Add version-file input to read the Helm version from a .tool-versions file

README.md

@@ -13,6 +13,23 @@ Acceptable values are latest or any semantic version string like v3.5.0 Use this
   id: install
 ```
 
+Alternatively, the version can be read from a [`.tool-versions`](https://asdf-vm.com/manage/configuration.html) file (the format used by [asdf](https://asdf-vm.com/) and [mise](https://mise.jdx.dev/)) via the `version-file` input:
+
+```yaml
+- uses: azure/setup-helm@v5.0.0
+  with:
+     version-file: .tool-versions
+  id: install
+```
+
+The action reads the version declared for the `helm` tool, for example:
+
+```
+helm 3.18.4
+```
+
+If both `version` and `version-file` are set, `version` takes precedence.
+
 > [!NOTE]
 > If something goes wrong with fetching the latest version the action will use the hardcoded default version (currently v3.18.3). If you rely on a certain version higher than the default, you should explicitly use that version instead of latest.
 

action.yml

@@ -3,8 +3,11 @@ description: 'Install a specific version of helm binary. Acceptable values are l
 inputs:
    version:
       description: 'Version of helm'
-      required: true
+      required: false
       default: 'latest'
+   version-file:
+      description: 'Path to a .tool-versions file to read the helm version from'
+      required: false
    token:
       description: GitHub token. Used to be required to fetch the latest version
       required: false

src/run.test.ts

@@ -19,7 +19,8 @@ vi.mock('fs', async (importOriginal) => {
       readdirSync: vi.fn(),
       statSync: vi.fn(),
       chmodSync: vi.fn(),
-      readFileSync: vi.fn()
+      readFileSync: vi.fn(),
+      existsSync: vi.fn()
    }
 })
 
@@ -161,6 +162,53 @@ describe('run.ts', () => {
       expect(run.getValidVersion('3.8.0')).toBe('v3.8.0')
    })
 
+   test('parseToolVersions() - return the helm version from .tool-versions content', () => {
+      const content = ['nodejs 20.11.0', 'helm 3.14.0', 'terraform 1.7.0'].join(
+         '\n'
+      )
+      expect(run.parseToolVersions(content)).toBe('3.14.0')
+   })
+
+   test('parseToolVersions() - ignore comments and blank lines', () => {
+      const content = ['# tools', '', '   helm 3.15.2   ', ''].join('\n')
+      expect(run.parseToolVersions(content)).toBe('3.15.2')
+   })
+
+   test('parseToolVersions() - return the first version when several are listed', () => {
+      expect(run.parseToolVersions('helm 3.14.0 3.13.0')).toBe('3.14.0')
+   })
+
+   test('parseToolVersions() - return empty string when helm is not declared', () => {
+      expect(run.parseToolVersions('nodejs 20.11.0')).toBe('')
+   })
+
+   test('getVersionFromToolVersionsFile() - read the helm version from a file', () => {
+      vi.mocked(fs.existsSync).mockReturnValue(true)
+      vi.mocked(fs.readFileSync).mockReturnValue('helm 3.14.0')
+
+      expect(run.getVersionFromToolVersionsFile('.tool-versions')).toBe(
+         '3.14.0'
+      )
+      expect(fs.readFileSync).toHaveBeenCalledWith('.tool-versions', 'utf8')
+   })
+
+   test('getVersionFromToolVersionsFile() - throw when the file does not exist', () => {
+      vi.mocked(fs.existsSync).mockReturnValue(false)
+
+      expect(() =>
+         run.getVersionFromToolVersionsFile('missing.tool-versions')
+      ).toThrow("The version-file 'missing.tool-versions' does not exist")
+   })
+
+   test('getVersionFromToolVersionsFile() - throw when no helm version is present', () => {
+      vi.mocked(fs.existsSync).mockReturnValue(true)
+      vi.mocked(fs.readFileSync).mockReturnValue('nodejs 20.11.0')
+
+      expect(() =>
+         run.getVersionFromToolVersionsFile('.tool-versions')
+      ).toThrow("No helm version found in '.tool-versions'")
+   })
+
    test('walkSync() - return path to the all files matching fileToFind in dir', () => {
       vi.mocked(fs.readdirSync).mockImplementation((file, _?) => {
          if (file == 'mainFolder')

src/run.ts

@@ -13,7 +13,23 @@ const helmToolName = 'helm'
 export const stableHelmVersion = 'v3.18.4'
 
 export async function run() {
-   let version = core.getInput('version', {required: true})
+   let version = core.getInput('version')
+   const versionFile = core.getInput('version-file')
+
+   if (versionFile) {
+      if (version && version !== 'latest') {
+         core.warning(
+            `Both 'version' and 'version-file' inputs are specified, only 'version' will be used.`
+         )
+      } else {
+         version = getVersionFromToolVersionsFile(versionFile)
+         core.info(`Resolved Helm version '${version}' from '${versionFile}'`)
+      }
+   }
+
+   if (!version) {
+      version = 'latest'
+   }
 
    if (version !== 'latest' && version[0] !== 'v') {
       core.info('Getting latest Helm version')
@@ -46,6 +62,36 @@ export function getValidVersion(version: string): string {
    return 'v' + version
 }
 
+// Reads a .tool-versions file and returns the helm version declared in it
+export function getVersionFromToolVersionsFile(filePath: string): string {
+   if (!fs.existsSync(filePath)) {
+      throw new Error(`The version-file '${filePath}' does not exist`)
+   }
+   const content = fs.readFileSync(filePath, 'utf8')
+   const version = parseToolVersions(content)
+   if (!version) {
+      throw new Error(`No helm version found in '${filePath}'`)
+   }
+   return version
+}
+
+// Parses .tool-versions content (asdf/mise format) and returns the first
+// helm version, or an empty string when none is declared. Lines look like
+// `helm 3.14.0`; comments (#) and blank lines are ignored.
+export function parseToolVersions(content: string): string {
+   for (const line of content.split(/\r?\n/)) {
+      const trimmed = line.trim()
+      if (!trimmed || trimmed.startsWith('#')) {
+         continue
+      }
+      const [tool, version] = trimmed.split(/\s+/)
+      if (tool === helmToolName && version) {
+         return version
+      }
+   }
+   return ''
+}
+
 // Gets the latest helm version or returns a default stable if getting latest fails
 export async function getLatestHelmVersion(): Promise<string> {
    try {