        core.addPath(path.join(installDir, 'bin'));
-        console.log('Added go to the path');
-
-        let added = addBinToPath();
-        core.debug(`add bin ${added}`);
-      } else {
-        throw new Error(
-          `Could not find a version that satisfied version spec: ${versionSpec}`
-        );
       }
+
+      let added = await addBinToPath();
+      core.debug(`add bin ${added}`);
+      core.info(`Successfully set up Go version ${versionSpec}`);
+    }
+
+    if (cache && isCacheFeatureAvailable()) {
+      const packageManager = 'default';
+      const cacheDependencyPath = core.getInput('cache-dependency-path');
+      await restoreCache(packageManager, cacheDependencyPath);
     }
 
     // add problem matchers
-    const matchersPath = path.join(__dirname, '..', 'matchers.json');
+    const matchersPath = path.join(__dirname, '../..', 'matchers.json');
-    console.log(`##[add-matcher]${matchersPath}`);
+    core.info(`##[add-matcher]${matchersPath}`);
 
     // output the version actually being used
     let goPath = await io.which('go');
     let goVersion = (cp.execSync(`${goPath} version`) || '').toString();
+    core.info(goVersion);
 
-    console.log(goVersion);
+    core.setOutput('go-version', parseGoVersion(goVersion));
+
+    core.startGroup('go env');
+    let goEnv = (cp.execSync(`${goPath} env`) || '').toString();
+    core.info(goEnv);
+    core.endGroup();
   } catch (error) {
     core.setFailed(error.message);
   }
@@ -64,26 +70,26 @@ export async function run() {
 export async function addBinToPath(): Promise<boolean> {
   let added = false;
   let g = await io.which('go');
-  _debug(`which go :${g}:`);
+  core.debug(`which go :${g}:`);
   if (!g) {
-    _debug('go not in the path');
+    core.debug('go not in the path');
     return added;
   }
 
   let buf = cp.execSync('go env GOPATH');
-  if (buf) {
+  if (buf.length > 1) {
     let gp = buf.toString().trim();
-    _debug(`go env GOPATH :${gp}:`);
+    core.debug(`go env GOPATH :${gp}:`);
     if (!fs.existsSync(gp)) {
       // some of the hosted images have go install but not profile dir
-      _debug(`creating ${gp}`);
+      core.debug(`creating ${gp}`);
-      io.mkdirP(gp);
+      await io.mkdirP(gp);
     }
 
     let bp = path.join(gp, 'bin');
     if (!fs.existsSync(bp)) {
-      _debug(`creating ${bp}`);
+      core.debug(`creating ${bp}`);
-      io.mkdirP(bp);
+      await io.mkdirP(bp);
     }
 
     core.addPath(bp);
@@ -92,6 +98,36 @@ export async function addBinToPath(): Promise<boolean> {
   return added;
 }
 
-export function _debug(message: string) {
+export function parseGoVersion(versionString: string): string {
-  core.debug(message);
+  // get the installed version as an Action output
+  // based on go/src/cmd/go/internal/version/version.go:
+  // fmt.Printf("go version %s %s/%s\n", runtime.Version(), runtime.GOOS, runtime.GOARCH)
+  // expecting go<version> for runtime.Version()
+  return versionString.split(' ')[2].slice('go'.length);
+}
+
+function resolveVersionInput(): string {
+  let version = core.getInput('go-version');
+  const versionFilePath = core.getInput('go-version-file');
+
+  if (version && versionFilePath) {
+    core.warning(
+      'Both go-version and go-version-file inputs are specified, only go-version will be used'
+    );
+  }
+
+  if (version) {
+    return version;
+  }
+
+  if (versionFilePath) {
+    if (!fs.existsSync(versionFilePath)) {
+      throw new Error(
+        `The specified go version file at: ${versionFilePath} does not exist`
+      );
+    }
+    version = installer.parseGoVersionFile(versionFilePath);
+  }
+
+  return version;
 }

src/package-managers.ts

@@ -0,0 +1,15 @@
+type SupportedPackageManagers = {
+  [prop: string]: PackageManagerInfo;
+};
+
+export interface PackageManagerInfo {
+  dependencyFilePattern: string;
+  cacheFolderCommandList: string[];
+}
+
+export const supportedPackageManagers: SupportedPackageManagers = {
+  default: {
+    dependencyFilePattern: 'go.sum',
+    cacheFolderCommandList: ['go env GOMODCACHE', 'go env GOCACHE']
+  }
+};

src/system.ts

@@ -1,4 +1,4 @@
-let os = require('os');
+const os = require('os');
 
 export function getPlatform(): string {
   // darwin and linux match already

tsconfig.json

@@ -4,9 +4,6 @@
     // "incremental": true,                   /* Enable incremental compilation */
     "target": "es6",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
     "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
-    "lib": [
-      "es6"
-    ],
     // "allowJs": true,                       /* Allow javascript files to be compiled. */
     // "checkJs": true,                       /* Report errors in .js files. */
     // "jsx": "preserve",                     /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */
@@ -48,7 +45,8 @@
     // "typeRoots": [],                       /* List of folders to include type definitions from. */
     // "types": [],                           /* Type declaration files to be included in compilation. */
     // "allowSyntheticDefaultImports": true,  /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
-    "esModuleInterop": true                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
+    "esModuleInterop": true,                  /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
+    "sourceMap": true,
     // "preserveSymlinks": true,              /* Do not resolve the real path of symlinks. */
     // "allowUmdGlobalAccess": true,          /* Allow accessing UMD globals from modules. */